DRV8426E
DRV8426E
SLOSE56A – MAY 2020 – REVISED OCTOBER
2020
SLOSE56A – MAY 2020 – REVISED OCTOBER 2020
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DRV8426E/P Dual H-Bridge Motor Drivers With Integrated Current Sense and Smart
Tune Technology
1 Features
•
•
•
•
•
•
•
Dual H-bridge motor driver
– One bipolar stepper motor
– Dual bidirectional brushed-DC motors
– Four unidirectional brushed-DC motors
Integrated current sense functionality
– No sense resistors required
– ±5% Full-scale current accuracy
4.5- to 33-V Operating supply voltage range
Multiple control interface options
– PHASE/ENABLE (PH/EN)
– PWM (IN/IN)
Smart tune, fast and mixed decay options
Low RDS(ON): 900 mΩ HS + LS at 24 V, 25°C
High Current Capacity Per Bridge
– 2.5-A peak (brushed), 1.5-A Full-Scale
(stepper)
Pin to pin compatible with -
•
•
•
•
•
•
•
– DRV8424E/P: 33-V, 330 mΩ HS + LS
– DRV8436E/P: 48-V, 900 mΩ HS + LS
– DRV8434E/P: 48-V, 330 mΩ HS + LS
Configurable Off-Time PWM Chopping
– 7, 16, 24 or 32 μs
Supports 1.8-V, 3.3-V, 5.0-V logic inputs
Low-current sleep mode (2 µA)
Spread spectrum clocking for low electromagnetic
interference (EMI)
Inrush current limiting in brushed-DC applications
Small package and footprint
Protection features
– VM undervoltage lockout (UVLO)
– Charge pump undervoltage (CPUV)
– Overcurrent protection (OCP)
– Thermal shutdown (OTSD)
– Fault condition output (nFAULT)
•
•
•
•
•
ATMs, currency counters, and EPOS
Office and home automation
Factory automation and robotics
Major and small home appliances
Vacuum, humanoid, and toy robotics
3 Description
The DRV8426E/P devices are dual H-bridge motor
drivers for a wide variety of industrial applications.
The devices can be used for driving two DC motors,
or a bipolar stepper motor.
The output stage of the driver consists of N-channel
power MOSFETs configured as two full H-bridges,
charge pump regulator, current sensing and
regulation, and protection circuitry. The integrated
current sensing uses an internal current mirror
architecture, removing the need for a large power
shunt resistor, saving board area and reducing system
cost. A low-power sleep mode is provided to achieve
ultra- low quiescent current draw by shutting down
most of the internal circuitry. Internal protection
features are provided for supply undervoltage lockout
(UVLO), charge pump undervoltage (CPUV), output
overcurrent (OCP), and device overtemperature
(TSD).
The DRV8426E/P is capable of driving a stepper
motor with up to 1.5-A full scale or brushed motors
with up to 2.5-A peak (dependent on PCB design).
Device Information (1)
PART NUMBER
PACKAGE
BODY SIZE (NOM)
DRV8426EPWPR
HTSSOP (28)
9.7mm x 4.4mm
DRV8426ERGER
VQFN (24)
4.0mm x 4.0mm
DRV8426PPWPR
HTSSOP (28)
9.7mm x 4.4mm
DRV8426PRGER
VQFN (24)
4.0mm x 4.0mm
(1)
For all available packages, see the orderable addendum at
the end of the data sheet.
2 Applications
•
Printers and scanners
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
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Instruments
Incorporated
intellectual
property
matters
and other important disclaimers. PRODUCTION DATA.
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DRV8426E Simplified Schematic
2
DRV8426P Simplified Schematic
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Table of Contents
1 Features............................................................................1
2 Applications..................................................................... 1
3 Description.......................................................................1
4 Revision History.............................................................. 3
5 Pin Configuration and Functions...................................4
Pin Functions.................................................................... 5
6 Specifications.................................................................. 7
6.1 Absolute Maximum Ratings........................................ 7
6.2 ESD Ratings............................................................... 7
6.3 Recommended Operating Conditions.........................8
6.4 Thermal Information....................................................8
6.5 Electrical Characteristics.............................................9
7 Detailed Description...................................................... 11
7.1 Overview................................................................... 11
7.2 Functional Block Diagrams....................................... 12
7.3 Feature Description...................................................14
7.4 Device Functional Modes..........................................25
8 Application and Implementation.................................. 27
8.1 Application Information............................................. 27
8.2 Typical Application.................................................... 27
8.3 Alternate Application................................................. 31
9 Power Supply Recommendations................................33
9.1 Bulk Capacitance...................................................... 33
10 Layout...........................................................................34
10.1 Layout Guidelines................................................... 34
11 Device and Documentation Support..........................36
11.1 Documentation Support.......................................... 36
11.2 Related Links.......................................................... 36
11.3 Receiving Notification of Documentation Updates.. 36
11.4 Community Resources............................................36
11.5 Trademarks............................................................. 36
12 Mechanical, Packaging, and Orderable
Information.................................................................... 37
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision * (May 2020) to Revision A (October 2020)
Page
• Changed Device Status to "Production Data".....................................................................................................1
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5 Pin Configuration and Functions
Figure 5-1. PWP PowerPAD™ Package 28-Pin HTSSOP Top View DRV8426E
Figure 5-2. RGE Package 24-Pin VQFN with Exposed Thermal PAD Top View DRV8426E
Figure 5-3. PWP PowerPAD™ Package 28-Pin HTSSOP Top View DRV8426P
4
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Figure 5-4. RGE Package 24-Pin VQFN with Exposed Thermal PAD Top View DRV8426P
Pin Functions
PIN
NAME
PWP
RGE
TYPE
DESCRIPTION
DRV8426E
DRV8426P
DRV8426E
DRV8426P
ADECAY
21
21
16
16
I
Decay mode setting pin. Set the decay
mode for bridge A; quad-level pin.
AEN
25
—
20
—
I
Bridge A enable input. Logic high
enables bridge A; logic low disables the
bridge Hi-Z.
AIN1
—
25
—
20
I
Bridge A PWM input. Logic controls the
state of H-bridge A; internal pulldown.
AIN2
—
24
—
19
I
Bridge B PWM input. Logic controls the
state of H-bridge B; internal pulldown.
AOUT1
4, 5
4, 5
3
3
O
Winding A output. Connect to motor
winding.
AOUT2
6, 7
6, 7
4
4
O
Winding A output. Connect to motor
winding.
APH
24
—
19
—
I
Bridge A phase input. Logic high drives
current from AOUT1 to AOUT2.
VREFA
18
18
13
13
I
Reference voltage input. Voltage on this
pin sets the full scale chopping current in
H-bridge A.
BDECAY
20
20
15
15
I
Decay mode setting pin. Set the decay
mode for bridge B; quad-level pin.
