AN013 Datasheet, PDF (1/6 Pages) Intersil Corporation – Everything You Always Wanted to Know About the ICL8038

AN013
Optimized external driver for AIC1639
Introduction
AIC1639 is a member of AIC1638 PFM Pulse
Frequency Modulation controller IC family, for
step-up DC/DC converter featuring high efficiency
and low ripple voltage, which is exactly the same as
AIC1638 except the external driver with higher
output current comparing to the built-in edition
( AIC1638 ). The figures are shown below
The key electrical characteristics of
AIC1639
ü PFM based control
ü 75% ( Typ. ) oscillator duty cycle , 100KHz
( Typ. ) switching frequency
ü Low start up voltage
Figure 1b
Principle of step-up DC/DC converter
operation
A step-up DC/DC converter charges energy in the
inductor when the switch is on and discharges the
energy with additional energy from Input Power
Source thereto. Therefore a higher voltage output,
than input, is obtained.
The operation will be explained with reference to
the following diagrams
Figure 1a
July 2000
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