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DRV8872-Q1
SLIS175 – NOVEMBER 2016
DRV8872-Q1 Automotive 3.6-A Brushed DC Motor Driver With Fault Reporting
1 Features
3 Description
•
The DRV8872-Q1 device is a brushed DC (BDC)
motor driver for infotainment, HUD projector
adjustment, motorized shifter knobs, and piezo horn
drivers. Two logic inputs control the H-bridge driver,
which consists of four N-channel MOSFETs that
provide bidirectional control of motors up to 3.6-A
peak current. The inputs can be pulse-width
modulated (PWM) to control motor speed, using a
choice of current-decay modes. Setting both inputs
low enters a low-power sleep mode.
1
•
•
•
•
•
•
•
•
•
•
AEC-Q100 Qualified for Automotive Applications:
– Device Temperature Grade 1: –40°C to
+125°C Ambient Operating Temperature
Range
– Device HBM ESD Classification Level 2
– Device CDM ESD Classification Level C4B
H-Bridge Motor Driver
– Drives One DC Motor, One Winding of a
Stepper Motor, or Other Loads
Wide 6.8-V to 45-V Operating Voltage
565-mΩ Typical RDS(on) (HS + LS)
3.6-A Peak Current Drive
PWM Control Interface
Integrated Current Regulation
Low-Power Sleep Mode
Fault Status Output Pin
Small Package and Footprint
– 8-Pin HSOP With PowerPAD™
– 4.9 × 6 mm
Integrated Protection Features
– VM Undervoltage Lockout (UVLO)
– Overcurrent Protection (OCP)
– Thermal Shutdown (TSD)
– Fault Reporting (nFAULT)
– Automatic Fault Recovery
The device is fully protected from faults and short
circuits, including undervoltage lockout (UVLO),
overcurrent protection (OCP), and thermal shutdown
(TSD). Faults are communicated by pulling the
nFAULT output low. When the fault condition is
removed, the device automatically resumes normal
operation.
Device Information(1)
PART NUMBER
DRV8872-Q1
PACKAGE
HSOP (8)
BODY SIZE (NOM)
4.90 mm × 6.00 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
2 Applications
•
•
•
•
The DRV8872-Q1 device features integrated current
regulation, based on an internal reference voltage
and the voltage on the ISEN pin, which is proportional
to motor current through an external sense resistor.
The ability to limit current to a known level can
significantly reduce the system power requirements
and bulk capacitance needed to maintain stable
voltage, especially for motor startup and stall
conditions.
Automotive Infotainment
HUD Projector Adjustment
Motorized Shifter Knobs
Piezo Horn Driver
H-Bridge States
Simplified Schematic
6.8 to 45 V
IN1
IN2
Controller
nFAULT
DRV8872-Q1
3.6 A
Brushed DC
Motor Driver
Current
Regulation
BDC
ISEN
Fault
Protection and
Reporting
Copyright © 2016, Texas Instruments Incorporated
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
DRV8872-Q1
SLIS175 – NOVEMBER 2016
www.ti.com
Table of Contents
1
2
3
4
5
6
7
Features ..................................................................
Applications ...........................................................
Description .............................................................
Revision History.....................................................
Pin Configuration and Functions .........................
Specifications.........................................................
1
1
1
2
3
3
6.1
6.2
6.3
6.4
6.5
6.6
3
4
4
4
5
6
9
Power Supply Recommendations...................... 14
9.1 Bulk Capacitance .................................................... 14
10 Layout................................................................... 15
10.1 Layout Guidelines .................................................
10.2 Layout Example ....................................................
10.3 Thermal Considerations.......................................
10.4 Power Dissipation .................................................
15
15
15
15
11 Device and Documentation Support ................. 17
11.1
11.2
11.3
11.4
11.5
11.6
Detailed Description .............................................. 7
7.1
7.2
7.3
7.4
8
Absolute Maximum Ratings ......................................
ESD Ratings..............................................................
Recommended Operating Conditions.......................
Thermal Information ..................................................
Electrical Characteristics...........................................
Typical Characteristics ..............................................
8.1 Application Information............................................ 11
8.2 Typical Application .................................................. 11
Overview ................................................................... 7
Functional Block Diagram ......................................... 7
Feature Description................................................... 8
Device Functional Modes........................................ 10
Documentation Support ........................................