BEN
23
—
18
—
I
Bridge B enable input. Logic high
enables bridge B; logic low disables the
bridge Hi-Z.
BIN1
—
23
—
18
I
Bridge B PWM input. Logic controls the
state of H-bridge B; internal pulldown.
BIN2
—
22
—
17
I
Bridge B PWM input. Logic controls the
state of H-bridge B; internal pulldown.
BOUT1
10, 11
10, 11
6
6
O
Winding B output. Connect to motor
winding.
BOUT2
8, 9
8, 9
5
5
O
Winding B output. Connect to motor
winding.
BPH
22
—
17
—
I
Bridge B phase input. Logic high drives
current from BOUT1 to BOUT2.
VREFB
17
17
12
12
I
Reference voltage input. Voltage on this
pin sets the full scale chopping current in
H-bridge B.
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PIN
NAME
CPH
RGE
DRV8426E
DRV8426P
DRV8426E
DRV8426P
28
28
23
23
CPL
27
27
22
22
GND
14
14
9
9
TYPE
DESCRIPTION
PWR
Charge pump switching node. Connect a
X7R, 0.022-μF, VM-rated ceramic
capacitor from CPH to CPL.
PWR
Device ground. Connect to system
ground.
TOFF
19
19
14
14
I
DVDD
15
15
10
10
PWR
VCP
1
1
24
24
O
Sets the decay mode off-time during
current chopping; quad-level pin. Also
sets the ripple current in smart tune ripple
control mode.
Logic supply voltage. Connect a X7R,
0.47-μF to 1-μF, 6.3-V or 10-V rated
ceramic capacitor to GND.
Charge pump output. Connect a X7R,
0.22-μF, 16-V ceramic capacitor to VM.
VM
2, 13
2, 13
1, 8
1, 8
PWR
Power supply. Connect to motor supply
voltage and bypass to PGND with two
0.01-μF ceramic capacitors (one for each
pin) plus a bulk capacitor rated for VM.
PGND
3, 12
3, 12
2, 7
2, 7
PWR
Power ground. Connect to system
ground.
16
16
11
11
O
Fault indication. Pulled logic low with fault
condition; open-drain output requires an
external pullup resistor.
nFAULT
nSLEEP
PAD
6
PWP
26
26
21
21
I
Sleep mode input. Logic high to enable
device; logic low to enter low-power
sleep mode; internal pulldown resistor.
An nSLEEP low pulse clears faults.
-
-
-
-
-
Thermal pad. Connect to system ground.
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6 Specifications
6.1 Absolute Maximum Ratings
over operating free-air temperature range referenced with respect to GND (unless otherwise noted)
MIN
MAX
UNIT
Power supply voltage (VM)
–0.3
35
V
Charge pump voltage (VCP, CPH)
–0.3
VVM + 7
V
Charge pump negative switching pin (CPL)
–0.3
VVM
V
nSLEEP pin voltage (nSLEEP)
–0.3
VVM
V
Internal regulator voltage (DVDD)
–0.3
5.75
V
Control pin voltage (APH, AEN, BPH, BEN, AIN1, AIN2, BIN1, BIN2, nFAULT,
ADECAY, BDECAY, TOFF)
–0.3
5.75
V
Open drain output current (nFAULT)
0
10
mA
Reference input pin voltage (VREFA, VREFB)
–0.3
5.75
V
Continuous phase node pin voltage (AOUT1, AOUT2, BOUT1, BOUT2)
–1
VVM + 1
V
Transient 100 ns phase node pin voltage (AOUT1, AOUT2, BOUT1, BOUT2)
–3
VVM + 3
V
Peak drive current (AOUT1, AOUT2, BOUT1, BOUT2)
Internally Limited
A
Operating ambient temperature, TA
–40
125
°C
Operating junction temperature, TJ
–40
150
°C
Storage temperature, Tstg
–65
150
°C
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-maximumrated conditions for extended periods may affect device reliability.
6.2 ESD Ratings
VALUE
Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001
V(ESD)
Electrostatic
discharge
Charged-device model (CDM), per JEDEC specification JESD22C101
UNIT
±2000
Corner pins for PWP (1,
14, 15, and 28)
±750
Other pins
±500
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6.3 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted)
MIN
VVM
Supply voltage range for normal (DC) operation
VI
Logic level input voltage
VREF
Reference rms voltage range (VREFA, VREFB)
ƒPWM
Applied PWM signal (APH, AEN, BPH, BEN, AIN1, AIN2, BIN1, BIN2)
MAX
UNIT
4.5
33
V
0
5.5
V
0.05
3.3
V
0
100
kHz
IFS
Motor full-scale current (xOUTx)
0
1.5
A
Irms
Motor RMS current (xOUTx)
0
1.1
A
TA
Operating ambient temperature
–40
125
°C
TJ
Operating junction temperature
–40
150
°C
6.4 Thermal Information
THERMAL METRIC(1)
RθJA
8
RGE (VQFN)
28 PINS
24 PINS
UNIT
33.0
43.0
°C/W
RθJC(top) Junction-to-case (top) thermal resistance
28.0
35.0
°C/W
RθJB
Junction-to-board thermal resistance
12.9
19.9
°C/W
ψJT
Junction-to-top characterization parameter
0.7
1.0
°C/W
ψJB
Junction-to-board characterization parameter
12.8
19.8
°C/W
RθJC(bot) Junction-to-case (bottom) thermal resistance
4.9
6.7
°C/W
(1)
Junction-to-ambient thermal resistance
PWP (HTSSOP)
For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application
report.
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6.5 Electrical Characteristics
Typical values are at TA = 25°C and VVM = 24 V. All limits are over recommended operating conditions, unless otherwise
noted.
