AN938 Datasheet, PDF (17/33 Pages) STMicroelectronics – The L4973 family is a 3.5 A monolithic DC-DC converter

AN938
3
Typical application
Typical application
Figure 22 shows the schematic of the L4973 demonstration board.
The selection of the external components allows the device to operate in the entire input
voltage range 8 V < V_IN < 55 V. The output voltage is limited by the voltage rating of the
output capacitor so it can be adjusted in the range 3.3 V < V_OUT < 30 V through the voltage
divider R3, R4. The input and output capacitors are able to sustain the RMS current in the
operating range.
3.1
Electrical specification
● Input voltage range: 8 V - 55 V
● Output voltage: 5.1 V ±3% (line, load and thermal)
● Output ripple: 51 mV
● Output current range: 1 mA - 3.5 A
● Max output ripple current: 30% Iomax
● Current limit: 4.5 A
● Switching frequency: 150 kHz.
Figure 22. Application circuit
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Doc ID 5410 Rev 10
17/33