Chip Introduction
The SS8812T provides a dual-channel integrated motor drive solution for printers and other motor integration applications.
The SS8812T has two H-bridge drivers, each delivering a maximum output current of 1.6A (at 24V and Ta = 25°C) with proper heat dissipation, and can drive two brush DC motors, or a bipolar stepper motor, or solenoids or other inductive loads. Bipolar stepper motors can be operated in full steps, 2 subdivisions, 4 subdivisions, or high and fine points can be achieved with software. The power delivery module for each H-bridge of the SS8812T consists of N-type power MOSFETs. Each H-bridge contains a rectifier circuit and a current limiting circuit. Simple parallel digital control interface with selectable attenuation modes for fast attenuation, slow attenuation, and mixed attenuation.
The SS8812T provides a low-power sleep mode to shut down internal circuitry to achieve very low quiescent current. This sleep mode is achieved by setting the nSLEEP pin. Internal shutdown includes overcurrent protection, short-circuit protection, undervoltage lockout protection, and overtemperature protection, and provides a fault output pin nFAULT pin. The SS8812T is available in an ETSSOP28 package with exposed pads for improved heat dissipation, is lead-free, and features 100% tin-free leadframe plating.
Chip characteristics
Dual channel H-bridge current control motor driver – single or two brushed DC motors – one stepper motor
PWM control interface
Selectable current control at fixed frequency – 2 bits current control with 4 current steps
Low on-impedance metal-oxide semiconductor field-effect transistors (MOSFETs) – 24V, 1.6A maximum drive current at Ta = 25°C – 24V, RDS(on) of 720mΩ at Ta= 25°C (typical HS + LS)
8.2~36V working voltage range
Low current in sleep mode
Built-in 3.3V reference voltage
Surface mount package with heatsink
Protection Features – Overcurrent Protection (OCP) – Thermal Shutdown (TSD) – Undervoltage Lockout (UVLO) – Fault Display Pin(nFAULT)
