50 mA, 100 mA, and 150 mA Adjustable CMOS LDOs with Shutdown

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 2010 Microchip Technology Inc.

DS21353E-page 1

TC1070/TC1071/TC1187

Features:

• 50 µA Ground Current for Longer Battery Life

• Adjustable Output Voltage

• Very Low Dropout Voltage

• Choice of 50 mA (TC1070), 100 mA (TC1071) 

and 150 mA (TC1187) Output 

• Power-Saving Shutdown mode

• Overcurrent and Overtemperature Protection

• Space-Saving 5-Pin SOT-23 Package

• Pin Compatible with Bipolar Regulators

Applications:

• Battery Operated Systems

• Portable Computers

• Medical Instruments

• Instrumentation

• Cellular/GSM/PHS Phones

• Linear Post-Regulators for SMPS

• Pagers

Typical Application

Description:

The TC1070, TC1071 and TC1187 devices are
adjustable LDOs designed to supersede a variety of
older (bipolar) voltage regulators. Total supply current
is typically 50 µA at full load (20 to 60 times lower than
in bipolar regulators).

The devices’ key features include ultra low-noise
operation, very low dropout voltage – typically 85 mV
(TC1070), 180 mV (TC1071) and 270 mV (TC1187) at
full load and fast response to step changes in load.
Supply current is reduced to 0.5 µA (maximum) when
the shutdown input is low. The devices incorporate both
overtemperature and overcurrent protection. Output
voltage is programmed with a simple resistor divider
from V

OUT

 to ADJ to GND.

The TC1070, TC1071 and TC1187 devices are stable
with an output capacitor of only 1 µF and have a
maximum output current of 50 mA, 100 mA and
150 mA, respectively. For higher output versions
please see the TC1174 (I

OUT

 = 300 mA) data sheet

(DS21363).

Package Type 

TC1070
TC1071
TC1187

V

OUT

GND

C1

1 µF  

+

V

IN

V

IN

V

OUT

1

5

2

4

3

SHDN

Shutdown Control

(from Power Control Logic)

ADJ

R1

R2

V

OUT

V

REF

R1
R2

-------

1

+

=

ADJ

SHDN

5

5-Pin SOT-23

TC1070
TC1071
TC1187

1

3

4

2

V

IN

V

OUT

GND

50 mA, 100 mA and 150 mA Adjustable CMOS LDOs with Shutdown

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TC1070/TC1071/TC1187

DS21353E-page 2

 2010 Microchip Technology Inc.

1.0

ELECTRICAL 
CHARACTERISTICS

Absolute Maximum Ratings†

Input Voltage .........................................................6.5V
Output Voltage........................... (-0.3V) to (V

IN

 + 0.3V)

Power Dissipation................Internally Limited (

Note 5

)

Maximum Voltage on Any Pin  ........ V

IN

 +0.3V to -0.3V

Operating Temperature Range...... -40°C < T

J

 < 125°C

Storage Temperature..........................-65°C to +150°C

† Notice: Stresses above those listed under "Absolute
Maximum Ratings" may cause permanent damage to
the device. These are stress ratings only and functional
operation of the device at these or any other conditions
above those indicated in the operation sections of the
specifications is not implied. Exposure to Absolute
Maximum Rating conditions for extended periods may
affect device reliability.

ELECTRICAL SPECIFICATIONS

Electrical Characteristics: V

IN

 = V

OUT

 + 1V, I

L

 = 0.1 mA, C

L

 = 3.3 µF, SHDN > V

IH

, T

A

 = +25°C, unless otherwise 

noted. Boldface type specifications apply for junction temperatures of -40°C to +125°C.

Parameter

Symbol

Min

Typ

Max

Units

Test Conditions

Input Operating Voltage

V

IN

2.7

6.0

V

Note 6

Maximum Output Current

I

OUTmax

50

mA

TC1070

100

TC1071

150

TC1187

Adjustable Output
Voltage Range

V

OUT

V

REF

5.5

V

Reference Voltage

V

REF

1.165

1.20

1.235

V

V

REF

 Temperature Coefficient

V

REF

/

T

40

ppm/°C

Note 1

Line Regulation

V

OUT

/

V

IN

0.05

0.35

%

(V

R

 + 1V) 

V

IN

6V

Load Regulation (

Note 2

)

V

OUT

/V

OUT

0.5

2

%

TC1070, TC1071
I

L

 = 0.1 mA to I

OUTmax

0.5

3

TC1187
I

L

 = 0.1 mA to I

OUTmax

Note 1:

2:

Regulation is measured at a constant junction temperature using low duty cycle pulse testing. Load regu-
lation is tested over a load range from 0.1 mA to the maximum specified output current. Changes in output 
voltage due to heating effects are covered by the thermal regulation specification.

3:

Dropout voltage is defined as the input to output differential at which the output voltage drops 2% below its 
nominal value.

4:

Thermal Regulation is defined as the change in output voltage at a time T after a change in power dissipa-
tion is applied, excluding load or line regulation effects. Specifications are for a current pulse equal to 
Ilmax at V

IN

 = 6V for T = 10 ms.

5:

The maximum allowable power dissipation is a function of ambient temperature, the maximum allowable 
junction temperature and the thermal resistance from junction-to-air (i.e., Ta, Tj, 

ja). Exceeding the maxi-

mum allowable power dissipation causes the device to initiate thermal shutdown. Please see 

Section 5.0 

“Thermal Considerations”

 for more details.

6:

The minimum VIN has to justify the conditions: V

IN

 V

R

 + V

DROPOUT

 and V

IN

 2.7V for I

L

 = 0.1 mA to 

I

OUTMAX

.

TC V

OUT

 = (V

OUTmax

 – V

OUT

MIN

) x 10

6

V

OUT

T

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 2010 Microchip Technology Inc.

