Simplified Block Diagram
Click any title below to view the detail page where available.
- Comprehensive IC Diagnostics Detect Both IC and H-Bridge Faults, Enhancing System Safety
- Both Channels are Fully Independent Without Any Shared Pins or Circuitry, Providing Complete Redundancy
- Resistor-Programmable Functionality Simplifies Software Development
- All nFET Operation, Including 100% Duty Cycle, Saves System Cost
- Automotive Motor Drivers
- Industrial Motor Drivers
A charge-pump regulator provides 9.8V gate drive with a 5V input supply voltage. A bootstrap capacitor is used to provide the voltage above the input battery voltage necessary to drive the high-side n-channel MOSFETs in the H-bridge. An internal top-off charge pump for the high-side drive allows DC (100% duty cycle) operation.
The device also includes programmable dead time, gate-drive slew rate, and MOSFET short-circuit threshold. The H-bridge can be driven in forward mode (clockwise), reverse mode (counterclockwise), braking mode, and coast mode. In braking mode, both the low-side MOSFETs are turned on (synchronous slow decay). In coast mode, all the MOSFETs in the H-bridge are off (asynchronous fast decay). The power MOSFETs are protected from shoot-through by a resistor-adjustable dead-time circuit.
Each channel also integrates a low-side current-sense amplifier. Used for sensing motor (H-bridge) current, the current-sense amplifier includes an overcurrent-protection circuit to limit the current in the event of motor faults.
Integrated diagnostics provide indication of undervoltage, overtemperature, H-bridge, and pin faults and can be configured to protect the power MOSFETs under most short-circuit conditions. In addition, the device supports implementation in ASIL systems by having two completely redundant H-bridge drivers in one package. The two channels are completely independent and fully redundant, with no shared pins or functions.
The MAX20082 is specified for operation over the full -40°C to +125°C ambient temperature range. The maximum junction temperature is 150°C, with thermal shutdown at 170°C (typ). The device is available in a 56-pin, 14mm × 6.1mm, TSSOP package.