Comparator with 1.25% Reference and Adjustable Hysteresis

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DS20005758A-page 1

MIC841/2

Features

• 1.5V to 5.5V Operating Range
• 1.5 μA Typical Supply Current
• ±1.25% Voltage Threshold Accuracy
• 10 nA Maximum Input Leakage Current Over 

Temperature

• 10 μs Propagation Delay
• Externally Adjustable Hysteresis (MIC841)
• Internal 20 mV Hysteresis (MIC842)
• Output Options:

- Push-Pull, Active-High
- Push-Pull, Active-Low
- Open-Drain, Active-Low

• Open-Drain Output can be Pulled to 6V 

Regardless of V

DD

• Immune to Brief Input Transients
• Teeny 5-Pin SC-70 Package
• 6-Pin 1.6 mm x 1.6 mm TDFN (MIC841)
• 4-Pin 1.2 mm x 1.6 mm TDFN (MIC842)

Applications

• Smartphones
• PDAs
• Precision Battery Monitoring
• Battery Chargers

General Description

The MIC841 and MIC842 are micro-power,
precision-voltage comparators with an on-chip voltage
reference.
Both devices are intended for voltage monitoring
applications. External resistors are used to set the
voltage monitor threshold. When the threshold is
crossed, the outputs switch polarity.
The MIC842 incorporates a voltage reference and
comparator with fixed internal hysteresis; two external
resistors are used to set the switching threshold
voltage. The MIC841 provides a similar function with
user adjustable hysteresis; this part requires three
external resistors to set the upper and lower thresholds
(the difference between the threshold voltages being
the hysteresis voltage).
Both the MIC841 and MIC842 are available with
push-pull or open-drain output stage. The push-pull
output stage is configured either active-high or
active-low; the open-drain output stage is only
configured active-low.
Supply current is extremely low (1.5 μA, typical),
making it ideal for portable applications.
The MIC841/2 is supplied in the Teeny 5-pin SC-70,
6-pin 1.6 mm × 1.6 mm Thin DFN (MIC841), and 4-pin
1.2 mm × 1.6 mm Thin DFN (MIC842) packages.

Package Types

MIC841

SC-70-5 (C5)

LTH GND HTH

OUT

VDD

Yxx

3

2

1

4

5

MIC841

6-Pin TDFN (MT)

LTH

GND

HTH

OUT

NC

VDD

1

2

3

6

5

4

EP

MIC842

SC-70-5 (C5)

NC GND INP

OUT

VDD

Yxx

3

2

1

4

5

MIC842

4-Pin TDFN (MT)

OUT

GND

VDD

INP

1

2

3

4

EP

Comparator with 1.25% Reference and Adjustable Hysteresis

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MIC841/2

DS20005758A-page 2

 2017 Microchip Technology Inc.

Typical Application Circuits

MIC841

Threshold Detection with Adjustable Hysteresis

HTH

OUT

VDD
LTH

GND

MIC841

V

IN

R1

R2

R3

V

OUT

V

DD

V

LTH

 > V

HTH

V

REF 

= 1.24V

9”9

DD

”9

MIC842

Threshold Detection with Internal Fixed Hysteresis

INP

OUT

VDD

GND

V

IN

R1

V

OUT

V

DD

V

REF

 = 1.24V

9”9

DD

”9

MIC842

R2

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DS20005758A-page 3

MIC841/2

1.0

FUNCTIONAL BLOCK DIAGRAMS

Note:

 Block diagrams show SC-70 package pin numbers.

FIGURE 1-1:

MIC841H Block Diagram

FIGURE 1-2:

MIC841L Block Diagram

FIGURE 1-3:

MIC841N Block Diagram

FIGURE 1-4:

MIC842H Block Diagram

FIGURE 1-5:

MIC842L Block Diagram

FIGURE 1-6:

MIC842N Block Diagram

GND

V

DD

OUT

1.24V

BANDGAP

REFERENCE

LOW-VOLTAGE

DETECT

HIGH-VOLTAGE

DETECT

R

S

Q

Q

LTH

HTH

V

LTH

V

HTH

MIC841H

V

IN

3

1

2

4

5

V

DD

GND

V

DD

OUT

1.24V

BANDGAP

REFERENCE

LOW-VOLTAGE

DETECT

HIGH-VOLTAGE

DETECT

R

S

Q

Q

LTH

HTH

V

LTH

V

HTH

MIC841L

V

DD

V

IN

3

1

2

4

5

GND

V

DD

OUT

1.24V

BANDGAP

REFERENCE

LOW-VOLTAGE

DETECT

HIGH-VOLTAGE

DETECT

R

S

Q

Q

LTH

HTH

V

LTH

V

HTH

MIC841N

V

IN

3

1

2

4

5

V

DD

GND

V

IN

1.24V

BANDGAP

REFERENCE

HIGH-VOLTAGE

DETECT

INP

V

TH

MIC842H

2

1

5

V

DD

OUT

4

V

DD

GND

V

IN

1.24V

BANDGAP

REFERENCE

HIGH-VOLTAGE

DETECT

INP

V

TH

MIC842L

2

1

5

V

DD

OUT

4

V

DD

GND

V

IN

OUT

1.24V

BANDGAP

REFERENCE

HIGH-VOLTAGE

DETECT

INP

V

TH

MIC842N

4

2

1

5

V

DD

V

DD

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MIC841/2

DS20005758A-page 4

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2.0

ELECTRICAL CHARACTERISTICS

Absolute Maximum Ratings †

Supply Voltage (V

DD

) ................................................................................................................................... –0.3V to +7V

Input Voltage (V

INP

, V

LTH

,V

HTH

) ..................................................................................................................................+7V

Output Current (I

OUT

) ............................................................................................................................................±20 mA

ESD Rating

(

1

)

.............................................................................................................................................................1 kV

Operating Ratings ‡

Supply Voltage (V

DD

) ................................................................................................................................ +1.5V to +5.5V

Input Voltage (V

INP

, V

LTH

,V

HTH

) ........................................................................................................................ 0V to +6V

V

OUT

 (‘H’ and ‘L’ versions) ......................................................................................................................................... V

DD

V

OUT

 (‘N’ version)........................................................................................................................................................+6V

 Notice: Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the device.

This is a stress rating only and functional operation of the device at those or any other conditions above those indicated
in the operational sections of this specification is not intended. Exposure to maximum rating conditions for extended
periods may affect device reliability.
‡ Notice:

 The device is not guaranteed to function outside its operating ratings.

Note 1:

Devices are ESD sensitive. Handling precautions are recommended. Human body model, 1.5 kΩ in series
with 100 pF.

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DS20005758A-page 5

MIC841/2

TABLE 2-1:

ELECTRICAL CHARACTERISTICS

Electrical Characteristics:

 1.5V ≤ V

DD

 ≤ 5.5V; T

A

 = 25°C. –40°C ≤ T

A

 ≤ +85°C, unless noted. (

Note 1

)

.

Parameters

Min.

Typ.

Max.

Units

Conditions

Supply Current (I

DD

)

1.5

3

µA

Output not asserted

Input Leakage Current (I

INP

)

0.005

10

nA

Reference Voltage (V

REF

)

1.225

1.240

1.256

V

0°C ≤ T

A

 ≤ 85°C

1.219

1.240

1.261

–40°C ≤ T

A

 ≤ 85°C

Hysteresis Voltage (V

HYST

(

Note 2

)

8

20

35

mV

MIC842 only

Propagation Delay (t

D

)

12

50

µs

V

INP

 = 1.352V to 1.128V

8

50

V

INP

 = 1.143V to 1.367V

Output Voltage-Low (V

OUT

(

Note 3

)

0.05

0.3

V

I

SINK

 = 1.6 mA, V

DD

 ≥ 1.6V

0.005

0.4

I

SINK

 = 100 µA, V

DD

 ≥ 1.2V

Output Voltage-High (V

OUT

(

Note 3

)

0.99V

DD

I

SOURCE

 = 500 µA, V

DD

 ≥ 1.6V

0.99V

DD

I

SOURCE

 = 50 µA, V

DD

 ≥ 1.2V

Note 1:

Specification for packaged product only.

2:

V

HTH

 = V

REF

 + V

HYST

.

3:

V

DD

 operating range is 1.5V to 5.5V. Output is guaranteed to be de-asserted down to V

DD

 = 1.2V.

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MIC841/2

DS20005758A-page 6

 2017 Microchip Technology Inc.

TEMPERATURE SPECIFICATIONS

Parameters

Sym.

Min.

Typ.

Max.