DS21353E-page 3

TC1070/TC1071/TC1187

TERMPERATURE CHARACTERISTICS

Dropout Voltage (

Note 3

)

V

IN

-V

OUT

2

mV

I

L

 = 0.1 mA

65

I

L

 = 20 mA

85

120

I

L

 = 50 mA

180

250

TC1071, TC1187
I

L

 = 100 mA

270

400

TC1187
I

L

 = 150 mA

Supply Current

I

IN

50

80

µA

SHDN = V

IH

I

L

 = 0

Shutdown Supply Current

I

INSD

0.05

0.5

µA

SHDN = 

0V

Power Supply Rejection Ratio

PSRR

64

dB

F

RE

1 kHz

Output Short Circuit Current

I

OUTSC

300

450

mA

V

OUT

 = 0V

Thermal Regulation

V

OUT

/

P

D

0.04

V/W

Note 4

Thermal Shutdown 
Die Temperature

T

SD

160

°C

Thermal Shutdown Hysteresis

T

SD

10

°C

Output Noise

eN

260

nV/

Hz I

L

 = 

I

OUTmax

SHDN Input

SHDN Input High Threshold

V

IH

45

%V

IN

V

IN

 =

 2.5V to 6.5V

SHDN Input Low Threshold

V

IL

15

%V

IN

V

IN

 = 

2.5V to 6.5

V

ADJ Input

Adjust Input Leakage Current

I

ADJ

50

pA

Parameters

Sym

Min

Typ

Max

Units

Conditions

Thermal Resistance, 5L-SOT-23

JA

256

°C/W

ELECTRICAL SPECIFICATIONS (CONTINUED)

Electrical Characteristics: V

IN

 = V

OUT

 + 1V, I

L

 = 0.1 mA, C

L

 = 3.3 µF, SHDN > V

IH

, T

A

 = +25°C, unless otherwise 

noted. Boldface type specifications apply for junction temperatures of -40°C to +125°C.

Parameter

Symbol

Min

Typ

Max

Units

Test Conditions

Note 1:

2:

Regulation is measured at a constant junction temperature using low duty cycle pulse testing. Load regu-
lation is tested over a load range from 0.1 mA to the maximum specified output current. Changes in output 
voltage due to heating effects are covered by the thermal regulation specification.

3:

Dropout voltage is defined as the input to output differential at which the output voltage drops 2% below its 
nominal value.

4:

Thermal Regulation is defined as the change in output voltage at a time T after a change in power dissipa-
tion is applied, excluding load or line regulation effects. Specifications are for a current pulse equal to 
Ilmax at V

IN

 = 6V for T = 10 ms.

5:

The maximum allowable power dissipation is a function of ambient temperature, the maximum allowable 
junction temperature and the thermal resistance from junction-to-air (i.e., Ta, Tj, 

ja). Exceeding the maxi-

mum allowable power dissipation causes the device to initiate thermal shutdown. Please see 

Section 5.0 

“Thermal Considerations”

 for more details.

6:

The minimum VIN has to justify the conditions: V

IN

 V

R

 + V

DROPOUT

 and V

IN

 2.7V for I

L

 = 0.1 mA to 

I

OUTMAX

.

TC V

OUT

 = (V

OUTmax

 – V

OUT

MIN

) x 10

6

V

OUT

T

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TC1070/TC1071/TC1187

DS21353E-page 4

 2010 Microchip Technology Inc.

2.0

TYPICAL CHARACTERISTICS

Note: Unless otherwise specified, all parts are measured at temperature = +25°C.

Note:

The graphs and tables provided following this note are a statistical summary based on a limited number of
samples and are provided for informational purposes only. The performance characteristics listed herein
are not tested or guaranteed. In some graphs or tables, the data presented may be outside the specified
operating range (e.g., outside specified power supply range) and therefore outside the warranted range.

0.000

0.002

0.004

0.006

0.008

0.010

0.012

0.014

0.016

0.018

0.020

-40

-20

0

20

50

70

125

DROPOUT VOLTAGE (V)

I

LOAD

 = 10mA

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

TEMPERATURE (

°C)

Dropout Voltage vs. Temperature (V

OUT

 

= 3.3V)

0.000

0.002

0.004

0.006

0.008

0.010

0.012

0.014

0.016

0.018

0.020

-40

-20

0

20

50

70

125

DROPOUT VOLTAGE (V)

I

LOAD

 = 10mA

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

TEMPERATURE (

°C)

Dropout Voltage vs. Temperature (V

OUT

 

= 3.3V)

0

10

20

30

40

50

60

70

80

90

GND CURRENT (

μ

A)

0  0.5   1 1.5   2   2.5  3   3.5   4  4.5 5   5.5  6   6.5  7   7.5

I

LOAD

 = 10mA

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

Ground Current vs. V

IN

 (V

OUT

 

= 3.3V)

V

IN

 (V)

0.000

0.010

0.020

0.030

0.040

0.050

0.060

0.070

0.080

0.090

0.100

-40

-20

0

20

50

70

125

DROPOUT VOLTAGE (V)

I

LOAD

 = 50mA

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

TEMPERATURE (

°C)

Dropout Voltage vs. Temperature (V

OUT

 

= 3.3V)

0.000

0.050

0.100

0.150

0.200

0.250

0.300

-40

-20

0

20

50

70

125

DROPOUT VOLTAGE (V)

I

LOAD

 = 150mA

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

TEMPERATURE (

°C)

Dropout Voltage vs. Temperature (V

OUT

 

= 3.3V)

0

10

20

30

40

50

60

70

80

90

GND CURRENT (

μ

A)

0   0.5  1  1.5   2   2.5   3   3.5   4  4.5    5   5.5  6   6.5   7   7.5

I

LOAD

 = 100mA

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

Ground Current vs. V

IN

 (V

OUT

 

= 3.3V)

V

IN

 (V)

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DS21353E-page 5

TC1070/TC1071/TC1187

Note: Unless otherwise specified, all parts are measured at temperature = +25°C.

0

10

20

30

40

50

60

70

80

GND CURRENT (

μ

A)

 

0  0.5   1 1.5   2   2.5  3   3.5  4   4.5 5   5.5  6   6.5  7   7.5

I

LOAD

 = 150mA

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

V

IN

 (V)

Ground Current vs. V

IN

 (V

OUT

 

= 3.3V)

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

I

LOAD

 = 100mA

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

0    0.5   1   1.5   2   2.5   3   3.5   4   4.5   5   5.5   6   6.5   7

V

IN

 (V)

 

V

OUT

 (V)

 

V

OUT

 vs. 