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
POWER SUPPLIES (VM, DVDD)
IVM
VM operating supply current
nSLEEP = 1, No motor load
5
6.5
mA
IVMQ
VM sleep mode supply current
nSLEEP = 0
2
4
μA
40
μs
tSLEEP
Sleep time
nSLEEP = 0 to sleep-mode
tRESET
nSLEEP reset pulse
nSLEEP low to clear fault
120
μs
20
tWAKE
Wake-up time
nSLEEP = 1 to output transition
0.8
1.2
ms
tON
Turn-on time
VM > UVLO to output transition
0.8
1.2
ms
5.25
V
VDVDD
Internal regulator voltage
No external load, 6 V < VVM < 33 V
4.75
5
No external load, VVM = 4.5 V
4.2
4.35
V
VVM + 5
V
CHARGE PUMP (VCP, CPH, CPL)
VVCP
VCP operating voltage
6 V < VVM < 33 V
f(VCP)
Charge pump switching
frequency
VVM > UVLO; nSLEEP = 1
360
kHz
LOGIC-LEVEL INPUTS (APH, AEN, BPH, BEN, AIN1, AIN2, BIN1, BIN2, nSLEEP)
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 = 5 V
tPD
Propagation delay
xPH, xEN, xINx input to current change
0
0.6
V
1.5
5.5
V
150
–1
mV
1
μA
100
μA
800
ns
QUAD-LEVEL INPUTS (ADECAY, BDECAY, TOFF)
VI1
Input logic-low voltage
Tied to GND
1
1.25
1.4
V
Input Hi-Z voltage
Hi-Z (>500kΩ to GND)
1.8
2
2.2
V
VI4
Input logic-high voltage
Tied to DVDD
2.7
IO
Output pull-up current
VI2
VI3
330kΩ ± 5% to GND
0
0.6
5.5
10
V
V
μA
CONTROL OUTPUTS (nFAULT)
VOL
Output logic-low voltage
IOH
Output logic-high leakage
IO = 5 mA
–1
0.5
V
1
μA
550
mΩ
MOTOR DRIVER OUTPUTS (AOUT1, AOUT2, BOUT1, BOUT2)
TJ = 25 °C, IO = -1 A
RDS(ONH)
RDS(ONL)
tSR
High-side FET on resistance
Low-side FET on resistance
Output slew rate
450
TJ = 125 °C, IO = -1 A
700
850
mΩ
TJ = 150 °C, IO = -1 A
780
950
mΩ
TJ = 25 °C, IO = 1 A
450
550
mΩ
TJ = 125 °C, IO = 1 A
700
850
mΩ
TJ = 150 °C, IO = 1 A
780
950
mΩ
VM = 24V, IO = 1 A, Between 10% and
90%
240
V/µs
PWM CURRENT CONTROL (VREFA, VREFB)
KV
Transimpedance gain
VREF = 3.3 V
IVREF
VREF Leakage Current
VREF = 3.3 V
2.09
2.2
2.31
V/A
8.25
μA
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Typical values are at TA = 25°C and VVM = 24 V. All limits are over recommended operating conditions, unless otherwise
noted.
PARAMETER
tOFF
PWM off-time
ΔITRIP
Current trip accuracy
IO,CH
AOUT and BOUT current
matching
TEST CONDITIONS
MIN
TYP
TOFF = 0
7
TOFF = 1
16
TOFF = Hi-Z
24
TOFF = 330 kΩ to GND
32
MAX
μs
IO = 1.5 A, 10% to 20% current setting
–15
15
IO = 1.5 A, 20% to 67% current setting
–10
10
-5
5
–2.5
2.5
IO = 1.5 A, 68% to 100% current setting
IO = 1.5 A
UNIT
%
%
PROTECTION CIRCUITS
VUVLO
VM UVLO lockout
VM falling, UVLO falling
4.1
4.25
4.35
VM rising, UVLO rising
4.2
4.35
4.45
VUVLO,HYS
Undervoltage hysteresis
Rising to falling threshold
VCPUV
Charge pump undervoltage
VCP falling
IOCP
Overcurrent protection
Current through any FET
2.5
tOCP
Overcurrent deglitch time
TOTSD
Thermal shutdown
Die temperature TJ
150
THYS_OTSD
Thermal shutdown hysteresis
Die temperature TJ
10
100
mV
VVM + 2
V
A
1.8
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V
165
20
μs
180
°C
°C
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7 Detailed Description
7.1 Overview
The DRV8426E/P are integrated motor driver solutions for bipolar stepper motors or dual brushed-DC motors.
The devices integrate two N-channel power MOSFET H-bridges, integrated current sense and regulation
circuitry. The DRV8426E/P are pin-to-pin compatible with the DRV8424E/P, DRV8436E/P, and the
DRV8434E/P. The DRV8426E/P can be powered with a supply voltage between 4.5 and 33 V. The DRV8426E/P
are capable of providing an output current up to 2.5-A peak or 1.5-A full-scale. The actual full-scale and rms
current depends on the ambient temperature, supply voltage, and PCB thermal capability.
The DRV8426E/P devices use an integrated current-sense architecture which eliminates the need for two
external power sense resistors, hence saving significant board space, BOM cost, design efforts and reduces
significant power consumption. This architecture removes the power dissipated in the sense resistors by using a
current mirror approach and using the internal power MOSFETs for current sensing. The current regulation set
point is adjusted by the voltage at the VREFA and VREFB pins.
A simple PH/EN (DRV8426E) or PWM (DRV8426P) interface allows easy interfacing to the controller circuit.
The current regulation is highly configurable, with several decay modes of operation. The decay mode can be
selected as a smart tune Dynamic Decay, smart tune Ripple Control, mixed, or fast decay. The PWM off-time, t
OFF, can be adjusted to 7, 16, 24, or 32 μs.
A low-power sleep mode is included which allows the system to save power when not driving the motor.
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7.2 Functional Block Diagrams
Figure 7-1. DRV8426E Block Diagram
12
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Figure 7-2. DRV8426P Block Diagram
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7.3 Feature Description
The following table shows the recommended values of the external components for the driver.
Figure 7-3. Resistor divider connected to the VREF pins
Table 7-1. External Components
COMPONENT
PIN 1
PIN 2
CVM1
VM
PGND
CVM2
VM
PGND
CVCP
VCP
VM
RECOMMENDED
Two X7R, 0.01-µF, VM-rated ceramic capacitors
Bulk, VM-rated capacitor
X7R, 0.22-µF, 16-V ceramic capacitor
CSW
CPH
CPL
X7R, 0.022-µF, VM-rated ceramic capacitor
CDVDD
DVDD
GND
X7R, 0.47-µF to 1-µF, 6.3-V or 10-V rated ceramic capacitor
RnFAULT
VCC
nFAULT
RREF1
VREFx
VCC
RREF2 (Optional)
VREFx
GND
>4.7-kΩ resistor
Resistor to limit chopping current. It is recommended that the value of parallel
combination of RREF1 and RREF2 should be less than 50-kΩ.
VCC is not a pin on the device, but a VCC supply voltage pullup is required for open-drain output nFAULT;
nFAULT may be pulled up to DVDD.VCC is not a pin on the DRV8932 device, but a VCC supply voltage pullup is
required for open-drain output nFAULT; nFAULT may be pulled up to DVDD.
14
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7.3.1 PWM Motor Drivers
The DRV8426E and DRV8426P contain drivers for two full H-bridges. Figure 7-4 shows a block diagram of the
circuitry.
Figure 7-4. PWM Motor Driver Block Diagram
7.3.2 Bridge Control
The DRV8426E is controlled using a PH/EN interface. Table 7-2 gives the full H-bridge state. Note that this table
does not take into account the current control built into the DRV8426E. Positive current is defined in the direction
of xOUT1 to xOUT2.
