2011-2014 Microchip Technology Inc.
DS20002281C-page 1
MTD6505
Features
• 180° Sinusoidal Drive for High Efficiency and Low
Acoustic Noise
• Position Sensorless BLDC Drivers
(no Hall Effect Sensor required)
• Integrated Power Transistors
• Supports 2V to 5.5V Power Supplies
• Programming Resistor (R
PROG
) Settings to Fit
Motor Constant (K
M
) Range from 3.25 mV/Hz to
52 mV/Hz
• Direction Control:
- Forward direction: connect DIR pin to GND or
leave floating
- Reverse direction: connect DIR pin to V
BIAS
or 3V
• Speed Control through Power Supply Modulation
(PSM) and/or Pulse-Width Modulation (PWM)
• Built-in Frequency Generator (FG Output Signal)
• Built-in Lockup Protection and Automatic
Recovery Circuit
• Built-in Overcurrent Limitation
• Built-in Thermal Shutdown Protection
• Built-in Overvoltage Protection
• No External Tuning Required
• Available Package:
10-Lead 3mm x 3mm UDFN
Applications
• Notebook CPU Cooling Fans
• 5V 3-Phase BLDC
Description
The MTD6505 device is a 3-phase, full-wave
sensorless driver for brushless DC (BLDC) motors. It
features 180° sinusoidal drive, high-torque output and
silent drive. With the adaptive features, parameters and
wide range of power supplies (2V to 5.5V), the
MTD6505 is intended to cover a broad range of motor
characteristics, while requiring minimum external
components. Speed control can be achieved through
either PSM or PWM.
The compact packaging and the minimal bill of
materials make the MTD6505 device extremely
cost-efficient in fan applications. For example, the CPU
cooling fans in notebook computers require designs
that provide low acoustic noise, low mechanical
vibration, and are highly efficient. The frequency
generator (FG) output enables precision speed control
in closed-loop applications.
The MTD6505 device includes Lockup Protection mode
to turn off the output current when the motor is in a lock
condition, with an automatic recovery feature to restart
the fan when the lock condition is removed. Motor
overcurrent limitation and thermal shutdown protection
are included for safety-enhanced operations.
The MTD6505 is available in a compact, thermally-
enhanced,
10-lead 3 mm x 3 mm UDFN package.
Package Types
MTD6505
3x3 UDFN*
V
BIAS
R
PROG
OUT2
FG
PWM
DIR
V
DD
GND
1
2
3
5
10
9
8
6
OUT1
OUT3
4
7
EP
11
*Includes Exposed Thermal Pad (EP); see
Table 3-1
.
3-Phase Sinusoidal Sensorless Brushless Motor Driver
MTD6505
DS20002281C-page 2
2011-2014 Microchip Technology Inc.
Functional Block Diagram
Thermal
Protection
V
BIAS
OUT1
OUT2
CPU + Peripherals
PWM
FG
OUT3
V
DD
Short-Circuit
Protection
O
u
tput
Dr
iv
e
C
ir
c
ui
t
Motor Phase
Detection
Circuit
Overcurrent
Protection
GND
DIR
Nonvolatile
Memory
R
PROG
Sense
R
PROG
V
DD
Adjustable
K
M
2011-2014 Microchip Technology Inc.
DS20002281C-page 3
MTD6505
Typical Application
Recommended External Components for Typical Application
Element
Type/Value
Comment
C1
1 µF
Connect as close as possible to IC input pins
C2
1 µF
Connect as close as possible to IC input pins
R1
10 kΩ
Connect to V
LOGIC
on microcontroller side (FG Pull-Up)
R2
3.9 kΩ or 24 kΩ
Select appropriate programming resistor value, see
Table 4-2
MTD
6505
1
2
3
4
5
10
9
8
7
6
FG
V
BIAS
OUT1
OUT2
GND
OUT3
V
DD
DIR
PWM
R2
C1
V
DD
C2
V
DD
R1
K
M0
K
M3
K
M1, 2
R
PROG
V
BIAS
V
BIAS
MTD6505
DS20002281C-page 4
2011-2014 Microchip Technology Inc.
