The AP1603 is a high efficiency step-up DC/DC
converter for applications using 1 to 2 NiMH battery
cells. Only three external components are required
to deliver a fixed output voltage of 3.3V. The
AP1603 starts up from less than 0.9V input with
1mA load. Pulse Frequency Modulation scheme
brings optimized performance for applications with
light output loading and low input voltages. The
output ripple and noise are lower compared with the
circuits operating in PSM mode.
The PFM control circuit operating in 150KHz (max.)
switching rate results in smaller passive
components. The space saving SOT23-6 packages
make the AP1603 an ideal choice of DC/DC
converter for space conscious applications, like
pagers, electronic cameras, and wireless microphones.