Table 7-2. DRV8426E (PH/EN) Control Interface
nSLEEP
xEN
xPH
xOUT1
xOUT2
DESCRIPTION
0
X
X
Hi-Z
Hi-Z
Sleep mode; H-bridge disabled Hi-Z
1
0
X
Hi-Z
Hi-Z
H-bridge disabled Hi-Z
1
1
0
L
H
Reverse (current xOUT2 to xOUT1)
1
1
1
H
L
Forward (current xOUT1 to xOUT2)
The DRV8426P is controlled using a PWM interface. Table 7-3 gives the full H-bridge state. Note that this table
does not take into account the current control built into the DRV8426P. Positive current is defined in the direction
of xOUT1 to xOUT2.
Table 7-3. DRV8426P (PWM) Control Interface
nSLEEP
xIN1
xIN2
xOUT1
xOUT2
DESCRIPTION
0
X
X
Hi-Z
Hi-Z
1
0
0
L
L
Sleep mode; H-bridge disabled Hi-Z
Brake; low-side slow decay
1
0
1
L
H
Reverse (current xOUT2 to xOUT1)
1
1
0
H
L
Forward (current xOUT1 to xOUT2)
1
1
1
H
H
Brake; high-side slow decay
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7.3.3 Current Regulation
The current through the motor windings is regulated by an adjustable, off-time PWM current-regulation circuit.
When an H-bridge is enabled, current rises through the winding at a rate dependent on the DC voltage,
inductance of the winding, and the magnitude of the back EMF present. When the current hits the current
regulation threshold, the bridge enters a decay mode for a period of time determined by the TOFF pin setting to
decrease the current. After the off-time expires, the bridge is re-enabled, starting another PWM cycle.
Table 7-4. Off-Time
Settings
TOFF
OFF-TIME tOFF
0
7 µs
1
16 µs
Hi-Z
24 µs
330kΩ to GND
32 µs
The TOFF pin configures the PWM OFF time for all decay modes except smart tune ripple control. The OFF time
settings can be changed on the fly. After a OFF time setting change, the new OFF time is applied after a 10 µs
de-glitch time.
The current regulation threshold is set by a comparator which monitors the voltage across the current sense
MOSFETs in parallel with the low-side power MOSFETs. To generate the reference voltage for the comparator,
the VREFx input is attenuated by a factor of Kv.
The current regulation threshold (I REG) can be calculated as I REG (A) = V REFx (V) / K V (V/A) = V REFx (V) / 2.2
(V/A).
16
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7.3.4 Decay Modes
During PWM current chopping, the H-bridge is enabled to drive through the motor winding until the PWM current
chopping threshold is reached. This is shown in Figure 7-5, Item 1.
Once the current threshold is reached, the H-bridge can operate in two different states, fast decay or slow decay.
In fast decay mode, once the current level has been reached, the H-bridge reverses state to allow winding
current to flow in a reverse direction. The opposite FETs are turned on; as the winding current approaches zero,
the bridge is disabled to prevent any reverse current flow. Fast decay mode is shown in Figure 7-5, item 2. In
slow decay mode, winding current is re-circulated by enabling both of the low-side FETs in the bridge. This is
shown in Figure 7-5, Item 3.
Figure 7-5. Decay Modes
The decay mode is selected by setting the quad-level ADECAY and BDECAY pins as shown in Table 7-5.
Table 7-5. Decay Mode Settings
xDECAY
DECAY MODE
0
Smart tune Dynamic Decay
1
Smart tune Ripple Control
Hi-Z
Mixed decay: 30% fast
330k to GND
Fast decay
The ADECAY pin sets the decay mode for H-bridge A (AOUT1, AOUT2), and the BDECAY pin sets the decay
mode for H-bridge B (BOUT1, BOUT2).
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7.3.4.1 Mixed Decay
Increasing Phase Current (A)
ITRIP
tOFF
tBLANK
tOFF
tDRIVE
Decreasing Phase Current (A)
tDRIVE
tBLANK
tDRIVE
ITRIP
tBLANK
tFAST
tDRIVE
tBLANK
tOFF
tFAST
tDRIVE
tOFF
Figure 7-6. Mixed Decay Mode
Mixed decay begins as fast decay for 30% of tOFF, followed by slow decay for the remainder of tOFF.
This mode exhibits ripple larger than slow decay, but smaller than fast decay. On decreasing current steps,
mixed decay settles to the new ITRIP level faster than slow decay.
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7.3.4.2 Fast Decay
Increasing Phase Current (A)
ITRIP
tBLANK
tOFF
tBLANK
tDRIVE
Decreasing Phase Current (A)
tDRIVE
tOFF
tBLANK
tOFF
tDRIVE
ITRIP
tBLANK
tOFF
tDRIVE
tBLANK
tOFF
tDRIVE
tBLANK
tOFF
tDRIVE
Figure 7-7. Fast/Fast Decay Mode
During fast decay, the polarity of the H-bridge is reversed. The H-bridge will be turned off as current approaches
zero in order to prevent current flow in the reverse direction.
Fast decay exhibits the highest current ripple of the decay modes for a given tOFF. Transition time on decreasing
current steps is much faster than slow decay since the current is allowed to decrease much faster.
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7.3.4.3 Smart tune Dynamic Decay
The smart tune current regulation scheme is an advanced current-regulation control method compared to
traditional fixed off-time current regulation schemes. Smart tune current regulation scheme helps the stepper
motor driver adjust the decay scheme based on operating factors such as the ones listed as follows:
•
•
•
•
•
Motor winding resistance and inductance
Motor aging effects
Motor dynamic speed and load
Motor supply voltage variation
Low-current versus high-current dI/dt
Increasing Phase Current (A)
ITRIP
tBLANK
tBLANK
tOFF
tBLANK
tOFF
tDRIVE
tDRIVE
tDRIVE
Decreasing Phase Current (A)
ITRIP
tBLANK
tOFF
tDRIVE
tBLANK
tDRIVE
tBLANK
tOFF
tFAST
tDRIVE
tFAST
Figure 7-8. Smart tune Dynamic Decay Mode
Smart tune Dynamic Decay greatly simplifies the decay mode selection by automatically configuring the decay
mode between slow, mixed, and fast decay. In mixed decay, smart tune dynamically adjusts the fast decay
percentage of the total mixed decay time. This feature eliminates motor tuning by automatically determining the
best decay setting that results in the lowest ripple for the motor.
The decay mode setting is optimized iteratively each PWM cycle. If the motor current overshoots the target trip
level, then the decay mode becomes more aggressive (add fast decay percentage) on the next cycle to prevent
regulation loss. If a long drive time must occur to reach the target trip level, the decay mode becomes less
aggressive (remove fast decay percentage) on the next cycle to operate with less ripple and more efficiently. On
falling steps, smart tune Dynamic Decay automatically switches to fast decay to reach the next step quickly.
Smart tune Dynamic Decay is optimal for applications that require minimal current ripple but want to maintain a
fixed frequency in the current regulation scheme.