NOTES:
2011-2014 Microchip Technology Inc.
DS20002281C-page 5
MTD6505
1.0
ELECTRICAL
CHARACTERISTICS
Absolute Maximum Ratings†
Power Supply Voltage (V
DD_MAX
) ...................... -0.7 to +7.0V
Maximum Output Voltage (V
OUT_MAX
) ............... -0.7 to +7.0V
Maximum Output Current
(
1
)
(I
OUT_MAX
) ....................1000 mA
FG Maximum Output Voltage (V
FG_MAX
) ........... -0.7 to +7.0V
FG Maximum Output Current (I
FG_MAX
) ......................5.0 mA
V
BIAS
Maximum Voltage (V
BIAS_MAX
) ................ -0.7 to +4.0V
PWM Maximum Voltage (V
PWM_MAX
) ................ -0.7 to +7.0V
Allowable Power Dissipation
(
2
)
(P
D_MAX
).........................1.5W
Maximum Junction Temperature (T
J
).......................... +150°C
ESD protection on all pins
2 kV
† Notice:
Stresses above those listed under “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 listings of this specification
is not implied. Exposure to maximum rating conditions
for extended periods may affect device reliability.
Note 1:
I
OUT
is also internally limited, according
to the limits defined in the
“Electrical
Characteristics”
table.
2:
Reference Printed Circuit Board (PCB),
according to JEDEC standard EIA/JESD
51-9.
ELECTRICAL CHARACTERISTICS
Electrical Specifications:
Unless otherwise specified, all limits are established for V
DD
= 2.0V to 5.5V, T
A
= +25°C
Parameters
Sym.
Min.
Typ.
Max.
Units
Conditions
Power Supply Voltage
V
DD
2
—
5.5
V
Power Supply Current
I
VDD
—
5
10
mA
V
DD
= 5V
Standby Current
I
VDD_STB
—
30
40
µA
PWM = 0V, V
DD
= 5V
(Standby mode)
OUTX
High Resistance
R
ON(H)
—
0.75
1.1
Ω
I
OUT
= 0.5A, V
DD
= 5V
Note 1
OUTX
Low Resistance
R
ON(L)
—
0.75
1.3
Ω
I
OUT
= 0.5A, V
DD
= 5V
Note 1
OUTX
Total Resistance
R
ON(H+L)
—
1.5
2.4
Ω
I
OUT
= 0.5A, V
DD
= 5V
Note 1
V
BIAS
Internal
Supply Voltage
V
BIAS
—
3
—
V
V
DD
= 3.2V to 5.5V
—
V
DD
– 0.2
—
V
V
DD
< 3.2V
PWM Input Frequency
f
PWM
1
—
100
kHz
PWM Input H Level
V
PWM_H
0.55
V
DD
—
V
DD
V
V
DD
4.5V
PWM Input L Level
V
PWM_L
0
—
0.2
V
DD
V
V
DD
4.5V
PWM Internal Pull-Up
Resistor
R
PWM_0
—
266
—
kΩ
PWM = 0V
PWM Internal Pull-Up
Resistor
R
PWM
—
133
—
kΩ
PWM duty-cycle > 0%
DIR Input H Level
V
DIR_H
V
BIAS
– 0.5
—
V
BIAS
V
V
DD
4.5V
DIR Input L Level
V
DIR_L
0
—
0.2
V
DD
V
V
DD
4.5V
DIR Internal Pull-Down
Resistor
R
DIR
100
—
200
kΩ
FG Output Pin Low-
Level Voltage
V
OL_FG
—
—
0.25
V
I
FG
= -1 mA
FG Output Pin Leakage
Current
I
LH_FG
– 10
—
10
µA
V
FG
= 5.5V
Lock Protection
Operating Time
T
RUN
—
0.5
—
s
Lock Protection Waiting
Time
T
WAIT
4.5
5
5.5
s
Note 2
Overcurrent Protection
I
OC_MOT
—
750
—
mA
Note 3
Overvoltage Protection
V
OV
—
7.2
—
V
MTD6505
DS20002281C-page 6
2011-2014 Microchip Technology Inc.