Receiving Notification of Documentation Updates
Community Resources..........................................
Trademarks ...........................................................
Electrostatic Discharge Caution ............................
Glossary ................................................................
17
17
17
17
17
17
12 Mechanical, Packaging, and Orderable
Information ........................................................... 17
Application and Implementation ........................ 11
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
2
DATE
REVISION
NOTES
November 2016
*
Initial release.
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5 Pin Configuration and Functions
DDA Package
8-Pin HSOP With Exposed Thermal Pad
Top View
GND
1
IN2
2
IN1
3
nFAULT
4
Thermal
Pad
8
OUT2
7
ISEN
6
OUT1
5
VM
Pin Functions
PIN
NAME
NO.
TYPE
GND
1
IN1
3
IN2
2
ISEN
7
nFAULT
4
OUT1
6
OUT2
8
VM
5
PWR
PAD
—
—
DESCRIPTION
PWR
Logic ground
Connect to board ground.
I
Logic inputs
Controls the H-bridge output. Has internal pulldowns. (See Table 1.)
PWR
High-current ground path
If using current regulation, connect ISEN to a resistor (low-value,
high-power-rating) to ground. If not using current regulation, connect
ISEN directly to ground.
OD
Fault status (open-drain)
Low-level indicates UVLO, TSD, or OCP fault. Connect to a pullup
resistor.
H-bridge outputs
Connect directly to the motor, or other inductive load.
6.8-V to 45-V power
supply
Connect a 0.1-µF bypass capacitor to ground, as well as sufficient
bulk capacitance, rated for the VM voltage.
Thermal pad
Connect to board ground. For good thermal dissipation, use large
ground planes on multiple layers, and multiple nearby vias
connecting those planes.
O
6 Specifications
6.1 Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted) (1)
MIN
MAX
UNIT
Power supply voltage (VM)
–0.3
50
V
Logic input voltage (IN1, IN2)
–0.3
7
V
Fault pin (nFAULT)
–0.3
6
V
Continuous phase node pin voltage (OUT1, OUT2)
–0.7
VM + 0.7
V
1
V
Current sense input pin voltage (ISEN)
(2)
–0.5
Output current (100% duty cycle)
3.5
A
Operating junction temperature, TJ
–40
150
°C
Storage temperature, Tstg
–65
150
°C
(1)
(2)
Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings
only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended
Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
Transients of ±1 V for less than 25 ns are acceptable
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6.2 ESD Ratings
VALUE
Human-body model (HBM), per AEC Q100-002 (1)
Electrostatic
discharge
V(ESD)
(1)
Charged-device model (CDM), per AEC
Q100-011
UNIT
±2000
All pins
±500
Corner pins (1, 4, 5, and 8)
±750
V
AEC Q100-002 indicates that HBM stressing shall be in accordance with the ANSI/ESDA/JEDEC JS-001 specification.
6.3 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted)
MIN
NOM
MAX
UNIT
VM
Power supply voltage
6.8
45
VI
Logic input voltage (IN1, IN2)
0
5.5
fPWM
Logic input PWM frequency (IN1, IN2)
0
200 (1)
Ipeak
Peak output current (2)
0
3.6
A
TA
Operating ambient temperature
–40
125
°C
(1)
(2)
V
V
kHz
The voltages applied to the inputs should have at least 800 ns of pulse width to ensure detection. Typical devices require at least 400
ns. If the PWM frequency is 200 kHz, the usable duty cycle range is 16% to 84%
Power dissipation and thermal limits must be observed
6.4 Thermal Information
DRV8872-Q1
THERMAL METRIC
(1)
DDA (HSOP)
UNIT
8 PINS
RθJA
Junction-to-ambient thermal resistance
41.7
°C/W
RθJC(top)
Junction-to-case (top) thermal resistance
53.7
°C/W
RθJB
Junction-to-board thermal resistance
12.4
°C/W
ψJT
Junction-to-top characterization parameter
3
°C/W
ψJB
Junction-to-board characterization parameter
12.6
°C/W
RθJC(bot)
Junction-to-case (bottom) thermal resistance
2.6
°C/W
(1)
4
For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application
report (SPRA953).