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7.3.4.4 Smart tune Ripple Control
Increasing Phase Current (A)
ITRIP
IVALLEY
tBLANK
tBLANK
tOFF
tBLANK
tOFF
tDRIVE
Decreasing Phase Current (A)
tDRIVE
tBLANK
tOFF
tDRIVE
tDRIVE
ITRIP
IVALLEY
tBLANK
tOFF
tBLANK
tOFF
tDRIVE
tDRIVE
tBLANK
tOFF
tDRIVE
Figure 7-9. Smart tune Ripple Control Decay Mode
Smart tune Ripple Control operates by setting an I VALLEY level alongside the I TRIP level. When the current level
reaches ITRIP, instead of entering slow decay until the t OFF time expires, the driver enters slow decay until I VALLEY
is reached. Slow decay operates similar to mode 1 in which both low-side MOSFETs are turned on allowing the
current to recirculate. In this mode, tOFF varies depending on the current level and operating conditions.
This method allows much tighter regulation of the current level increasing motor efficiency and system
performance. Smart tune Ripple Control can be used in systems that can tolerate a variable off-time regulation
scheme to achieve small current ripple in the current regulation.
The ripple current in this decay mode is 11mA + 1% of the ITRIP at a specific microstep level.
7.3.4.5 Blanking time
After the current is enabled (start of drive phase) in an H-bridge, the current sense comparator is ignored for a
period of time (tBLANK) before enabling the current-sense circuitry. The blanking time also sets the minimum drive
time of the PWM. The blanking time is approximately 1 µs.
7.3.5 Charge Pump
A charge pump is integrated to supply a high-side N-channel MOSFET gate-drive voltage. The charge pump
requires a capacitor between the VM and VCP pins to act as the storage capacitor. Additionally a ceramic
capacitor is required between the CPH and CPL pins to act as the flying capacitor.
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Figure 7-10. Charge Pump Block Diagram
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7.3.6 Linear Voltage Regulators
A linear voltage regulator is integrated in the device. The DVDD regulator can be used to provide a reference
voltage. DVDD can supply a maximum of 2 mA load. For proper operation, bypass the DVDD pin to GND using
a ceramic capacitor.
The DVDD output is nominally 5-V. When the DVDD LDO current load exceeds 2 mA, the output voltage drops
significantly.
Figure 7-11. Linear Voltage Regulator Block Diagram
If a digital input must be tied permanently high (that is, ADECAY, BDECAY or TOFF), tying the input to the DVDD
pin instead of an external regulator is preferred. This method saves power when the VM pin is not applied or in
sleep mode: the DVDD regulator is disabled and current does not flow through the input pulldown resistors. For
reference, logic level inputs have a typical pulldown of 200 kΩ.
The nSLEEP pin cannot be tied to DVDD, else the device will never exit sleep mode.
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7.3.7 Logic and Quad-Level Pin Diagrams
Figure 7-12 gives the input structure for logic-level pins APH, AEN, BPH, BEN, AIN1, AIN2, BIN1, BIN2 and
nSLEEP:
Figure 7-12. Logic-level Input Pin Diagram
Quad-level logic pins TOFF, ADECAY, and BDECAY have the following structure as shown in Figure 7-13.
Figure 7-13. Quad-Level Input Pin Diagram
7.3.7.1 nFAULT Pin
The nFAULT pin has an open-drain output and should be pulled up to a 5-V or 3.3-V supply. When a fault is
detected, the nFAULT pin will be logic low. nFAULT pin will be high after power-up. For a 5-V pullup, the nFAULT
pin can be tied to the DVDD pin with a resistor. For a 3.3-V pullup, an external 3.3-V supply must be used.
Output
nFAULT
Figure 7-14. nFAULT Pin
7.3.8 Protection Circuits
The devices are fully protected against supply undervoltage, charge pump undervoltage, output overcurrent, and
device overtemperature events.
7.3.8.1 VM Undervoltage Lockout (UVLO)
If at any time the voltage on the VM pin falls below the UVLO-threshold voltage for the voltage supply, all the
outputs are disabled, and the nFAULT pin is driven low. The charge pump is disabled in this condition. Normal
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operation resumes (motor-driver operation and nFAULT released) when the VM undervoltage condition is
removed.
7.3.8.2 VCP Undervoltage Lockout (CPUV)
If at any time the voltage on the VCP pin falls below the CPUV voltage, all the outputs are disabled, and the
nFAULT pin is driven low. The charge pump remains active during this condition. Normal operation resumes
(motor-driver operation and nFAULT released) when the VCP undervoltage condition is removed.
7.3.8.3 Overcurrent Protection (OCP)
An analog current-limit circuit on each FET limits the current through the FET by removing the gate drive. If this
current limit persists for longer than the t OCP time, the FETs in that particular H-bridge are disabled and the
nFAULT pin is driven low. The charge pump remains active during this condition. Once the OCP condition is
removed, normal operation resumes after applying an nSLEEP reset pulse or a power cycling.
7.3.8.4 Thermal Shutdown (OTSD)
If the die temperature exceeds the thermal shutdown limit (T OTSD) all MOSFETs in the H-bridge are disabled,
and the nFAULT pin is driven low. After the junction temperature falls below the overtemperature threshold limit
minus the hysteresis (TOTSD – THYS_OTSD), normal operation resumes after applying an nSLEEP reset pulse or a
power cycling.
7.3.8.5 Fault Condition Summary
Table 7-6. Fault Condition Summary
FAULT
CONDITION
ERROR
REPORT
H-BRIDGE
CHARGE
PUMP
LOGIC
RECOVERY
VM undervoltage
(UVLO)
VM < VUVLO
nFAULT
Disabled
Disabled
Reset
(VDVDD < 3.9
V)
Automatic: VM > VUVLO
VCP undervoltage
(CPUV)
VCP < VCPUV
nFAULT
Disabled
Operating
Operating
VCP > VCPUV
Overcurrent (OCP)
IOUT > IOCP
nFAULT
Disabled
Operating
Operating
Latched
Thermal Shutdown
(OTSD)
TJ > TTSD
nFAULT
Disabled
Disabled
Operating
Latched
7.4 Device Functional Modes
7.4.1 Sleep Mode (nSLEEP = 0)
The state of the device is managed by the nSLEEP pin. When the nSLEEP pin is low, the device enters a lowpower sleep mode. In sleep mode, all the internal MOSFETs are disabled and the charge pump is disabled. The
tSLEEP time must elapse after a falling edge on the nSLEEP pin before the device enters sleep mode. The device
is brought out of sleep automatically if the nSLEEP pin is brought high. The t WAKE time must elapse before the
device is ready for inputs.
7.4.2 Operating Mode (nSLEEP = 1)
When the nSLEEP pin is high, and VM > UVLO, the device enters the active mode. The tWAKE time must elapse
before the device is ready for inputs.
