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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 useradjustable peak startup motor currents and requires minimal external components. A separate voltage-sense input (SNS) reduces current sensing errors due to parasitic trace resistance. The MAX14870/MAX14872 features shoot-through protection 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 3.3V VDD 3.3V M1 M2
M
MAX14870 MAX14872
FAULT DIR+ PWM+ EN DRIVER DRIVER VDD VDD
IRQ µC GPO PWM
CURRENT REGULATION SNS COM GND
RSENSE + THESE PIN NAMES ARE FOR THE MAX14870. ON THE MAX14872, THESE ARE THE FWD AND REV INPUTS.
19-7062; Rev 0; 9/14
MAX14870/MAX14872
Compact 4.5V to 36V Full-Bridge DC Motor Drivers
Absolute Maximum Ratings
(All voltages referenced to GND) VDD.........................................................................-0.3V to +40V M1, M2........................................................ -0.3V to (VDD+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 ...............