Product overview
Description
The L7981 device is a step-down switching regulator with a 3.7 A (minimum) current limited embedded Power MOSFET, so it is able to deliver up to 3 A current to the load depending on the application conditions.
The input voltage can range from 4.5 V to 28 V, while the output voltage can be set starting from 0.6 V to VIN.
Requiring a minimum set of external components, the device includes an internal 250 kHz switching frequency oscillator that can be externally adjusted up to 1 MHz.
The QFN and the HSOP packages with exposed pad allow reducing the RthJAdown to 60°C/W and 40°C/W respectively.
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All features
- 3 A DC output current
- 4.5 V to 28 V input voltage
- Output voltage adjustable from 0.6 V
- 250 kHz switching frequency, programmable up to 1 MHz
- Internal soft-start and enable
- Low dropout operation: 100% duty cycle
- Voltage feed-forward
- Zero load current operation
- Overcurrent and thermal protection
- VFQFPN 3 x 3 - 8L and HSOP8 package
Circuit Diagram
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