7.4.3 nSLEEP Reset Pulse
A fault can be cleared through a quick nSLEEP pulse. This pulse width must be greater than 20 µs and shorter
than 40 µs. If nSLEEP is low for longer than 40 µs but less than 120 µs, the faults are cleared and the device
may or may not shutdown, as shown in the timing diagram. This reset pulse does not affect the status of the
charge pump or other functional blocks.
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Figure 7-15. nSLEEP Reset Pulse
7.4.4 Functional Modes Summary
Table 7-7 lists a summary of the functional modes.
Table 7-7. Functional Modes Summary
CONDITION
CONFIGURATI
ON
H-BRIDGE
DVDD Regulator CHARGE PUMP
Logic
Sleep mode
4.5 V < VM < 33 V
nSLEEP pin = 0
Disabled
Disbaled
Disabled
Disabled
Operating
4.5 V < VM < 33 V
nSLEEP pin = 1
Operating
Operating
Operating
Operating
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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 DRV8426E/P are used in brushed or stepper motor control.
8.2 Typical Application
In this application, the device is configured to drive bidirectional currents through two external loads (such as two
brushed DC motors) using H-bridge configuration. The H-bridge polarity and duty cycle are controlled from the
external controller to the xEN/xIN1 and xPH/xIN2 pins.
Figure 8-1. Typical Application Schematic
8.2.1 Design Requirements
Table 8-1 lists the design input parameters for system design.
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Table 8-1. Design Parameters
DESIGN PARAMETER
REFERENCE
EXAMPLE VALUE
Supply voltage
VM
24 V
Motor winding resistance
RL
3.7 Ω
Motor winding inductance
LL
6.5 mH
Switching Frequency
fPWM
40 kHz
Regulated Current for Each Motor
IREG
1A
8.2.2 Detailed Design Procedure
8.2.2.1 Current Regulation
The regulated current (I REG) is set by the VREFx analog voltage. When starting a brushed-DC motor, a large
inrush current may occur because there is no back-EMF. Current regulation will act to limit this inrush current
and prevent high current on startup. The regulated current (I REG) can be calculated as I REG (A) = V REFx (V) / K V
(V/A) = VREFx (V) / 2.2 (V/A).
8.2.2.2 Power Dissipation and Thermal Calculation
The output current and power dissipation capabilities of the device are heavily dependent on the PCB design
and external system conditions. This section provides some guidelines for calculating these values.
Total power dissipation (P TOT) for the device is composed of three main components. These are the power
MOSFET R DS(ON) (conduction) losses, the power MOSFET switching losses and the quiescent supply current
dissipation. While other factors may contribute additional power losses, these other items are typically
insignificant compared to the three main items.
PTOT = PCOND + PSW + PQ
P COND for each brushed-DC motor can be calculated from the device R DS(ON) and regulated output current (I
REG). Assuming same IREG for both brushed-DC motors,
PCOND = 2 x (IREG)2 x (RDS(ONH) + RDS(ONL))
It should be noted that R DS(ON) has a strong correlation with the device temperature. A curve showing the
normalized RDS(ON) with temperature can be found in the Typical Characteristics curves.
PCOND = 2 x (1-A)2 x (0.45-Ω + 0.45-Ω) = 1.8-W
P SW can be calculated from the nominal supply voltage (VM), regulated output current (I REG), switching
frequency (fPWM) and the device output rise (tRISE) and fall (tFALL) time specifications.
PSW = 2 x (PSW_RISE + PSW_FALL)
PSW_RISE = 0.5 x VM x IREG x tRISE x fPWM
PSW_FALL = 0.5 x VM x IREG x tFALL x fPWM
PSW_RISE = 0.5 x 24 V x 1 A x 100 ns x 40 kHz = 0.048 W
PSW_FALL = 0.5 x 24 V x 1 A x 100 ns x 40 kHz = 0.048 W
PSW = 2 x (0.048W + 0.048W) = 0.192 W
PQ can be calculated from the nominal supply voltage (VM) and the IVM current specification.
PQ = VM x IVM = 24 V x 5 mA = 0.12 W
The total power dissipation (P TOT) is calculated as the sum of conduction loss, switching loss and the quiescent
power loss.
PTOT = PCOND + PSW + PQ = 1.8-W + 0.192-W + 0.12-W = 2.112-W
For an ambient temperature of T A and total power dissipation (P TOT), the junction temperature (T J) is calculated
as
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TJ = TA + (PTOT x RθJA)
Considering a JEDEC standard 4-layer PCB, the junction-to-ambient thermal resistance (RθJA) is 33 °C/W for the
HTSSOP package and 43 °C/W for the VQFN package.
Assuming 25°C ambient temperature, the junction temperature for the HTSSOP package is calculated as TJ = 25°C + (2.112-W x 33°C/W) = 94.7 °C
The junction temperature for the VQFN package is calculated as TJ = 25°C + (2.112-W x 43°C/W) = 115.8 °C
It should be ensured that the device junction temperature is within the specified operating region.
8.2.2.2.1 Application Curves
CH3 = VM (10V/div), CH1 = nFAULT (3V/div), CH5 = nSLEEP (3V/div), CH7 = IREG (1A/div)
Figure 8-2. Device Power-up with nSLEEP
CH3 = VM (10V/div), CH1 = nFAULT (3V/div), CH5 = nSLEEP (3V/div), CH7 = IREG (1A/div)
Figure 8-3. Device Power-up with Supply Voltage (VM) Ramp
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CH1 = IN1 (3V/div), CH7 = IREG (1A/div), CH3 = AOUT1 (24V/div), CH2 = AOUT2 (24V/div)
Figure 8-4. Driver Full On Operation with Current Regulation
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8.3 Alternate Application
The following design procedure can be used to configure the DRV8424E/P and DRV8425E/P to drive a stepper
motor.
Figure 8-5. Alternate Application Schematic
8.3.1 Design Requirements
Table 8-2 gives design input parameters for system design.
Table 8-2. Design Parameters
DESIGN PARAMETER
REFERENCE
EXAMPLE VALUE
Supply voltage
VM
24 V
Motor winding resistance
RL
6 Ω/phase
Motor winding inductance
LL
4.1 mH/phase
θstep
1.8°/step
Target microstepping level
nm
1/2 step
Target motor speed
v
90 rpm
Motor Full Step Angle
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Table 8-2. Design Parameters (continued)
DESIGN PARAMETER
REFERENCE
EXAMPLE VALUE
IFS
1A
Target full-scale current
8.3.2 Detailed Design Procedure
8.3.2.1 Current Regulation
In a stepper motor, the full-scale current (IFS) is the maximum current driven through either winding. This quantity
depends on the VREFx voltage. The maximum allowable voltage on the VREFx pins is 3.3 V. DVDD can be
used to provide VREFx through a resistor divider.
IFS (A) = VREF (V) / 2.2 (V/A)
Note
The I FS current must also follow Equation 1 to avoid saturating the motor. VM is the motor supply
voltage, and RL is the motor winding resistance.
