EVALUATION KIT AVAILABLE
MAX14870/MAX14872
Compact 4.5V to 36V
Full-Bridge DC Motor Drivers
General Description
The MAX14870/MAX14872 motor drivers provide a small,
low-power and simple solution for driving and controlling
brushed DC motors and relays with voltages between
4.5V and 36V. Very low driver on-resistance reduces
power dissipation.
These drivers feature a charge-pump-less design for
reduced external components and low supply current.
Integrated fast-decay current regulation allows user-
adjustable peak startup motor currents and requires mini-
mal external components.
A separate voltage-sense input (SNS) reduces current
sensing errors due to parasitic trace resistance.
The MAX14870/MAX14872 features shoot-through protec-
tion and internal free-wheeling diodes that absorb inductive
motor currents. Driver outputs are short-circuit-protected
from shorts to ground, to the supply, and between M1 and
M2. An active-low
FAULT
output signals thermal overload
and overcurrents during fault conditions.
The MAX14870 has PWM and direction-control inputs,
while the MAX14872 has forward and reverse inputs for
direction control. See the
Function Tables.
The MAX14870/MAX14872 are available in a 12-pin
(3mm x 3mm) TDFN-EP package and operate over the
-40°C to +85°C temperature range.
Benefits and Features
●
Small Package Handles High Power and Reduces
Footprint Circuit Size
• Up to 2.5A Peak Motor Current
• Space-Saving TDFN-EP (3mm x 3mm) Package
• Flexible 4.5V–36V Supply Enables Longer Runtime
on Batteries
●
Low Power Consumption Runs Cooler and Longer
• 280mW (typ) Total Bridge On-Resistance
• 1mA (typ) Supply Current at 30kHz/24V
• 10µA (max) Standby Current at 12V
●
Simplified Designs Reduces Time to Market
• Charge-Pump-Less Architecture
• Current Regulation Only Requires a Sense Resistor
•
Current-Sense Input Simplifies PCB Layout
●
Integrated Protection Provides Robust Driving Solution
• Short-Circuit-Protected Drivers
• Thermal-Shutdown Undervoltage Lockout
• Diagnostic
FAULT
Output
• -40°C to +85°C Temperature Range
Applications
●
Printers and Scanners
●
Relay Drivers
●
Vending and Gaming Machines
Ordering Information
appears at end of data sheet.
Typical Application Circuit
24V
M
3.3V
V
DD
3.3V
M1
M2
MAX14870
MAX14872
FAULT
DIR
+
V
DD
V
DD
IRQ
µC
GPO
PWM
PWM
+
EN
DRIVER
DRIVER
CURRENT
REGULATION
SNS
COM
GND
R
SENSE
+ THESE PIN NAMES ARE FOR THE MAX14870. ON THE MAX14872, THESE ARE THE FWD AND REV INPUTS.
19-7062; Rev 1; 6/17
MAX14870/MAX14872
Compact 4.5V to 36V
Full-Bridge DC Motor Drivers
Absolute Maximum Ratings
(All voltages referenced to GND.)
V
DD
........................................................................-0.3V to +40V
M1, M2 ..................................................... -0.3V to (V
DD
+ 0.3V)
PWM, DIR, FWD, REV,
FAULT, EN,
SNS ..........-0.3V to +6.0V
COM .....................................................................-0.3V to +0.3V
Continuous Current Into M1, M2 ..........................................±3A
Continuous Power Dissipation (T
A
= +70°C)
Single-Layer Board (derate at 15.9mW/°C
above +70°C) ..........................................................1270mW
Multilayer Board (derate at 24.4mW/°C
above +70°C) ..........................................................1951mW
Operating Temperature Range ........................... -40°C to +85°C
Junction Temperature ...................................................... +150ºC
Storage Temperature Range .............................-65ºC to +150°C
Lead Temperature (soldering, 10s) ................................ +300°C
Solder Temperature (reflow) ...........................................+260°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these
or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect
device reliability.
Package Thermal Characteristics
(Note 1)
Junction-to-Case Thermal Resistance (θ
JC
)
TDFN-EP (Single-Layer Board) ..................................8.5°C/W
TDFN-EP (Multilayer Board).......................................8.5°C/W
Junction-to-Ambient Thermal Resistance (θ
JA
)
TDFN-EP (Single-Layer Board) ...................................63°C/W
TDFN-EP (Multilayer Board)........................................41°C/W
Note 1:
Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer
board. For detailed information on package thermal considerations, refer to
www.maximintegrated.com/thermal-tutorial.