Units

Conditions

Temperature Ranges
Maximum Junction Temperature 

T

J

+150

°C

Note 1

Storage Temperature Range

T

S

–65

+150

°C

Ambient Temperature Range

T

A

–40

+85

°C

Lead Temperature

+260

°C

Soldering, 10s

Package Thermal Resistances
SC-70-5

JA

256.5

°C/W

6-Pin 1.6 mm x 1.6 mm TDFN

JA

92

°C/W

4-Pin 1.2 mm x 1.6 mm TDFN

JA

173

°C/W

Note 1:

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., T

A

, T

J

JA

). Exceeding the 

maximum allowable power dissipation will cause the device operating junction temperature to exceed the 
maximum +150°C rating. Sustained junction temperatures above +150°C can impact the device reliability.

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DS20005758A-page 7

MIC841/2

3.0

PIN DESCRIPTIONS

The descriptions of the pins are listed in 

Table 3-1

 and 

Table 3-2

.

TABLE 3-1:

MIC841 PIN FUNCTION TABLE

Pin Number

SC-70

Pin Number

TDFN

Symbol

Description

1

3

HTH

High Threshold Input. HTH and LTH monitor external 
voltages.

2

2

GND

Ground.

3

1

LTH

Low Threshold Input. LTH and HTH monitor external voltages.

4

6

OUT

(“H” Version) Active-Low Push-Pull Output. OUT asserts low 
when V

LTH

 < V

REF

. OUT remains low until V

HTH

 > V

REF

.

OUT

(“L” Version) Active-High Push-Pull Output. OUT asserts high 
when V

LTH

 < V

REF

. OUT remains high until V

HTH

 > V

REF

.

OUT

(“N” Version) Active-Low, Open-Drain Output. OUT asserts 
low when V

LTH

 < V

REF

. OUT remains low until V

HTH

 > V

REF

.

5

4

VDD

Power Supply Input.

5

NC

No Connect. Not internally connected.

EP

ePAD

Heatsink Pad. Connect to GND for best thermal performance.

TABLE 3-2:

MIC842 PIN FUNCTION TABLE

Pin Number

SC-70

Pin Number

TDFN

Symbol

Description

1

3

INP

Threshold Input. INP monitors an external voltage.

2

2

GND

Ground.

3

NC

No Connect. Not internally connected.

4

1

OUT

(“H” Version) Active-Low, Push-Pull Output. OUT asserts low 
when V

INP

 < V

REF

. OUT remains low until V

INP

 > (V

REF

 + 

V

HYST

). 

OUT

(“L” Version) Active-High, Push-Pull Output. OUT asserts high 
when V

INP

 < V

REF

. OUT remains high until V

INP

 > (V

REF

 + 

V

HYST

).

OUT

(“N” Version) Active-Low, Open-Drain Output. OUT asserts 
low when V

INP

 < V

REF

. OUT remains low until V

INP

 > (V

REF

 + 

V

HYST

).

5

4

VDD

Power Supply Input.

EP

ePAD

Heatsink Pad. Connect to GND for best thermal performance.

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MIC841/2

DS20005758A-page 8

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4.0

APPLICATION INFORMATION

4.1

Output

The MIC841N and MIC842N outputs are an open-drain
MOSFET, so most applications will require a pull-up
resistor. The value of the resistor should not be too
large or leakage effects may dominate. 470 kΩ is the
maximum recommended value. Note that the output of
the “N” version may be pulled up as high as 6V
regardless of the IC’s supply voltage. The “H” and “L”
versions of the MIC841 and MIC842 have a push-pull
output stage with a diode clamped to V

DD

. Thus, the

maximum output voltage of the “H” and “L” versions is
V

DD

 (see 

Table 2-1

).

When working with large resistors on the input to the
devices, a small amount of leakage current can cause
voltage offsets that degrade system accuracy. The
maximum recommended total resistance from V

IN

 to

ground is 3 MΩ. The accuracy of the resistors can be
chosen based upon the accuracy required by the
system. The inputs may be subjected to voltages as
high as 6V steady-state without adverse effects of any
kind regardless of the IC’s supply voltage. This applies
even if the supply voltage is zero. This permits the
situation in which the IC’s supply is turned off, but
voltage is still present on the inputs (see 

Table 2-1

).

4.2

Programming the MIC841 
Thresholds

The low-voltage threshold is calculated using

Equation 4-1

.

EQUATION 4-1:

The high-voltage threshold is calculated using

Equation 4-2

.