V

IN

 (V

OUT

 

= 3.3V)

 

3.274

3.276

3.278

3.280

3.282

3.284

3.286

3.288

3.290

-40

-20

-10

0

20

40

85

125

I

LOAD

 = 150mA

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

V

IN

 = 4.3V

TEMPERATURE (

°C)

V

OUT

 (V)

 

Output Voltage vs. Temperature (V

OUT

 

= 3.3V)

0

0.5

1

1.5

2

2.5

3

3.5

 0    0.5   1  1.5    2   2.5   3   3.5    4   4.5   5    5.5   6   6.5   7

I

LOAD

 = 0

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

V

IN

 (V)

 

V

OUT

 (V)

 

V

OUT

 vs. 

V

IN

 (V

OUT

 

= 3.3V)

3.275

3.280

3.285

3.290

3.295

3.300

3.305

3.310

3.315

3.320

-40

-20

-10

0

20

40

85

125

I

LOAD

 = 10mA

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

V

IN

 = 4.3V

TEMPERATURE (

°C)

V

OUT

 (V)

 

Output Voltage vs. Temperature (V

OUT

 

= 3.3V)

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TC1070/TC1071/TC1187

DS21353E-page 6

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Note: Unless otherwise specified, all parts are measured at temperature = +25°C.

Note: Unless otherwise specified, all parts are measured at temperature = +25°C.

4.985

4.990

4.995

5.000

5.005

5.010

5.015

5.020

5.025

-40

-20

-10

0

20

40

85

125

I

LOAD

 = 10mA

V

IN

 

= 6V

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

TEMPERATURE (

°C)

Output Voltage vs. Temperature (V

OUT

 

= 5V)

V

OUT

 (V)

 

                                                                    

   

0

10

20

30

40

50

60

70

-40

-20

-10

0

20

40

85

125

GND CURRENT (

μ

A)

I

LOAD

 = 10mA

V

IN

 

= 6V

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

TEMPERATURE (

°C)

Temperature 

vs. Quiescent Current (V

OUT

 

= 5V)

4.974

4.976

4.978

4.980

4.982

4.984

4.986

4.988

4.990

4.992

4.994

-40

-20

-10

0

20

40

85

125

I

LOAD

 = 150mA

V

IN

 

= 6V

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

TEMPERATURE (

°C)

Output Voltage vs. Temperature (V

OUT

 

= 5V)

V

OUT

 (V)

 

Temperature vs. Quiescent Current (V

OUT

 

= 5V)

0

10

20

30

40

50

60

70

80

-40

-20

-10

0

20

40

85

125

GND CURRENT (

μ

A) 

I

LOAD

 = 150mA

V

IN

 

= 6V

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

TEMPERATURE (

°C)

10.0

1.0

0.1

0.0

0.01K 0.1K

1K

10K

100K

1000K

FREQUENCY (Hz)

Output Noise vs. Frequency

NOISE (

μ

V/

Hz)

R

LOAD

 = 50

Ω 

C

OUT 

= 1

μF

C

IN

 = 1

μF

1000

100

10

1

0.1

0.01

0

10 20 30 40 50 60 70 80 90 100

LOAD CURRENT (mA)

Stability Region vs. Load Current

C

OUT 

ESR

 

(Ω

)

C

OUT

 = 1

μ

to 10

μF

Stable Region

Stable Region

-30

-35

-40

-45

-50

-60

-55

-65

-70

-75

-80

0.01K 0.1K

1K

10K

100K 1000K

FREQUENCY (Hz)

Power Supply Rejection Ratio

PSRR (dB)

I

OUT 

=

 

10mA

V

INDC 

=

 

4V

V

INAC 

=

 

100mVp-p

V

OUT 

=

 

3V

C

IN 

=

 

0

C

OUT 

=

 

1

μF

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 2010 Microchip Technology Inc.

DS21353E-page 7

TC1070/TC1071/TC1187

V

OUT

V

SHDN

Measure Rise Time of 3.3V LDO

Conditions: C

IN

 = 1

μF, C

OUT

 = 1

μF, I

LOAD

 = 100mA, V

IN

 = 4.3V,

Temp = 25

°C, Fall Time = 184μS

V

SHDN

Measure Rise Time of 5.0V LDO

Conditions: C

IN

 = 1

μF, C

OUT

 = 1

μF, I

LOAD

 = 100mA, V

IN

 = 6V,

Temp = 25

°C, Fall Time = 192μS

V

OUT

Thermal Shutdown Response of 5.0V LDO

Conditions: V

IN

 = 6V, C

IN

 = 0

μF, C

OUT

 = 1

μF

I

LOAD

 was increased until temperature of die reached about 160

°C, at

which time integrated thermal protection circuitry shuts the regulator
off when die temperature exceeds approximately 160

°C. The regulator

remains off until die temperature drops to approximately 150

°C.

V

OUT

Measure Fall Time of 3.3V LDO

Conditions: C

IN

 = 1

μF, C

OUT

 = 1

μF, I

LOAD

 = 100mA, V

IN

 = 4.3V,

Temp = 25

°C, Fall Time = 52μS

V

OUT

V

SHDN

Measure Fall Time of 5.0V LDO

Conditions: C

IN

 = 1

μF, C

OUT

 = 1

μF, I

LOAD

 = 100mA, V

IN

 = 6V,

Temp = 25

°C, Fall Time = 88μS

V

OUT

V

SHDN

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TC1070/TC1071/TC1187

DS21353E-page 8

 2010 Microchip Technology Inc.

3.0

PIN DESCRIPTIONS

The descriptions of the pins are listed in 

Table 3-1

.

3.1

Input Voltage Supply (V

IN

)

Connect unregulated input supply to the V

IN

 pin. If

there is a large distance between the input supply and
the LDO regulator, some input capacitance is
necessary for proper operation. A 1 µF capacitor
connected from V

IN

 to ground is recommended for

most applications.

3.2

Ground (GND)

Connect the unregulated input supply ground return to
GND. Also connect the negative side of the 1 µF typical
input decoupling capacitor close to GND and the
negative side of the output capacitor C

1

 to GND.