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6.5 Electrical Characteristics
Over recommended operating conditions unless otherwise noted. Typical limits apply for TA = 25°C and VVM = 24 V
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
POWER SUPPLY (VM)
VVM
VM operating voltage
IVM
VM operating supply current
IVMSLEEP
VM sleep current
tON
Turnon time
(1)
6.8
3
VM = 12 V
VM > VUVLO with IN1 or IN2 high
40
45
V
10
mA
13
µA
50
µs
0.5
V
LOGIC-LEVEL INPUTS (IN1, IN2)
VIL
Input logic low voltage
VIH
Input logic high voltage
VHYS
Input logic hysteresis
IIL
Input logic low current
VIN = 0 V
IIH
Input logic high current
VIN = 3.3 V
RPD
Pulldown resistance
To GND
100
tPD
Propagation delay
INx to OUTx change (see Figure 6)
0.7
1
μs
tsleep
Time to sleep
Inputs low to sleep
1
1.5
ms
1.6
V
0.5
–1
V
1
33
μA
100
μA
kΩ
MOTOR DRIVER OUTPUTS (OUT1, OUT2)
RDS(ON)
High-side FET on resistance
VM = 24 V, I = 1 A, fPWM = 25 kHz
307
610
mΩ
RDS(ON)
Low-side FET on resistance
VM = 24 V, I = 1 A, fPWM = 25 kHz
258
500
mΩ
tDEAD
Output dead time
Vd
Body diode forward voltage
250
IOUT = 1 A
ns
0.8
1
V
0.35
0.38
V
CURRENT REGULATION
VTRIP
ISEN voltage for current
chopping
tOFF
PWM off-time
tBLANK
PWM blanking time
0.32
25
μs
2
µs
PROTECTION CIRCUITS
VM falls until UVLO triggers
6.3
6.5
VM rises until operation recovers
6.4
6.7
VUVLO
VM undervoltage lockout
VUV,HYS
VM undervoltage hysteresis
IOCP
Overcurrent protection trip
level
tOCP
Overcurrent deglitch time
2
μs
tRETRY
Overcurrent retry time
3
ms
TSD
Thermal shutdown
temperature (2)
180
°C
THYS
Thermal shutdown
hysteresis (2)
40
°C
Rising to falling threshold
100
180
3.7
4.5
155
V
mV
6.6
A
nFAULT OPEN DRAIN OUTPUT
VOL
Output low voltage
IO = 5 mA
IOH
Output high leakage current
VO = 3.3 V
(1)
(2)
0.5
V
1
µA
tON applies when the device initially powers up, and when it exits sleep mode.
Ensured by design
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6.6 Typical Characteristics
0.37
1.9
1.7
0.36
1.6
1.5
V T R IP ( V )
Normalized RDS(on) / RDS(on)_25qC
1.8
1.4
1.3
1.2
0.35
1.1
0.34
1
0.9
0.8
0.7
-40
0.33
-20
0
20
40
60
80
100
Ambient Temperature (qC)
120
-40
140
-20
0
20
40
60
80
100
Temperature (°C)
D001
120
140
D003
Figure 2. VTRIP vs Temperature
Figure 1. RDS(on) vs Temperature
10
IV M S L E E P (µ A )
8
6
4
2
0
0
5
10
15
20
25
30
35
VM (V)
40
45
D004
Figure 3. IVMSLEEP vs VM at 25°C
6
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7 Detailed Description
7.1 Overview
The DRV8872-Q1 device is an optimized 8-pin device for driving brushed DC motors with 6.8 to 45 V and up to
3.6-A peak current. The integrated current regulation restricts motor current to a predefined maximum. Two logic
inputs control the H-bridge driver, which consists of four N-channel MOSFETs that have a typical Rds(on) of 565
mΩ (including one high-side and one low-side FET). A single power input, VM, serves as both device power and
the motor winding bias voltage. The integrated charge pump of the device boosts VM internally and fully
enhances the high-side FETs. Motor speed can be controlled with pulse-width modulation, at frequencies
between 0 to 200 kHz. The device has an integrated sleep mode that is entered by bringing both inputs low. An
assortment of protection features prevent the device from being damaged if a system fault occurs.