Short Protection on
High Side
I
OC_SW_H
—
2.57
—
A
Short Protection on
Low Side
I
OC_SW_L
—
-2.83
—
A
Thermal Shutdown
T
SD
—
170
—
°C
Thermal Shutdown
Hysteresis
T
SD_HYS
—
25
—
°C
Note 1:
Minimum and maximum parameters are not production tested and are specified by design and validation.
2:
Related to the internal oscillator frequency (see
Figure 2-1
).
3:
750 mA is the standard option for MTD6505. Additional overcurrent protection levels are available upon
request. Please contact factory for different overcurrent protection values.
TEMPERATURE SPECIFICATIONS
Electrical Specifications:
Unless otherwise specified, all limits are established for V
DD
= 2.0V to 5.5V, T
A
= +25°C.
Parameters
Sym.
Min.
Typ.
Max.
Units
Conditions
Temperature Ranges
Operating Temperature
T
OPR
-40
—
+125
°C
Storage Temperature Range
T
STG
-55
—
+150
°C
Thermal Package Resistances
Thermal Resistance, 10LD-UDFN 3x3
JA
—
96.6
—
°C/W
JC
—
12
—
°C/W
ELECTRICAL CHARACTERISTICS (CONTINUED)
Electrical Specifications:
Unless otherwise specified, all limits are established for V
DD
= 2.0V to 5.5V, T
A
= +25°C
Parameters
Sym.
Min.
Typ.
Max.
Units
Conditions
2011-2014 Microchip Technology Inc.
DS20002281C-page 7
MTD6505
2.0
TYPICAL PERFORMANCE CURVES
Note:
Unless indicated, T
A
= +25°C, V
DD
= 2.0V to 5.5V, OUT1, 2, 3 and PWM open.
FIGURE 2-1:
Oscillator Frequency
Deviation vs. Temperature.
FIGURE 2-2:
Internal Regulated Voltage
(V
BIAS
) vs. Temperature.
FIGURE 2-3:
Internal Regulated Voltage
(V
BIAS
) vs. Supply Voltage (V
DD
).
FIGURE 2-4:
Inputs (PWM, DIR) V
IL
vs.
Temperature.
FIGURE 2-5:
Inputs (PWM, DIR) V
IH
vs.
Temperature.
FIGURE 2-6:
Outputs R
ON
High-Side
Resistance vs. Temperature.
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.
-3
-2.5
-2
-1.5
-1
-0.5
0
0.5
1
or Frequeny
Deviation
(%
)
V
DD
= 5.5V
V
DD
= 2V
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0.5
1
-40 -25 -10 5
20 35 50 65 80 95 110 125
Oscillator Frequency
Deviation
(%
)
Temperature (°C)
V
DD
= 5.5V
V
DD
= 2V
3 04
3.06
3.08
3.1
3.12
3.14
V
BIA
S
(V)
3
3.02
3.04
3.06
3.08
3.1
3.12
3.14
-40 -25 -10
5
20 35 50 65 80 95 110 125
V
BIA
S
(V)
Temperature (°C)
1
1.5
2
2.5
3
3.5
V
BIA
S
(V)
0
0.5
1
1.5
2
2.5
3
3.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
V
BIA
S
(V)
V
DD
(V)
1
1.5
2
2.5
PWM V
IL
(V)
VDD = 5.5
VDD = 5.5
V
DD
= 5.5V
V
DD
= 2V
0
0.5
1
1.5
2
2.5
-40 -25 -10
5
20 35 50 65 80 95 110 125
PWM V
IL
(V)
Temperature (°C)
VDD = 5.5
VDD = 5.5
V
DD
= 5.5V
V
DD
= 2V
1
1.5
2
2.5
3
PWM V
IH
(V)
V
DD
= 5.5V
V
DD
= 2V
0
0.5
1
1.5
2
2.5
3
-40 -25 -10
5
20 35 50 65 80 95 110 125
PWM V
IH
(V)
Temperature (°C)
V
DD
= 5.5V
V
DD
= 2V
1 5
2
2.5
3
3.5
4
4.5
5
5.5
6
R
ON High Side (
)
V
DD
= 2V
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
-40 -25 -10
5
20 35 50 65 80 95 110 125
RON High Side (
)
Temperature (°C)
V
DD
= 5.5V
V
DD
= 2V
MTD6505
DS20002281C-page 8
2011-2014 Microchip Technology Inc.