3.3

Shutdown Control Input (SHDN)

The regulator is fully enabled when a logic high is
applied to this input. The regulator enters shutdown
when a logic low is applied to this input. During
shutdown, output voltage falls to zero and supply
current is reduced to 0.5 µA (maximum).

3.4

Output Voltage Adjust (ADJ)

Output voltage setting is programmed with a resistor
divider from V

OUT

 to this input. 

3.5

Regulated Voltage Output (V

OUT

)

Connect the output load to V

OUT

 of the LDO. Also

connect the positive side of the LDO output capacitor
as close as possible to the V

OUT

 pin.

TABLE 3-1:

PIN FUNCTION TABLE

TC1070/TC1071/TC1187

Symbol

Description

SOT-23

1

V

IN

Unregulated supply input

2

GND

Ground terminal

3

SHDN

Shutdown control input 

4

ADJ

Output voltage adjust terminal

5

V

OUT

Regulated voltage output

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 2010 Microchip Technology Inc.

DS21353E-page 9

TC1070/TC1071/TC1187

4.0

DETAILED DESCRIPTION

The TC1070, TC1071 and TC1187 are adjustable
output voltage regulators. (If a fixed version is desired,
please see the TC1014/TC1015/TC1185 data sheet –
DS21335.) Unlike bipolar regulators, the TC1070,
TC1071 and TC1187 supply current does not increase
with load current. In addition, V

OUT

 remains stable and

within regulation over the entire 0 mA to I

OUTmax

 oper-

ating load current range (an important consideration in
RTC and CMOS RAM battery back-up applications). 

Figure 4-1

 shows a typical application circuit. The

regulator is enabled any time the shutdown input
(SHDN) is at or above V

IH

, and shutdown (disabled)

when SHDN is at or below V

IL

. SHDN may be

controlled by a CMOS logic gate or I/O port of a
microcontroller. If the SHDN input is not required, it
should be connected directly to the input supply. While
in shutdown, supply current decreases to 0.05 µA
(typical) and V

OUT

 falls to zero volts.

FIGURE 4-1:

Battery-Operated Supply.

4.1

Adjust Input

The output voltage setting is determined by the values
of R

1

 and R

2

 (see 

Equation 4-1

). The ohmic values of

these resistors should be between 470K and 3M to
minimize bleeder current.

The output voltage setting is calculated using the
following equation:

EQUATION 4-1:

The voltage adjustment range of the TC1070, TC1071
and TC1187 is from V

REF

 to (V

IN

 – 0.05V).

4.2

Output Capacitor

A 1 µF (minimum) capacitor from V

OUT

 to ground is

recommended. The output capacitor should have an
effective series resistance greater than 0.1

 and less

than 5.0

, and a resonant frequency above 1 MHz.

Aluminum electrolytic or tantalum capacitor types can
be used. (Since many aluminum electrolytic capacitors
freeze at approximately -30°C, solid tantalums are rec-
ommended for applications operating below -25°C.)
When operating from sources other than batteries,
supply-noise rejection and transient response can be
improved by increasing the value of the input and
output capacitors and employing passive filtering
techniques.

4.3

Input Capacitor

A 1 µF capacitor should be connected from V

IN

 to

GND if there is more than 10 inches of wire between
the regulator and the AC filter capacitor, or if a battery
is used as power source.

TC1070
TC1071
TC1187

V

OUT

SHDN

GND

C2 +

V

IN

+2.45V

Shutdown Control

(from Power Control Logic)

C1

1 µF

+

3.0V

Battery

+

 

R1

470K

1

5

2

4

3

ADJ

R2

470K

1 µF

V

OUT

V

REF

R

1

R

2

------

1

=

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TC1070/TC1071/TC1187

DS21353E-page 10

 2010 Microchip Technology Inc.

5.0

THERMAL CONSIDERATIONS

5.1

Thermal Shutdown 

Integrated thermal protection circuitry shuts the
regulator off when die temperature exceeds 160°C.
The regulator remains off until the die temperature
drops to approximately 150°C.

5.2

Power Dissipation 

The amount of power the regulator dissipates is
primarily a function of input and output voltage, and
output current. The following equation is used to
calculate worst-case actual power dissipation:

EQUATION 5-1:

The maximum allowable power dissipation
(

Equation 5-2

) is a function of the maximum ambient

temperature (T

Amax

), the maximum allowable die

temperature (T

Jmax

) and the thermal resistance from

junction-to-air (

JA

). The 5-Pin SOT-23 package has a

JA

 of approximately 220° C/Watt.

EQUATION 5-2:

Equation 5-1

 can be used in conjunction with

Equation 5-2

 

to ensure regulator thermal operation is

within limits. For example:

Actual power dissipation:

Maximum allowable power dissipation:

In this example, the TC1070 dissipates a maximum of
26.2 mW which is below the allowable limit of 318 mW.
In a similar manner, 

Equation 5-1

 and 

Equation 5-2

 can

be used to calculate maximum current and/or input
voltage limits.

5.3

Layout Considerations

The primary path of heat conduction out of the package
is via the package leads. Therefore, layouts having a
ground plane, wide traces at the pads, and wide power
supply bus lines combine to lower 

JA

  and therefore

increase the maximum allowable power dissipation
limit.

P

D

 

 (V

INmax

 – V

OUTmin

)I

LOADmax

Where:

P

D

= Worst-case actual power dissipation

V

INmax

= Maximum voltage on V

IN

V

OUTmin

= Minimum regulator output voltage

I

LOADmax

= Maximum output (load) current

where all terms are previously defined.

P

Dmax

T

Jmax

T

Amax

J A

----------------------------------------

=

Given:

V

INmax

=

3.0V  ±10%

V

OUTmin

=

2.7V  –  2%

I

LOADmax

=

40 mA

T

Jmax

=

+125°C

T

Amax

=

+55°C

Find:

1. Actual power dissipation

2. Maximum allowable dissipation

P

D

 (V

INmax

 – V

OUTmin

)I

LOADmax

= [(3.0 x 1.10) – (2.7 x .0.98)]40 x 10

–3

= 26.2 mW

= 318 mW

125

55

220

-------------------------

=

P

Dmax

T

Jmax

T

Amax

JA

----------------------------------------

=

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 2010 Microchip Technology Inc.