IFS (A)
VM (V)
RL (:) 2 u RDS(ON) (:)
(1)
8.3.2.2 Stepper Motor Speed
Next, the driving waveform needs to be planned. In order to command the correct speed, determine the
frequency of the input waveform.
If the target motor speed is too high, the motor will not spin. Make sure that the motor can support the target
speed.
For a desired motor speed (v), microstepping level (nm), and motor full step angle (θstep),
¦step VWHSV V
v (rpm) u 360 (q / rot)
Tstep (q / step) u nm (steps / microstep) u 60 (s / min)
θstep can be found in the stepper motor data sheet or written on the motor itself.
The frequency ƒ step gives the frequency of input change on the device. For the design parameters mentioned in
Design Parameters, ƒstep can be calculated as 600 Hz.
8.3.2.2.1 Decay Modes
The device supports several different decay modes: fast decay, mixed decay, and smart tune. The current
through the motor windings is regulated using an adjustable fixed-time-off scheme. This means that after any
drive phase, when a motor winding current has hit the current chopping threshold (I TRIP), the device will place
the winding in one of the decay modes for TOFF. After TOFF, a new drive phase starts.
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9 Power Supply Recommendations
The device is designed to operate from an input voltage supply (VM) range from 4.5 V to 33 V. A 0.01-µF
ceramic capacitor rated for VM must be placed at each VM pin as close to the device as possible. In addition, a
bulk capacitor must be included on VM.
9.1 Bulk Capacitance
Having appropriate local bulk capacitance is an important factor in motor drive system design. It is generally
beneficial to have more bulk capacitance, while the disadvantages are 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 will limit the rate current can change from the
power supply. If the local bulk capacitance is too small, the system will respond 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.
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.
Power Supply
Parasitic Wire
Inductance
Motor Drive System
VM
+
±
+
Motor
Driver
GND
Local
Bulk Capacitor
IC Bypass
Capacitor
Copyright © 2016, Texas Instruments Incorporated
Figure 9-1. Example Setup of Motor Drive System With External Power Supply
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10 Layout
10.1 Layout Guidelines
The VM pin should be bypassed to PGND using a low-ESR ceramic bypass capacitor with a recommended
value of 0.01 µF rated for VM. This capacitor should be placed as close to the VM pin as possible with a thick
trace or ground plane connection to the device PGND pin.
The VM pin must be bypassed to ground using a bulk capacitor rated for VM. This component can be an
electrolytic capacitor.
A low-ESR ceramic capacitor must be placed in between the CPL and CPH pins. A value of 0.022 µF rated for
VM is recommended. Place this component as close to the pins as possible.
A low-ESR ceramic capacitor must be placed in between the VM and VCP pins. A value of 0.22 µF rated for 16
V is recommended. Place this component as close to the pins as possible.
Bypass the DVDD pin to ground with a low-ESR ceramic capacitor. A value of 0.47 µF rated for 6.3 V is
recommended. Place this bypassing capacitor as close to the pin as possible.
The thermal PAD must be connected to system ground.
10.1.1 Layout Example
Figure 10-1. HTSSOP Layout Example
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Figure 10-2. QFN Layout Example
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11 Device and Documentation Support
11.1 Documentation Support
11.1.1 Related Documentation
For related documentation see the following:
• Texas Instruments, PowerPAD™ Thermally Enhanced Package application report
• Texas Instruments, PowerPAD™ Made Easy application report
• Texas Instruments, Current Recirculation and Decay Modes application report
• Texas Instruments, Calculating Motor Driver Power Dissipation application report
• Texas Instruments, Understanding Motor Driver Current Ratings application report
• Texas Instruments, High Resolution Microstepping Driver With the DRV88xx Series application report
11.2 Related Links
The table below lists quick access links. Categories include technical documents, support and community
resources, tools and software, and quick access to order now.
Table 11-1. Related Links
PARTS
PRODUCT FOLDER
ORDER NOW
TECHNICAL
DOCUMENTS
TOOLS &
SOFTWARE
SUPPORT &
COMMUNITY
DRV8426E
Click here
Click here
Click here
Click here
Click here
DRV8426P
Click here
Click here
Click here
Click here
Click here
11.3 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.
11.4 Community Resources
11.5 Trademarks
All other trademarks are the property of their respective owners.
36
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Copyright © 2020 Texas Instruments Incorporated
Product Folder Links: DRV8426E
DRV8426E
www.ti.com
SLOSE56A – MAY 2020 – REVISED OCTOBER 2020
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.
Submit Document Feedback
Copyright © 2020 Texas Instruments Incorporated
Product Folder Links: DRV8426E
37
DRV8426E
www.ti.com
SLOSE56A – MAY 2020 – REVISED OCTOBER 2020
PACKAGE OUTLINE
RGE0024B
VQFN - 1 mm max height
SCALE 3.000
PLASTIC QUAD FLATPACK - NO LEAD
4.1
3.9
A
B
0.5
0.3
PIN 1 INDEX AREA
4.1
3.9
0.3
0.2
DETAIL
OPTIONAL TERMINAL
TYPICAL
C
1 MAX
SEATING PLANE
0.05
0.00
0.08 C
2X 2.5
(0.2) TYP
2.45 0.1
7
SEE TERMINAL
DETAIL
12
EXPOSED
THERMAL PAD
13
6
2X
2.5
SYMM
25
18
1
20X 0.5
24
PIN 1 ID
(OPTIONAL)
0.3
0.2
0.1
C A B
0.05
24X
19
SYMM
24X
0.5
0.3
4219013/A 05/2017
NOTES:
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing
per ASME Y14.5M.
2. This drawing is subject to change without notice.
3. The package thermal pad must be soldered to the printed circuit board for thermal and mechanical performance.
www.ti.com
38
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Copyright © 2020 Texas Instruments Incorporated
Product Folder Links: DRV8426E
DRV8426E
www.ti.com
SLOSE56A – MAY 2020 – REVISED OCTOBER 2020
EXAMPLE BOARD LAYOUT
RGE0024B
VQFN - 1 mm max height
PLASTIC QUAD FLATPACK - NO LEAD
( 2.45)
SYMM
24
19
24X (0.6)
1
18
24X (0.25)
(R0.05)
TYP
25
SYMM
(3.8)
20X (0.5)
13
6
( 0.2) TYP
VIA
12
7
(0.975) TYP
(3.8)
LAND PATTERN EXAMPLE
EXPOSED METAL SHOWN
SCALE:15X
0.07 MIN
ALL AROUND
0.07 MAX
ALL AROUND
SOLDER MASK
OPENING
METAL
EXPOSED
METAL
SOLDER MASK
OPENING
EXPOSED
METAL
NON SOLDER MASK
DEFINED
(PREFERRED)
METAL UNDER
SOLDER MASK
SOLDER MASK
DEFINED
SOLDER MASK DETAILS
4219013/A 05/2017
NOTES: (continued)
4. This package is designed to be soldered to a thermal pad on the board. For more information, see Texas Instruments literature
number SLUA271 (www.ti.com/lit/slua271).