Electrical Characteristics
PARAMETER
POWER SUPPLY
Supply Voltage
Supply Current
(V
DD
= 4.5V to 36V, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at VDD = 12V, T
A
= +25°C) (Note 2)
SYMBOL
V
DD
I
DD
EN
= low, M1/M2
not connected
EN
= high, driver
is in shutdown
V
DD
rising
CONDITIONS
MIN
4.5
f
PWM/FWD
=
50kHz
No switching
V
DD
= 12V
V
DD
= 36V
3.3
1
0.5
3.7
10
3.8
400
1.2
10
20
4.3
TYP
MAX
36
UNITS
V
mA
Shutdown Supply Current
Undervoltage Lockout
Threshold
Undervoltage Lockout
Threshold Hysteresis
I
SHDN
V
UVLO
V
UVLO_HYST
μA
V
mV
www.maximintegrated.com
Maxim Integrated
│
2
MAX14870/MAX14872
Compact 4.5V to 36V
Full-Bridge DC Motor Drivers
Electrical Characteristics (continued)
(V
DD
= 4.5V to 36V, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at VDD = 12V, T
A
= +25°C) (Note 2)
PARAMETER
DRIVER (M1, M2)
Driver Output Resistance
(High Side + Low Side)
Driver Overload Current Limit
M1, M2 Leakage Current
M1, M2 Body Diode
Forward-Voltage
R
ON
I
M_OL
I
M_LKG
EN
= High, V
M1
= V
M
2 = 0V or V
DD
Low-side diode,
EN
= high, I
F
= 2.5A
High-side diode,
EN
= high, I
F
= 2.5A
V
SNS
rising (Note 3)
V
SNS
= ±250mV
EN
= high, V
COM
= ±250mV
FWD, REV, PWM, DIR
FWD, REV, PWM, DIR
1.6
0.4
PWM, DIR, FWD, REV,
EN,
V
INPUT
= 5.5V or 0V
FAULT
asserted, I
SINK
= 5mA
FAULT
deasserted, V
FAULT
= 5.5V
Temperature rising,
FAULT
asserted
-1
+160
10
-1
+1
0.5
+1
μA
V
μA
°C
°C
94
-1
-1
2
0.8
100
I
M_
= 2.5A
T
J
= +25°C
T
J
= +125°C
3
-1
+1
1.5
1.5
280
410
395
580
mΩ
A
μA
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
V
BF
V
CURRENT REGULATION (SNS, COM)
SNS Current Sense Threshold
SNS Input Leakage Current
COM Leakage Current
V
SNS_TH
I
SNS_LKG
I
COM_LKG
V
IH
V
IL
V
EN_IH
V
EN_IL
I
IL
V
OL
I
F_LKG
T
SHDN
T
SHDN_HYST
110
+1
+1
mV
μA
μA
V
V
LOGIC SIGNALS (PWM, DIR, FWD, REV,
EN, FAULT)
Input Logic-High Voltage
Input Logic-Low Voltage
EN
Input Logic-High Voltage
EN
Input Logic-Low Voltage
Input Leakage Current
FAULT
Output Low Voltage
FAULT
Off Leakage Current
PROTECTION
Thermal-Shutdown Threshold
Thermal-Shutdown Hysteresis
www.maximintegrated.com
Maxim Integrated
│
3
MAX14870/MAX14872
Compact 4.5V to 36V
Full-Bridge DC Motor Drivers
AC Electrical Characteristics
(V
DD
= 4.5V to 36V, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at VDD = 12V, T
A
= +25°C) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MAX14870,
switching signal
applied at PWM
EN
= low
MAX14872,
switching signal
applied at FWD
or REV
140
200
R
L
= 1kΩ, C
L
= 50pF,
PWM/FWD/DIR/REV rising, Figure 1
R
L
= 1kΩ, C
L
= 50pF,
PWM/FWD/DIR/REV falling, Figure 1
PWM/FWD = high,
EN
= low,
V
SNS
> V
SNS_TH
PWM/FWD = high,
EN
= low,
V
SNS
> V
SNS_TH
M1/M2 is shorted to VDD or GND,
Figure 2
PWM/FWD = high,
EN
= low,
I
M
or I
M2
> I
M_OL
, Figure 2
PWM/FWD = high, R
L
= 1kΩ,
C
L
= 50pF,
EN
falling,
M1/M2 rising to 10%, Figure 3
PWM/FWD = high, R
L
= 1kΩ,
C
L
= 50pF,
EN
rising,
M1/M2 falling to 90%, Figure 3
7.8
620
583
15
2.5
1
2
23
22
MIN
TYP
MAX
50
kHz
50
ns
V/μs
ns
ns
μs
μs
μs
ms
μs
UNITS
PWM Frequency
f
SW
Dead Time
M1, M2 Slew Rate
M1, M2 High-Side Propagation
Delay
M1, M2 Low-Side Propagation
Delay
Current Regulation Fixed
Off-Time
Current Regulation Minimum
On-Time
Overcurrent Blanking Time
Overcurrent Autoretry Timeout
Enable Turn-On Delay
t
DEAD
SR
t
PR
t
PF
t
OFF
t
CR_BL
t
OC_BL
t
OC_TO
t
EN_ON
Enable Turn-Off Delay
t
EN_OFF
50
μs
Note 2:
All units are production tested at T
A
= +25°C. Specifications over temperature are guaranteed by design.
Note 3:
V
SNS_TH
is the threshold voltage to turn on current regulation.
www.maximintegrated.com
Maxim Integrated
│
4
MAX14870/MAX14872
Compact 4.5V to 36V
Full-Bridge DC Motor Drivers
Test Circuits/Timing Diagrams
M1/ M2
R
L
C
L
PWM/DIR
FWD/REV
V
L
0V
1V
V
DD
M1/M2
1V
t
PR
t
PF
0V
Figure 1. M1/M2 Propagation Delay
I
M1
or I
M2
I
M_OL
t
OC_BL
0A
V
L
FAULT
t
OC_TO
0V
Figure 2. Overcurrent Autoretry Timeout
www.maximintegrated.com
Maxim Integrated
│
5
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