DS21353E-page 1

TC1070/TC1071/TC1187

Features:

• 50 µA Ground Current for Longer Battery Life

• Adjustable Output Voltage

• Very Low Dropout Voltage

• Choice of 50 mA (TC1070), 100 mA (TC1071) 

and 150 mA (TC1187) Output 

• Power-Saving Shutdown mode

• Overcurrent and Overtemperature Protection

• Space-Saving 5-Pin SOT-23 Package

• Pin Compatible with Bipolar Regulators

Applications:

• Battery Operated Systems

• Portable Computers

• Medical Instruments

• Instrumentation

• Cellular/GSM/PHS Phones

• Linear Post-Regulators for SMPS

• Pagers

Typical Application

Description:

The TC1070, TC1071 and TC1187 devices are
adjustable LDOs designed to supersede a variety of
older (bipolar) voltage regulators. Total supply current
is typically 50 µA at full load (20 to 60 times lower than
in bipolar regulators).

The devices’ key features include ultra low-noise
operation, very low dropout voltage – typically 85 mV
(TC1070), 180 mV (TC1071) and 270 mV (TC1187) at
full load and fast response to step changes in load.
Supply current is reduced to 0.5 µA (maximum) when
the shutdown input is low. The devices incorporate both
overtemperature and overcurrent protection. Output
voltage is programmed with a simple resistor divider
from V

OUT

 to ADJ to GND.

The TC1070, TC1071 and TC1187 devices are stable
with an output capacitor of only 1 µF and have a
maximum output current of 50 mA, 100 mA and
150 mA, respectively. For higher output versions
please see the TC1174 (I

OUT

 = 300 mA) data sheet

(DS21363).

Package Type 

TC1070
TC1071
TC1187

V

OUT

GND

C1

1 µF  

+

V

IN

V

IN

V

OUT

1

5

2

4

3

SHDN

Shutdown Control

(from Power Control Logic)

ADJ

R1

R2

V

OUT

V

REF

R1
R2

-------

1

+

=

ADJ

SHDN

5

5-Pin SOT-23

TC1070
TC1071
TC1187

1

3

4

2

V

IN

V

OUT

GND

50 mA, 100 mA and 150 mA Adjustable CMOS LDOs with Shutdown

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TC1070/TC1071/TC1187

DS21353E-page 2

 2010 Microchip Technology Inc.

1.0

ELECTRICAL 
CHARACTERISTICS

Absolute Maximum Ratings†

Input Voltage .........................................................6.5V
Output Voltage........................... (-0.3V) to (V

IN

 + 0.3V)

Power Dissipation................Internally Limited (

Note 5

)

Maximum Voltage on Any Pin  ........ V

IN

 +0.3V to -0.3V

Operating Temperature Range...... -40°C < T

J

 < 125°C

Storage Temperature..........................-65°C to +150°C

† Notice: Stresses above those listed under "Absolute
Maximum Ratings" may cause permanent damage to
the device. These are stress ratings only and functional
operation of the device at these or any other conditions
above those indicated in the operation sections of the
specifications is not implied. Exposure to Absolute
Maximum Rating conditions for extended periods may
affect device reliability.

ELECTRICAL SPECIFICATIONS

Electrical Characteristics: V

IN

 = V

OUT

 + 1V, I

L

 = 0.1 mA, C

L

 = 3.3 µF, SHDN > V

IH

, T

A

 = +25°C, unless otherwise 

noted. Boldface type specifications apply for junction temperatures of -40°C to +125°C.

Parameter

Symbol

Min

Typ

Max

Units

Test Conditions

Input Operating Voltage

V

IN

2.7

6.0

V

Note 6

Maximum Output Current

I

OUTmax

50

mA

TC1070

100

TC1071

150

TC1187

Adjustable Output
Voltage Range

V

OUT

V

REF

5.5

V

Reference Voltage

V

REF

1.165

1.20

1.235

V

V

REF

 Temperature Coefficient

V

REF

/

T

40

ppm/°C

Note 1

Line Regulation

V

OUT

/

V

IN

0.05

0.35

%

(V

R

 + 1V) 

V

IN

6V

Load Regulation (

Note 2

)

V

OUT

/V

OUT

0.5

2

%

TC1070, TC1071
I

L

 = 0.1 mA to I

OUTmax

0.5

3

TC1187
I

L

 = 0.1 mA to I

OUTmax

Note 1:

2:

Regulation is measured at a constant junction temperature using low duty cycle pulse testing. Load regu-
lation is tested over a load range from 0.1 mA to the maximum specified output current. Changes in output 
voltage due to heating effects are covered by the thermal regulation specification.

3:

Dropout voltage is defined as the input to output differential at which the output voltage drops 2% below its 
nominal value.

4:

Thermal Regulation is defined as the change in output voltage at a time T after a change in power dissipa-
tion is applied, excluding load or line regulation effects. Specifications are for a current pulse equal to 
Ilmax at V

IN

 = 6V for T = 10 ms.

5:

The maximum allowable power dissipation is a function of ambient temperature, the maximum allowable 
junction temperature and the thermal resistance from junction-to-air (i.e., Ta, Tj, 

ja). Exceeding the maxi-

mum allowable power dissipation causes the device to initiate thermal shutdown. Please see 

Section 5.0 

“Thermal Considerations”

 for more details.

6:

The minimum VIN has to justify the conditions: V

IN

 V

R

 + V

DROPOUT

 and V

IN

 2.7V for I

L

 = 0.1 mA to 

I

OUTMAX

.

TC V

OUT

 = (V

OUTmax

 – V

OUT

MIN

) x 10

6

V

OUT

T

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 2010 Microchip Technology Inc.