Note:
Unless indicated, T
A
= +25°C, V
DD
= 2.0V to 5.5V, OUT1, 2, 3 and PWM open.
FIGURE 2-7:
Outputs R
ON
Low-Side
Resistance vs. Temperature.
FIGURE 2-8:
Supply Current vs.
Temperature.
FIGURE 2-9:
Standby Current vs.
Temperature.
FIGURE 2-10:
PWM Pull-Up Current vs.
Temperature.
FIGURE 2-11:
Typical Output on Start-Up.
FIGURE 2-12:
Typical Outputs on Closed
Loop.
2
2.5
3
3.5
4
4.5
5
5.5
6
O
N Low
Side
(
)
V
DD
= 2V
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
-40 -25 -10
5
20 35 50 65 80 95 110 125
RON Low
Side
(
)
Temperature (°C)
V
DD
= 5.5V
V
DD
= 2V
2
3
4
5
6
7
V
DD
Current (mA)
V
DD
= 2V
V
DD
= 5.5V
0
1
2
3
4
5
6
7
-40 -25 -10
5
20 35 50 65 80 95 110 125
I
VDD
Current (mA)
Temperature (°C)
V
DD
= 2V
V
DD
= 5.5V
20
30
40
50
60
D
_STB
Current (µA)
V
DD
= 5.5V
0
10
20
30
40
50
60
-40 -25 -10
5
20 35 50 65 80 95 110 125
I
VDD_STB
Current (µA)
Temperature (°C)
V
DD
= 5.5V
V
DD
= 2V
-30
-25
-20
-15
-10
-5
0
Pull-Up Current (µA)
V
DD
= 2V
-40
-35
-30
-25
-20
-15
-10
-5
0
-40 -25 -10
5
20 35 50 65 80 95 110 125
PWM
Pull-Up Current (µA)
Temperature (°C)
V
DD
= 2V
V
DD
= 5.5V
2011-2014 Microchip Technology Inc.
DS20002281C-page 9
MTD6505
3.0
PIN DESCRIPTIONS
The descriptions of the pins are listed in
Table 3-1
.
TABLE 3-1:
MTD6505 PIN FUNCTION TABLE
Pin
Number
Type
Name
Function
1
O
FG
Motor Speed Indication Output Pin
2
I
R
PROG
K
M
Parameter Setting with External Resistors Pin, see
Table 4-2
for values
3
—
V
BIAS
Internal Regulator Output Pin (for decoupling only)
4
O
OUT1
Single-Phase Coil Output Pin
5
O
OUT2
Single-Phase Coil Output Pin
6
—
GND
Negative Voltage Supply Pin (ground)
7
O
OUT3
Single-Phase Coil Output Pin
8
—
V
DD
Positive Voltage Supply Pin for Motor Driver
9
I
DIR
Motor Rotation Direction Pin
- Forward direction: connect this pin to GND or leave floating
- Reverse direction: connect this pin to V
BIAS
10
I
PWM
PWM Input Signal Pin for Speed Control
11
—
EP
Exposed Thermal Pad Pin (Connect to the ground plan for better thermal
dissipation)
Legend:
I = Input; O = Output
MTD6505
DS20002281C-page 10
2011-2014 Microchip Technology Inc.
NOTES: