The L4977A is a stepdown monolithic power switching regulator delivering 7A at a voltage variable from 5.1 to 40V.
Realized with BCD mixed technology, the device uses a DMOS output transistor to obtain very high efficiency and very fast switching times. Features of the L4977A include reset and power fail for microprocessors, feed forward line regulation, soft start, limiting current and thermal protection. The device is mounted in a 15-lead multiwatt plastic power package and requires few external components. Efficient operation at switching frequencies up to 500KHz allows reduction in the size and cost of external filter components.
- UNDER VOLTAGE LOCK OUT WITH HYSTERETIC TURN-ON
- INPUT/OUTPUT SYNC PIN
- VERY HIGH EFFICIENCY
- PWM LATCH FOR SINGLE PULSE PER PERIOD
- THERMAL SHUTDOWN
- SWITCHING FREQUENCY UP TO 500KHz
- CONTINUOUS MODE OPERATION
- RESET AND POWER FAIL FUNCTIONS
- PRECISE 5.1V ± 2% ON CHIP REFERENCE
- 7A OUTPUT CURRENT
- 0 TO 90% DUTY CYCLE RANGE
- 5.1V TO 40V OUTPUT VOLTAGE RANGE
- INTERNAL CURRENT LIMITING
- SOFT START
- INTERNAL FEED-FORWARD LINE REGULATION
RoHS Compliance Grade
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