DS21353E-page 3

TC1070/TC1071/TC1187

TERMPERATURE CHARACTERISTICS

Dropout Voltage (

Note 3

)

V

IN

-V

OUT

2

mV

I

L

 = 0.1 mA

65

I

L

 = 20 mA

85

120

I

L

 = 50 mA

180

250

TC1071, TC1187
I

L

 = 100 mA

270

400

TC1187
I

L

 = 150 mA

Supply Current

I

IN

50

80

µA

SHDN = V

IH

I

L

 = 0

Shutdown Supply Current

I

INSD

0.05

0.5

µA

SHDN = 

0V

Power Supply Rejection Ratio

PSRR

64

dB

F

RE

1 kHz

Output Short Circuit Current

I

OUTSC

300

450

mA

V

OUT

 = 0V

Thermal Regulation

V

OUT

/

P

D

0.04

V/W

Note 4

Thermal Shutdown 
Die Temperature

T

SD

160

°C

Thermal Shutdown Hysteresis

T

SD

10

°C

Output Noise

eN

260

nV/

Hz I

L

 = 

I

OUTmax

SHDN Input

SHDN Input High Threshold

V

IH

45

%V

IN

V

IN

 =

 2.5V to 6.5V

SHDN Input Low Threshold

V

IL

15

%V

IN

V

IN

 = 

2.5V to 6.5

V

ADJ Input

Adjust Input Leakage Current

I

ADJ

50

pA

Parameters

Sym

Min

Typ

Max

Units

Conditions

Thermal Resistance, 5L-SOT-23

JA

256

°C/W

ELECTRICAL SPECIFICATIONS (CONTINUED)

Electrical Characteristics: V

IN

 = V

OUT

 + 1V, I

L

 = 0.1 mA, C

L

 = 3.3 µF, SHDN > V

IH

, T

A

 = +25°C, unless otherwise 

noted. Boldface type specifications apply for junction temperatures of -40°C to +125°C.

Parameter

Symbol

Min

Typ

Max

Units

Test Conditions

Note 1:

2:

Regulation is measured at a constant junction temperature using low duty cycle pulse testing. Load regu-
lation is tested over a load range from 0.1 mA to the maximum specified output current. Changes in output 
voltage due to heating effects are covered by the thermal regulation specification.

3:

Dropout voltage is defined as the input to output differential at which the output voltage drops 2% below its 
nominal value.

4:

Thermal Regulation is defined as the change in output voltage at a time T after a change in power dissipa-
tion is applied, excluding load or line regulation effects. Specifications are for a current pulse equal to 
Ilmax at V

IN

 = 6V for T = 10 ms.

5:

The maximum allowable power dissipation is a function of ambient temperature, the maximum allowable 
junction temperature and the thermal resistance from junction-to-air (i.e., Ta, Tj, 

ja). Exceeding the maxi-

mum allowable power dissipation causes the device to initiate thermal shutdown. Please see 

Section 5.0 

“Thermal Considerations”

 for more details.

6:

The minimum VIN has to justify the conditions: V

IN

 V

R

 + V

DROPOUT

 and V

IN

 2.7V for I

L

 = 0.1 mA to 

I

OUTMAX

.

TC V

OUT

 = (V

OUTmax

 – V

OUT

MIN

) x 10

6

V

OUT

T

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TC1070/TC1071/TC1187

DS21353E-page 4

 2010 Microchip Technology Inc.

2.0

TYPICAL CHARACTERISTICS

Note: Unless otherwise specified, all parts are measured at temperature = +25°C.

Note:

The graphs and tables provided following this note are a statistical summary based on a limited number of
samples and are provided for informational purposes only. The performance characteristics listed herein
are not tested or guaranteed. In some graphs or tables, the data presented may be outside the specified
operating range (e.g., outside specified power supply range) and therefore outside the warranted range.

0.000

0.002

0.004

0.006

0.008

0.010

0.012

0.014

0.016

0.018

0.020

-40

-20

0

20

50

70

125

DROPOUT VOLTAGE (V)

I

LOAD

 = 10mA

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

TEMPERATURE (

°C)

Dropout Voltage vs. Temperature (V

OUT

 

= 3.3V)

0.000

0.002

0.004

0.006

0.008

0.010

0.012

0.014

0.016

0.018

0.020

-40

-20

0

20

50

70

125

DROPOUT VOLTAGE (V)

I

LOAD

 = 10mA

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

TEMPERATURE (

°C)

Dropout Voltage vs. Temperature (V

OUT

 

= 3.3V)

0

10

20

30

40

50

60

70

80

90

GND CURRENT (

μ

A)

0  0.5   1 1.5   2   2.5  3   3.5   4  4.5 5   5.5  6   6.5  7   7.5

I

LOAD

 = 10mA

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

Ground Current vs. V

IN

 (V

OUT

 

= 3.3V)

V

IN

 (V)

0.000

0.010

0.020

0.030

0.040

0.050

0.060

0.070

0.080

0.090

0.100

-40

-20

0

20

50

70

125

DROPOUT VOLTAGE (V)

I

LOAD

 = 50mA

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

TEMPERATURE (

°C)

Dropout Voltage vs. Temperature (V

OUT

 

= 3.3V)

0.000

0.050

0.100

0.150

0.200

0.250

0.300

-40

-20

0

20

50

70

125

DROPOUT VOLTAGE (V)

I

LOAD

 = 150mA

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

TEMPERATURE (

°C)

Dropout Voltage vs. Temperature (V

OUT

 

= 3.3V)

0

10

20

30

40

50

60

70

80

90

GND CURRENT (

μ

A)

0   0.5  1  1.5   2   2.5   3   3.5   4  4.5    5   5.5  6   6.5   7   7.5

I

LOAD

 = 100mA

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

Ground Current vs. V

IN

 (V

OUT

 

= 3.3V)

V

IN

 (V)

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 2010 Microchip Technology Inc.

DS21353E-page 5

TC1070/TC1071/TC1187

Note: Unless otherwise specified, all parts are measured at temperature = +25°C.

0

10

20

30

40

50

60

70

80

GND CURRENT (

μ

A)

 

0  0.5   1 1.5   2   2.5  3   3.5  4   4.5 5   5.5  6   6.5  7   7.5

I

LOAD

 = 150mA

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

V

IN

 (V)

Ground Current vs. V

IN

 (V

OUT

 

= 3.3V)

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

I

LOAD

 = 100mA

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

0    0.5   1   1.5   2   2.5   3   3.5   4   4.5   5   5.5   6   6.5   7

V

IN

 (V)

 

V

OUT

 (V)

 

V

OUT

 vs. 

