MAX22213

The MAX22213 provides four individually controllable 36V, 3.8A_MAX half H-bridge drivers. It can be used to drive four solenoids, two brushed DC motors, one single stepper motor, or a combination of different loads.

The power FETs have very low impedance resulting in high driving efficiency and low heat generated. The typical total R_ON (high side plus low side) is 0.25Ω (typ). Each half bridge can be individually PWM controlled by mean of two logic inputs (DIN_, EN_).

The MAX22213 integrates non-dissipative current sensing, which eliminates the bulky external power resistors normally required for this function, resulting in dramatic space and power saving compared with mainstream applications based on an external sense resistor. A current proportional to the internally-sensed load current is output to the external current-monitor pins (ISEN_). By connecting an external resistor to these pins, a voltage proportional to the motor current is generated. The voltage drop across the external resistors can be input into the controller ADC whenever the control algorithm requires the current/torque information.

The maximum output current per half H-bridge is I_MAX = 3.8A and is limited by the overcurrent protection (OCP) circuit. This current can be driven for very short transients and aims to effectively drive small capacitive loads.

The maximum RMS current per H-bridge is I_RMS = 2A assuming a 4-layer PCB at room temperature. Since this current is limited by thermal considerations, the actual maximum RMS current depends on the thermal characteristic of the application (PCB ground planes, heatsinks, forced air ventilation etc.).

In applications in which the requirement of the maximum current is less than 1.5A and high-sensing accuracy is desired, the half full-scale (HFS) logic input pin can be set high to halve the current ratings and double the low-side FET R_ON. This results in better current-monitor accuracy in the bottom end of the current range.

The MAX22213 features OCP, thermal shutdown (TSD), and undervoltage lockout (UVLO). An open-drain, active-low FAULT pin is activated every time a fault condition is detected. During TSD and UVLO events, the driver outputs are three-stated until normal operations are restored.

The MAX22213 is available into a small 5mm x 5mm, 32-pin TQFN and 4.4mm x 9.7mm, 28-pin TSSOP package.

Applications

• Stepper-Motor Driver
• Brushed DC Motor Driver
• Solenoid Driver
• Latched Valves