7.2 Functional Block Diagram
Power
VM
bulk
VM
VCP
Charge
Pump
0.1 µF
VM
VCP
OUT1
Gate
Driver
OCP
GND
BDC
PPAD
VCP
VM
OUT2
Gate
Driver
IN1
Core
Logic
OCP
IN2
ISEN
RSENSE
+
nFAULT
±
VTRIP
Protection Features
Overcurrent
Monitoring
Temperature
Sensor
Voltage
Monitoring
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7.3 Feature Description
7.3.1 Bridge Control
The DRV8872-Q1 output consists of four N-channel MOSFETs that are designed to drive high current. These
MOSFETs are controlled by the two logic inputs IN1 and IN2, according to Table 1.
Table 1. H-Bridge Control
IN1
IN2
OUT1
OUT2
0
0
High-Z
High-Z
DESCRIPTION
0
1
L
H
Reverse (current OUT2 → OUT1)
1
0
H
L
Forward (current OUT1 → OUT2)
1
1
L
L
Brake; low-side slow decay
Coast; H-bridge disabled to High-Z (sleep entered after 1 ms)
The inputs can be set to static voltages for 100% duty-cycle drive, or they can be pulse-width modulated (PWM)
for variable motor speed. When using PWM, switching between driving and braking typically works best. For
example, to drive a motor forward with 50% of its max RPM, IN1 = 1 and IN2 = 0 during the driving period, and
IN1 = 1 and IN2 = 1 during the other period. Alternatively, the coast mode (IN1 = 0, IN2 = 0) for fast current
decay is also available. The input pins can be powered before VM is applied.
VM
VM
1 Reverse drive
1 Forward drive
2 Slow decay (brake)
2 Slow decay (brake)
1
1
OUT1
3 High-Z (coast)
3 High-Z (coast)
OUT2
OUT1
OUT2
2
2
3
3
FORWARD
REVERSE
Figure 4. H-Bridge Current Paths
7.3.2 Sleep Mode
When IN1 and IN2 are both low for time tSLEEP (typically 1 ms), the DRV8872-Q1 device enters a low-power
sleep mode, where the outputs remain High-Z and the device uses IVMSLEEP (microamps) of current. If the device
is powered up while both inputs are low, sleep mode is immediately entered. After IN1 or IN2 are high for at least
5 µs, the device is operational 50 µs (tON) later.
7.3.3 Current Regulation
The DRV8872-Q1 device limits the output current based on the resistance of an external sense resistor on pin
ISEN, according to Equation 1.
8
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ITRIP (A)
SLIS175 – NOVEMBER 2016
VTRIP (V)
RISEN (:)
0.35 (V)
RISEN (:)
(1)
For example, if RISEN = 0.16 Ω, the DRV8872-Q1 device limits motor current to 2.2 A no matter how much load
torque is applied. For guidelines on selecting a sense resistor, see the Sense Resistor section.
When ITRIP has been reached, the device enforces slow current decay by enabling both low-side FETs, and it
does this for time tOFF (typically 25 µs).
Motor Current (A)
ITRIP
tBLANK
tDRIVE
tOFF
Figure 5. Current Regulation Time Periods
After tOFF has elapsed, the output is re-enabled according to the two inputs INx. The drive time (tDRIVE) until
reaching another ITRIP event heavily depends on the VM voltage, the back-EMF of the motor, and the inductance
of the motor.
7.3.4 Dead Time
When an output changes from driving high to driving low, or driving low to driving high, dead time is automatically
inserted to prevent shoot-through. tDEAD is the time in the middle when the output is High-Z. If the output pin is
measured during tDEAD, the voltage will depend on the direction of current. If current is leaving the pin, the
voltage is a diode drop below ground. If current is entering the pin, the voltage is a diode drop above VM. This
diode is the body diode of the high-side or low-side FET.
IN1
IN2
OUT1
tPD
tR
tDEAD
tPD
tF
tDEAD
tPD
tF
tDEAD
tPD
tR
tDEAD
OUT2
Figure 6. Propagation Delay Time
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7.3.5 Protection Circuits
The DRV8872-Q1 device is fully protected against VM undervoltage, overcurrent, and overtemperature events.