5. Vias are optional depending on application, refer to device data sheet. If any vias are implemented, refer to their locations shown
on this view. It is recommended that vias under paste be filled, plugged or tented.
www.ti.com
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Copyright © 2020 Texas Instruments Incorporated
Product Folder Links: DRV8426E
39
DRV8426E
www.ti.com
SLOSE56A – MAY 2020 – REVISED OCTOBER 2020
EXAMPLE STENCIL DESIGN
RGE0024B
VQFN - 1 mm max height
PLASTIC QUAD FLATPACK - NO LEAD
4X ( 1.08)
(0.64) TYP
24
19
24X (0.6)
1
25
18
24X (0.25)
(R0.05) TYP
(0.64)
TYP
SYMM
(3.8)
20X (0.5)
13
6
METAL
TYP
12
7
SYMM
(3.8)
SOLDER PASTE EXAMPLE
BASED ON 0.125 mm THICK STENCIL
EXPOSED PAD 25
78% PRINTED SOLDER COVERAGE BY AREA UNDER PACKAGE
SCALE:20X
4219013/A 05/2017
NOTES: (continued)
6. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate
design recommendations.
www.ti.com
40
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Copyright © 2020 Texas Instruments Incorporated
Product Folder Links: DRV8426E
DRV8426E
www.ti.com
SLOSE56A – MAY 2020 – REVISED OCTOBER 2020
PACKAGE OUTLINE
PWP0028M
TM
PowerPAD TSSOP - 1.2 mm max height
SCALE 2.000
SMALL OUTLINE PACKAGE
C
6.6
TYP
6.2
A
0.1 C
PIN 1 INDEX
AREA
SEATING
PLANE
26X 0.65
28
1
2X
9.8
9.6
NOTE 3
8.45
14
15
0.30
0.19
0.1
C A B
28X
4.5
4.3
B
SEE DETAIL A
(0.15) TYP
2X 0.82 MAX
NOTE 5
14
15
2X 0.825 MAX
NOTE 5
0.25
GAGE PLANE
1.2 MAX
4.05
3.53
THERMAL
PAD
0 -8
0.15
0.05
0.75
0.50
DETAIL A
A 20
TYPICAL
28
1
3.10
2.58
4224480/A 08/2018
PowerPAD is a trademark of Texas Instruments.
NOTES:
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing
per ASME Y14.5M.
2. This drawing is subject to change without notice.
3. This dimension does not include mold flash, protrusions, or gate burrs. Mold flash, protrusions, or gate burrs shall not
exceed 0.15 mm per side.
4. Reference JEDEC registration MO-153.
5. Features may differ or may not be present.
www.ti.com
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Copyright © 2020 Texas Instruments Incorporated
Product Folder Links: DRV8426E
41
DRV8426E
www.ti.com
SLOSE56A – MAY 2020 – REVISED OCTOBER 2020
EXAMPLE BOARD LAYOUT
PWP0028M
TM
PowerPAD TSSOP - 1.2 mm max height
SMALL OUTLINE PACKAGE
(3.4)
NOTE 9
(3.1)
METAL COVERED
BY SOLDER MASK
SYMM
28X (1.5)
1
28X (0.45)
28
SEE DETAILS
(R0.05) TYP
26X (0.65)
(4.05)
(0.6)
SYMM
(9.7)
NOTE 9
SOLDER MASK
DEFINED PAD
(1.2) TYP
( 0.2) TYP
VIA
15
14
(1.2) TYP
(5.8)
LAND PATTERN EXAMPLE
EXPOSED METAL SHOWN
SCALE: 8X
SOLDER MASK
OPENING
METAL UNDER
SOLDER MASK
METAL
SOLDER MASK
OPENING
EXPOSED METAL
EXPOSED METAL
0.05 MIN
ALL AROUND
0.05 MAX
ALL AROUND
NON-SOLDER MASK
DEFINED
(PREFERRED)
SOLDER MASK
DEFINED
SOLDER MASK DETAILS
15.000
4224480/A 08/2018
NOTES: (continued)
6. Publication IPC-7351 may have alternate designs.
7. Solder mask tolerances between and around signal pads can vary based on board fabrication site.
8. This package is designed to be soldered to a thermal pad on the board. For more information, see Texas Instruments literature
numbers SLMA002 (www.ti.com/lit/slma002) and SLMA004 (www.ti.com/lit/slma004).
9. Size of metal pad may vary due to creepage requirement.
10. Vias are optional depending on application, refer to device data sheet. It is recommended that vias under paste be filled, plugged
or tented.
www.ti.com
42
Submit Document Feedback
Copyright © 2020 Texas Instruments Incorporated
Product Folder Links: DRV8426E
DRV8426E
www.ti.com
SLOSE56A – MAY 2020 – REVISED OCTOBER 2020
EXAMPLE STENCIL DESIGN
PWP0028M
TM
PowerPAD TSSOP - 1.2 mm max height
SMALL OUTLINE PACKAGE
(3.1)
BASED ON
0.125 THICK
STENCIL
28X (1.5)
METAL COVERED
BY SOLDER MASK
1
28
28X (0.45)
(R0.05) TYP
26X (0.65)
(4.05)
BASED ON
0.125 THICK
STENCIL
SYMM
15
14
SYMM
(5.8)
SEE TABLE FOR
DIFFERENT OPENINGS
FOR OTHER STENCIL
THICKNESSES
SOLDER PASTE EXAMPLE
BASED ON 0.125 mm THICK STENCIL
SCALE: 8X
STENCIL
THICKNESS
SOLDER STENCIL
OPENING
0.1
0.125
0.15
0.175
3.47 X 4.53
3.10 X 4.05 (SHOWN)
2.83 X 3.70
2.62 X 3.42
4224480/A 08/2018
NOTES: (continued)
11. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate
design recommendations.
12. Board assembly site may have different recommendations for stencil design.
www.ti.com
Submit Document Feedback
Copyright © 2020 Texas Instruments Incorporated
Product Folder Links: DRV8426E
43
PACKAGE OPTION ADDENDUM
www.ti.com
27-Aug-2021
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)
DRV8426EPWPR
ACTIVE
HTSSOP
PWP
28
2500
RoHS & Green
NIPDAU
Level-3-260C-168 HR
-40 to 125
DRV8426E
DRV8426ERGER
ACTIVE
VQFN
RGE
24
3000
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 125
DRV
8426E
DRV8426PPWPR
ACTIVE
HTSSOP
PWP
28
2500
RoHS & Green
NIPDAU
Level-3-260C-168 HR
-40 to 125
DRV8426P
DRV8426PRGER
ACTIVE
VQFN
RGE
24
3000
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 125
DRV
8426P
(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
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