GENERAL DESCRIPTION
The H-Bridge can be PWM controlled by using three logic inputs (DIN1, DIN2, and EN). The MAX22212 features an accurate current drive regulation (CDR), which can be used to limit the start up current of a brushed DC motor or to control the phase current for stepper operation. The bridge output current is sensed by a non-dissipative integrated current sensing (ICS) and it is then compared with a user configurable setpoint (ITRIP). When the bridge current exceeds the setpoint, the device enforces the decay for a fixed OFF-time (tOFF). Four different decay methods are supported (Slow Decay, Fast Decay, and two Mixed Decay modes). The non-dissipative ICS eliminates the bulky external power resistors normally required for this function resulting in a dramatic space and power saving compared with mainstream applications based on the external sense resistor. A current proportional to the internally-sensed motor current is output to the external pins (ISENA, ISENB). By connecting an external resistor from these pins to GND, a voltage proportional to the motor current is generated.
Analog Devices