V

IN

 (V

OUT

 

= 3.3V)

 

3.274

3.276

3.278

3.280

3.282

3.284

3.286

3.288

3.290

-40

-20

-10

0

20

40

85

125

I

LOAD

 = 150mA

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

V

IN

 = 4.3V

TEMPERATURE (

°C)

V

OUT

 (V)

 

Output Voltage vs. Temperature (V

OUT

 

= 3.3V)

0

0.5

1

1.5

2

2.5

3

3.5

 0    0.5   1  1.5    2   2.5   3   3.5    4   4.5   5    5.5   6   6.5   7

I

LOAD

 = 0

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

V

IN

 (V)

 

V

OUT

 (V)

 

V

OUT

 vs. 

V

IN

 (V

OUT

 

= 3.3V)

3.275

3.280

3.285

3.290

3.295

3.300

3.305

3.310

3.315

3.320

-40

-20

-10

0

20

40

85

125

I

LOAD

 = 10mA

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

V

IN

 = 4.3V

TEMPERATURE (

°C)

V

OUT

 (V)

 

Output Voltage vs. Temperature (V

OUT

 

= 3.3V)

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background image

TC1070/TC1071/TC1187

DS21353E-page 6

 2010 Microchip Technology Inc.

Note: Unless otherwise specified, all parts are measured at temperature = +25°C.

Note: Unless otherwise specified, all parts are measured at temperature = +25°C.

4.985

4.990

4.995

5.000

5.005

5.010

5.015

5.020

5.025

-40

-20

-10

0

20

40

85

125

I

LOAD

 = 10mA

V

IN

 

= 6V

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

TEMPERATURE (

°C)

Output Voltage vs. Temperature (V

OUT

 

= 5V)

V

OUT

 (V)

 

                                                                    

   

0

10

20

30

40

50

60

70

-40

-20

-10

0

20

40

85

125

GND CURRENT (

μ

A)

I

LOAD

 = 10mA

V

IN

 

= 6V

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

TEMPERATURE (

°C)

Temperature 

vs. Quiescent Current (V

OUT

 

= 5V)

4.974

4.976

4.978

4.980

4.982

4.984

4.986

4.988

4.990

4.992

4.994

-40

-20

-10

0

20

40

85

125

I

LOAD

 = 150mA

V

IN

 

= 6V

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

TEMPERATURE (

°C)

Output Voltage vs. Temperature (V

OUT

 

= 5V)

V

OUT

 (V)

 

Temperature vs. Quiescent Current (V

OUT

 

= 5V)

0

10

20

30

40

50

60

70

80

-40

-20

-10

0

20

40

85

125

GND CURRENT (

μ

A) 

I

LOAD

 = 150mA

V

IN

 

= 6V

C

IN

 

= 1

μF

C

OUT

 

= 1

μF

TEMPERATURE (

°C)

10.0

1.0

0.1

0.0

0.01K 0.1K

1K

10K

100K

1000K

FREQUENCY (Hz)

Output Noise vs. Frequency

NOISE (

μ

V/

Hz)

R

LOAD

 = 50

Ω 

C

OUT 

= 1

μF

C

IN

 = 1

μF

1000

100

10

1

0.1

0.01

0

10 20 30 40 50 60 70 80 90 100

LOAD CURRENT (mA)

Stability Region vs. Load Current

C

OUT 

ESR

 

(Ω

)

C

OUT

 = 1

μ

to 10

μF

Stable Region

Stable Region

-30

-35

-40

-45

-50

-60

-55

-65

-70

-75

-80

0.01K 0.1K

1K

10K

100K 1000K

FREQUENCY (Hz)

Power Supply Rejection Ratio

PSRR (dB)

I

OUT 

=

 

10mA

V

INDC 

=

 

4V

V

INAC 

=

 

100mVp-p

V

OUT 

=

 

3V

C

IN 

=

 

0

C

OUT 

=

 

1

μF

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 2010 Microchip Technology Inc.

DS21353E-page 7

TC1070/TC1071/TC1187

V

OUT

V

SHDN

Measure Rise Time of 3.3V LDO

Conditions: C

IN

 = 1

μF, C

OUT

 = 1

μF, I

LOAD

 = 100mA, V

IN

 = 4.3V,

Temp = 25

°C, Fall Time = 184μS

V

SHDN

Measure Rise Time of 5.0V LDO

Conditions: C

IN

 = 1

μF, C

OUT

 = 1

μF, I

LOAD

 = 100mA, V

IN

 = 6V,

Temp = 25

°C, Fall Time = 192μS

V

OUT

Thermal Shutdown Response of 5.0V LDO

Conditions: V

IN

 = 6V, C

IN

 = 0

μF, C

OUT

 = 1

μF

I

LOAD

 was increased until temperature of die reached about 160

°C, at

which time integrated thermal protection circuitry shuts the regulator
off when die temperature exceeds approximately 160

°C. The regulator

remains off until die temperature drops to approximately 150

°C.

V

OUT

Measure Fall Time of 3.3V LDO

Conditions: C

IN

 = 1

μF, C

OUT

 = 1

μF, I

LOAD

 = 100mA, V

IN

 = 4.3V,

Temp = 25

°C, Fall Time = 52μS

V

OUT

V

SHDN

Measure Fall Time of 5.0V LDO

Conditions: C

IN

 = 1

μF, C

OUT

 = 1

μF, I

LOAD

 = 100mA, V

IN

 = 6V,

Temp = 25

°C, Fall Time = 88μS

V

OUT

V

SHDN

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TC1070/TC1071/TC1187

DS21353E-page 8

 2010 Microchip Technology Inc.

3.0

PIN DESCRIPTIONS

The descriptions of the pins are listed in 

Table 3-1

.

3.1

Input Voltage Supply (V

IN

)

Connect unregulated input supply to the V

IN

 pin. If

there is a large distance between the input supply and
the LDO regulator, some input capacitance is
necessary for proper operation. A 1 µF capacitor
connected from V

IN

 to ground is recommended for

most applications.

3.2

Ground (GND)

Connect the unregulated input supply ground return to
GND. Also connect the negative side of the 1 µF typical
input decoupling capacitor close to GND and the
negative side of the output capacitor C

1

 to GND.

