L9803 STMicroelectronics, L9803 Datasheet - Page 94

• Manufacturer Part Number: L9803
• Description: Super Smart Power Motor Driver With 8-bit Mcu, Ram, Eeprom, Adc, Wdg, Timers, Pwm And H-bridge Driver
• Manufacturer: STMicroelectronics

On-Chip Peripherals
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Main Features
The nominal current is 2A.
The low-side switch is a n-channel DMOS transistor while the high-side switch is a p-
channel DMOS transistor. Therefore no charge pump is needed.
An anti-crossconduction circuit is included: the low side DMOS is switched on only when the
high side is switched off and vice versa. This function avoid the two DMOS are switched on
together firing the high current path from battery to ground. The function is obtained by
sensing the gate voltage and therefore the delay between command and effective switch on
of the DMOS doesn’t have a fixed length.
The MCU controls all operations of the power stage through the BCSR dedicated register.
Short circuit and overtemperature conditions are reported to the CPU using dedicated error
flags.
Overtemperature and short circuit conditions switch off the bridge immediately without CPU
intervention. The function of the flags is independent of the operation mode of the bridge
(sink, source, Z).
In addition both the PWM modules can be directly connected to the power bridge. The
power bridge offers then many driving mode alternatives:
Direct Mode: the two half bridges are directly driven by IN1 and IN2 control bit in BCSR.
PWM1 Up/Down Brake Mode: the output of PWM1 drives one side of the bridge while the
other side is maintained in a fixed status.
PWM1 Symmetrical Driving Mode: PWM1 line drives directly and symmetrically both side of
the bridge.
PWM1/PWM2 Mode: PWM1 drives one side while PWM2 drives the other (two independent
half bridges).
Functional Description
A schematic description of the Power Bridge circuit is depicted in
schematic the transistors must be considered in ON condition when they gate is high (set).
Figure
45. In this
L9803