When the device is in a protected state, nFAULT is driven low. When the fault condition is removed, nFAULT
becomes a high-impedance state.
7.3.5.1 VM Undervoltage Lockout (UVLO)
If at any time the voltage on the VM pin falls below the undervoltage-lockout threshold voltage, all FETs in the Hbridge are disabled. Operation resumes when VM rises above the UVLO threshold.
7.3.5.2 Overcurrent Protection (OCP)
If the output current exceeds the OCP threshold IOCP for longer than tOCP, all FETs in the H-bridge are disabled
for a duration of tRETRY. After that, the H-bridge re-enables according to the state of the INx pins. If the
overcurrent fault is still present, the cycle repeats; otherwise normal device operation resumes.
7.3.5.3 Thermal Shutdown (TSD)
If the die temperature exceeds safe limits, all FETs in the H-bridge is disabled. After the die temperature has
fallen to a safe level, operation automatically resumes.
Table 2. Protection Functionality
FAULT
CONDITION
H-BRIDGE BECOMES
NFAULT BECOMES
RECOVERY
VM undervoltage lockout (UVLO)
VM < VUVLO
Disabled
Low
VM > VUVLO
Overcurrent (OCP)
IOUT > IOCP
Disabled
Low
tRETRY
Thermal shutdown (TSD)
TJ > 150°C
Disabled
Low
TJ < TSD - T HYS
7.4 Device Functional Modes
The DRV8872-Q1 device can be used in multiple ways to drive a brushed DC motor.
7.4.1 PWM With Current Regulation
This scheme uses all of the capabilities of the device. The ITRIP current is set above the normal operating current,
and high enough to achieve an adequate spin-up time, but low enough to constrain current to a desired level.
Motor speed is controlled by the duty cycle of one of the inputs, while the other input is static. Brake and slow
decay is typically used during the off-time.
7.4.2 PWM Without Current Regulation
If current regulation is not needed, the ISEN pin should be directly connected to the PCB ground plane. This
mode provides the highest possible peak current: up to 3.6 A for a few hundred milliseconds (depending on PCB
characteristics and the ambient temperature). If current exceeds 3.6 A, the device might reach overcurrent
protection (OCP) or over-temperature shutdown (TSD). If that occurs, the device disables and protects itself for
about 3 ms (tRETRY) and then resumes normal operation.
7.4.3 Static Inputs With Current Regulation
The IN1 and IN2 pins can be set high and low for 100% duty cycle drive, and ITRIP can be used to control the
current, speed, and torque capability of the motor.
7.4.4 VM Control
In some systems, varying VM as a means of changing motor speed is desirable. See the Motor Voltage section
for more information.
10
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8 Application and Implementation
NOTE
Information in the following applications sections is not part of the TI component
specification, and TI does not warrant its accuracy or completeness. TI’s customers are
responsible for determining suitability of components for their purposes. Customers should
validate and test their design implementation to confirm system functionality.
8.1 Application Information
The DRV8872-Q1 device is typically used to drive one brushed DC motor.
8.2 Typical Application
GND
3.3 V
OUT2
0.2 Ÿ
IN2
BDC
ISEN
DRV8872-Q1
Controller
IN1
PU
OUT1
nFAULT
VM
PPAD
+
0.1 µF
47 µF
±
6.8-V to 45-V
Power Supply
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Figure 7. Typical Connections
8.2.1 Design Requirements
Table 3 lists the design parameters.
Table 3. Design Parameters
DESIGN PARAMETER
Motor voltage
Motor RMS current
Motor startup current
REFERENCE
EXAMPLE VALUE
VM
24 V
IRMS
0.8 A
ISTART
2A
Motor current trip point
ITRIP
2.2 A
Sense resistance
RISEN
0.16 Ω
PWM frequency
fPWM
5 kHz
8.2.2 Detailed Design Procedure
8.2.2.1 Motor Voltage
The motor voltage used depends on the ratings of the motor selected and the desired RPM. A higher voltage
spins a brushed DC motor faster with the same PWM duty cycle applied to the power FETs. A higher voltage
also increases the rate of current change through the inductive motor windings.
8.2.2.2 Drive Current
The current path is through the high-side sourcing DMOS power driver, motor winding, and low-side sinking
DMOS power driver. Power dissipation losses in one source and sink DMOS power driver are shown in
Equation 2.