EQUATION 4-2:

In order to provide the additional criteria needed to
solve for the resistor values, the resistors can be
selected such that they have a given total value, that is,
R1 + R2 + R3 = R

TOTAL

. A value such as 1 MΩ for

R

TOTAL

 is a reasonable value because it draws

minimum current but has no significant effect on
accuracy.

FIGURE 4-1:

MIC841 Example Circuit

Once the desired trip points are determined, set the
V

IN(HI)

 threshold first.

For example, use a total of 1 MΩ = R1 + R2 + R3. For
a typical single-cell lithium ion battery, 3.6V is a good
“high threshold” because at 3.6V the battery is
moderately charged. Solving for R3:

EQUATION 4-3:

Once R3 is determined, the equation for V

IN(LO)

 can be

used to determine R2. A single lithium-ion cell, for
example, should not be discharged below 2.5V. Many
applications limit the drain to 3.1V.
Using 3.1V for the V

IN(LO)

 threshold allows the

calculation of the two remaining resistor values.

EQUATION 4-4:

The accuracy of the resistors can be chosen based
upon the accuracy required by the system.

V

IN LO

V

REF

R1

R2

R3

+

+

R2

R3

+

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

=

Where:

V

REF

1.240V

V

IN HI

V

REF

R1

R2

R3

+

+

R3

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

=

Where:

V

REF

1.240V

V

IN

R1

604k 1%

R2

56k 1%

R3

340k 1%

V

DD

VDD

LTH

HTH

OUT

GND

470k

V

OUT

MIC841N

V

IN HI

3.6V

1.24V

1M

R3

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

=

=

Solve:

R3

344 kΩ

V

IN LO

3.1V

1.24V

1M

R2

344k

+

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

=

=

Solve:

R2

56 kΩ

R1

1 MΩ - R2 - R3

R1

600 kΩ

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DS20005758A-page 9

MIC841/2

FIGURE 4-2:

Output Response and 

Hysteresis

4.3

Programming the MIC842 
Thresholds

The voltage threshold is calculated using 

Equation 4-5

.

EQUATION 4-5:

FIGURE 4-3:

MIC842 Example Circuit

In order to provide the additional criteria needed to
solve for the resistor values, the resistors can be
selected such that they have a given total value, that is,
R1 + R2 = R

TOTAL

. A value such as 1 MΩ for R

TOTAL

 is

a reasonable value because it draws minimum current,
but has no significant effect on accuracy.

4.4

Input Transients

The MIC841/2 is inherently immune to very short
negative-going “glitches.” Very brief transients may
exceed the V

IN(LO)

 threshold without tripping the

output.
As shown in 

Figure 4-4

, the narrower the transient, the

deeper the threshold overdrive that will be ignored by
the MIC841/2. The graph represents the typical
allowable transient duration for a given amount of
threshold overdrive that will not generate an output.

FIGURE 4-4:

Input Transient Response

V

IN LO

V

REF

R1

R2

+

R2

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

=

Where:

V

REF

1.240V

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MIC841/2

DS20005758A-page 10

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5.0

PACKAGING INFORMATION

5.1

Package Marking Information

5-Pin SC-70*

Example

XXX
NNN

4-Pin TDFN*

Example

XX

B14
408

6-Pin TDFN*

Ÿ

BL

Ÿ

Device

Marking

MIC841H      B13
MIC841L       B14
MIC841N      B15
MIC842H      B16
MIC842L       B17
MIC842N      B18

Device

Marking

MIC841H      BH
MIC841L       BL
MIC841N      BN
MIC842H      HB
MIC842L       HL
MIC842N      HN

Legend:

XX...X

Product code or customer-specific information

Y

Year code (last digit of calendar year)

YY

Year code (last 2 digits of calendar year)

WW

Week code (week of January 1 is week ‘01’)

NNN

Alphanumeric traceability code

  

Pb-free JEDEC

®

 designator for Matte Tin (Sn)

*

This package is Pb-free. The Pb-free JEDEC designator (     )
can be found on the outer packaging for this package.

●, ▲, ▼ Pin one index is identified by a dot, delta up, or delta down (triangle
mark).

Note

:

In the event the full Microchip part number cannot be marked on one line, it will
be carried over to the next line, thus limiting the number of available
characters for customer-specific information. Package may or may not include
the corporate logo.
Underbar (_) and/or Overbar (⎯) symbol may not be to scale.

3

e

3

e

Maker
Microchip Technology Inc.
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