3.3

Shutdown Control Input (SHDN)

The regulator is fully enabled when a logic high is
applied to this input. The regulator enters shutdown
when a logic low is applied to this input. During
shutdown, output voltage falls to zero and supply
current is reduced to 0.5 µA (maximum).

3.4

Output Voltage Adjust (ADJ)

Output voltage setting is programmed with a resistor
divider from V

OUT

 to this input. 

3.5

Regulated Voltage Output (V

OUT

)

Connect the output load to V

OUT

 of the LDO. Also

connect the positive side of the LDO output capacitor
as close as possible to the V

OUT

 pin.

TABLE 3-1:

PIN FUNCTION TABLE

TC1070/TC1071/TC1187

Symbol

Description

SOT-23

1

V

IN

Unregulated supply input

2

GND

Ground terminal

3

SHDN

Shutdown control input 

4

ADJ

Output voltage adjust terminal

5

V

OUT

Regulated voltage output

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 2010 Microchip Technology Inc.

DS21353E-page 9

TC1070/TC1071/TC1187

4.0

DETAILED DESCRIPTION

The TC1070, TC1071 and TC1187 are adjustable
output voltage regulators. (If a fixed version is desired,
please see the TC1014/TC1015/TC1185 data sheet –
DS21335.) Unlike bipolar regulators, the TC1070,
TC1071 and TC1187 supply current does not increase
with load current. In addition, V

OUT

 remains stable and

within regulation over the entire 0 mA to I

OUTmax

 oper-

ating load current range (an important consideration in
RTC and CMOS RAM battery back-up applications). 

Figure 4-1

 shows a typical application circuit. The

regulator is enabled any time the shutdown input
(SHDN) is at or above V

IH

, and shutdown (disabled)

when SHDN is at or below V

IL

. SHDN may be

controlled by a CMOS logic gate or I/O port of a
microcontroller. If the SHDN input is not required, it
should be connected directly to the input supply. While
in shutdown, supply current decreases to 0.05 µA
(typical) and V

OUT

 falls to zero volts.

FIGURE 4-1:

Battery-Operated Supply.

4.1

Adjust Input

The output voltage setting is determined by the values
of R

1

 and R

2

 (see 

Equation 4-1

). The ohmic values of

these resistors should be between 470K and 3M to
minimize bleeder current.

The output voltage setting is calculated using the
following equation:

EQUATION 4-1:

The voltage adjustment range of the TC1070, TC1071
and TC1187 is from V

REF

 to (V

IN

 – 0.05V).

4.2

Output Capacitor

A 1 µF (minimum) capacitor from V

OUT

 to ground is

recommended. The output capacitor should have an
effective series resistance greater than 0.1

 and less

than 5.0

, and a resonant frequency above 1 MHz.

Aluminum electrolytic or tantalum capacitor types can
be used. (Since many aluminum electrolytic capacitors
freeze at approximately -30°C, solid tantalums are rec-
ommended for applications operating below -25°C.)
When operating from sources other than batteries,
supply-noise rejection and transient response can be
improved by increasing the value of the input and
output capacitors and employing passive filtering
techniques.

4.3

Input Capacitor

A 1 µF capacitor should be connected from V

IN

 to

GND if there is more than 10 inches of wire between
the regulator and the AC filter capacitor, or if a battery
is used as power source.

TC1070
TC1071
TC1187

V

OUT

SHDN

GND

C2 +

V

IN

+2.45V

Shutdown Control

(from Power Control Logic)

C1

1 µF

+

3.0V

Battery

+

 

R1

470K

1

5

2

4

3

ADJ

R2

470K

1 µF

V

OUT

V

REF

R

1

R

2

------

1

=

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TC1070/TC1071/TC1187

DS21353E-page 10

 2010 Microchip Technology Inc.

5.0

THERMAL CONSIDERATIONS

5.1

Thermal Shutdown 

Integrated thermal protection circuitry shuts the
regulator off when die temperature exceeds 160°C.
The regulator remains off until the die temperature
drops to approximately 150°C.

5.2

Power Dissipation 

The amount of power the regulator dissipates is
primarily a function of input and output voltage, and
output current. The following equation is used to
calculate worst-case actual power dissipation:

EQUATION 5-1:

The maximum allowable power dissipation
(

Equation 5-2

) is a function of the maximum ambient

temperature (T

Amax

), the maximum allowable die

temperature (T

Jmax

) and the thermal resistance from

junction-to-air (

JA

). The 5-Pin SOT-23 package has a

JA

 of approximately 220° C/Watt.

EQUATION 5-2:

Equation 5-1

 can be used in conjunction with

Equation 5-2

 

to ensure regulator thermal operation is

within limits. For example:

Actual power dissipation:

Maximum allowable power dissipation:

In this example, the TC1070 dissipates a maximum of
26.2 mW which is below the allowable limit of 318 mW.
In a similar manner, 

Equation 5-1

 and 

Equation 5-2

 can

be used to calculate maximum current and/or input
voltage limits.

5.3

Layout Considerations

The primary path of heat conduction out of the package
is via the package leads. Therefore, layouts having a
ground plane, wide traces at the pads, and wide power
supply bus lines combine to lower 

JA

  and therefore

increase the maximum allowable power dissipation
limit.

P

D

 

 (V

INmax

 – V

OUTmin

)I

LOADmax

Where:

P

D

= Worst-case actual power dissipation

V

INmax

= Maximum voltage on V

IN

V

OUTmin

= Minimum regulator output voltage

I

LOADmax

= Maximum output (load) current

where all terms are previously defined.

P

Dmax

T

Jmax

T

Amax

J A

----------------------------------------

=

Given:

V

INmax

=

3.0V  ±10%

V

OUTmin

=

2.7V  –  2%

I

LOADmax

=

40 mA

T

Jmax

=

+125°C

T

Amax

=

+55°C

Find:

1. Actual power dissipation

2. Maximum allowable dissipation

P

D

 (V

INmax

 – V

OUTmin

)I

LOADmax

= [(3.0 x 1.10) – (2.7 x .0.98)]40 x 10

–3

= 26.2 mW

= 318 mW

125

55

220

-------------------------

=

P

Dmax

T

Jmax

T

Amax

JA

----------------------------------------

=

Maker
Microchip Technology Inc.
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