PD
I2 RDS(on)Source
RDS(on)Sink
(2)
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The DRV8872-Q1 device has been measured to be capable of 2-A RMS current at 25°C on standard FR-4
PCBs. The maximum RMS current varies based on the PCB design, ambient temperature, and PWM frequency.
Typically, switching the inputs at 200 kHz compared to 20 kHz causes 20% more power loss in heat.
8.2.2.3 Sense Resistor
For optimal performance, the sense resistor must have the features that follow:
• Surface-mount device
• Low inductance
• Rated for high enough power
• Placed closely to the motor driver
The power dissipated by the sense resistor equals IRMS 2 × R. For example, if peak motor current is 3 A, RMS
motor current is 1.5 A, and a 0.2-Ω sense resistor is used, the resistor dissipates 1.5 A2 × 0.2 Ω = 0.45 W. The
power quickly increases with higher current levels.
Resistors typically have a rated power within some ambient temperature range, along with a derated power curve
for high ambient temperatures. When a PCB is shared with other components generating heat, the system
designer should add margin. It is always best to measure the actual sense resistor temperature in a final system.
Because power resistors are larger and more expensive than standard resistors, multiple standard resistors can
be used in parallel, between the sense node and ground. This configuration distributes the current and heat
dissipation.
8.2.3 Application Curves
Figure 8. Current Ramp With a 2-Ω, 1 mH,
RL Load and VM = 12 V
12
Figure 9. Current Ramp With a 2-Ω, 1 mH,
RL Load and VM = 24 V
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Figure 10. Current Ramp With a 2-Ω, 1 mH,
RL Load and VM = 45 V
Figure 11. tPD
Figure 12. Current Regulation With RSENSE = 0.26 Ω
Figure 13. OCP With 24 V and Outputs Shorted Together
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9 Power Supply Recommendations
9.1 Bulk Capacitance
Having appropriate local bulk capacitance is an important factor in motor drive system design. More bulk
capacitance is generally beneficial but with the disadvantages of increased cost and physical size.
The amount of local capacitance needed depends on a variety of factors, including:
• The highest current required by the motor system
• The power supply’s capacitance and ability to source current
• The amount of parasitic inductance between the power supply and motor system
• The acceptable voltage ripple
• The type of motor used (brushed DC, brushless DC, stepper)
• The motor braking method
The inductance between the power supply and motor drive system limits the rate that the current can change
from the power supply. If the local bulk capacitance is too small, the system responds to excessive current
demands or dumps from the motor with a change in voltage. When adequate bulk capacitance is used, the motor
voltage remains stable and high current can be quickly supplied.
The data sheet generally provides a recommended value, but system-level testing is required to determine the
appropriate sized bulk capacitor.
Power Supply
Parasitic Wire
Inductance
Motor Drive System
VBB
+
±
+
Motor
Driver
GND
Local
Bulk Capacitor
IC Bypass
Capacitor
Figure 14. Example Setup of Motor Drive System With External Power Supply
The voltage rating for bulk capacitors should be higher than the operating voltage, to provide margin for cases
when the motor transfers energy to the supply.
14
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10 Layout
10.1 Layout Guidelines
The bulk capacitor should be placed to minimize the distance of the high-current path through the motor driver
device. The connecting metal trace widths should be as wide as possible, and numerous vias should be used
when connecting PCB layers. These practices minimize inductance and allow the bulk capacitor to deliver high
current.
Small-value capacitors should be ceramic, and placed closely to device pins.
The high-current device outputs should use wide metal traces.
The device thermal pad should be soldered to the PCB top-layer ground plane. Multiple vias should be used to
connect to a large bottom-layer ground plane. The use of large metal planes and multiple vias help dissipate the
I2 × RDS(on) heat that is generated in the device.
Figure 15 shows the recommended layout and component placement.
10.2 Layout Example
GND
OUT2
IN2
ISEN
IN1
OUT1
nFAULT
VM
+
Figure 15. Layout Recommendation
10.3
Thermal Considerations
The DRV8872-Q1 device has thermal shutdown (TSD) as described in the Thermal Shutdown (TSD) section. If
the die temperature exceeds approximately 175°C, the device is disabled until the temperature drops below the
temperature hysteresis level.
