Regulated Charge Pump Delivers 50mA

Published:2012/11/9 0:07:00 Author:muriel | Keyword: Charge Pump, 50mA | From:SeekIC

The DC-DC converter circuit of Figure 1 substitutes a voltage tripler in place of the external inductor and diode normally associated with switching regulator IC1. Inverting and noninverting drivers in the MOSFET-driver chip (IC2) activate a diode/capacitor tripling network (D1-D3, C1-C3). In comparison with charge pumps based on single-polarity drivers, the buffer/inverter combination of IC2 enables this circuit to deliver more current with fewer parts.A 50kHz oscillator within IC1 produces the EXT signal (pin 6), which IC2 converts to drive signals (180° out of phase) for the tripler. The resulting charge-discharge action in the capacitors recharges C3 toward 10V every 20µs. The ferrite bead limits output ripple to about 20mVP-P for a 50mA load.



Reprinted Url Of This Article:
http://www.seekic.com/circuit_diagram/Power_Supply_Circuit/Regulated_Charge_Pump_Delivers_50mA.html

Print this Page | Comments | Reading(3)