Any tendency of the device to enter TSD is an indication of either excessive power dissipation, insufficient
heatsinking, or too high of an ambient temperature.
10.4 Power Dissipation
Power dissipation in the DRV8872-Q1 device is dominated by the power dissipated in the output FET resistance,
RDS(on). Use Equation 2 from the Drive Current section to calculate the estimated average power dissipation of
when driving a load.
Note that at startup, the output current is much higher than normal running current; this peak current and its
duration must be also be considered.
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Power Dissipation (continued)
The maximum amount of power that can be dissipated in the device is dependent on ambient temperature and
heatsinking.
NOTE
RDS(on) increases with temperature, so as the device heats, the power dissipation
increases. This fact must be taken into consideration when sizing the heatsink.
The power dissipation of the DRV8872-Q1 is a function of RMS motor current and the FET resistance (RDS(ON))
of each output.
Power | IRMS2 u High-side RDS(ON)
Low-side RDS(ON)
(3)
For this example, the ambient temperature is 58°C, and the junction temperature reaches 80°C. At 58°C, the
sum of RDS(ON) is about 0.72 Ω. With an example motor current of 0.8 A, the dissipated power in the form of heat
is 0.8 A2 × 0.72 Ω = 0.46 W.
The temperature that the DRV8872-Q1 reaches depends on the thermal resistance to the air and PCB. Soldering
the device PowerPAD to the PCB ground plane, with vias to the top and bottom board layers, is important to
dissipate heat into the PCB and reduce the device temperature. In the example used here, the DRV8872-Q1 had
an effective thermal resistance RθJA of 48°C/W, and a TJ value as shown in Equation 4.
TJ TA (PD u RTJA ) 58qC (0.46 W u 48qC/W ) 80qC
(4)
10.4.1 Heatsinking
The PowerPAD package uses an exposed pad to remove heat from the device. For proper operation, this pad
must be thermally connected to copper on the PCB to dissipate heat. On a multi-layer PCB with a ground plane,
this connection can be accomplished by adding a number of vias to connect the thermal pad to the ground plane.
On PCBs without internal planes, a copper area can be added on either side of the PCB to dissipate heat. If the
copper area is on the opposite side of the PCB from the device, thermal vias are used to transfer the heat
between top and bottom layers.
For details about how to design the PCB, refer to the TI application report, PowerPAD™ Thermally Enhanced
Package (SLMA002), and the TI application brief, PowerPAD Made Easy™ (SLMA004), available at www.ti.com.
In general, the more copper area that can be provided, the more power can be dissipated.
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11 Device and Documentation Support
11.1 Documentation Support
11.1.1 Related Documentation
For related documentation, see the following:
• Current Recirculation and Decay Modes (SLVA321)
• Calculating Motor Driver Power Dissipation (SLVA504)
• Operating an Engine-Grille Shutter Motor With DRV8872-Q1 (SLVA858)
• PowerPAD™ Thermally Enhanced Package (SLMA002)
• PowerPAD™ Made Easy (SLMA004)
• Understanding Motor Driver Current Ratings (SLVA505)
11.2 Receiving Notification of Documentation Updates
To receive notification of documentation updates, navigate to the device product folder on ti.com. In the upper
right corner, click on Alert me to register and receive a weekly digest of any product information that has
changed. For change details, review the revision history included in any revised document.
11.3 Community Resources
The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective
contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of
Use.
TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration
among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help
solve problems with fellow engineers.
Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and
contact information for technical support.
11.4 Trademarks
PowerPAD, E2E are trademarks of Texas Instruments.
All other trademarks are the property of their respective owners.
11.5 Electrostatic Discharge Caution
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more
susceptible to damage because very small parametric changes could cause the device not to meet its published specifications.
11.6 Glossary
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
12 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the most
current data available for the designated devices. This data is subject to change without notice and revision of
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.
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PACKAGE OPTION ADDENDUM
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10-Dec-2020
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
(4/5)
(6)
DRV8872DDARQ1
ACTIVE SO PowerPAD
DDA
8
2500
RoHS & Green
NIPDAUAG
Level-3-260C-168 HR
-40 to 125
8872Q
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of
