ISL9105 is a 600mA, 1.6MHz step-down regulator that is
ideal for powering low-voltage microprocessors in handheld
devices such as PDAs and cellular phones. It is optimized
for generating low output voltages down to 0.8V. The supply
voltage range is from 2.7V to 5.5V, allowing for the use of a
single Li+ cell, three NiMH cells or a regulated 5V input. It
has a guaranteed minimum output current of 600mA.
1.6MHz pulse-width modulation (PWM) switching frequency
allows for use of small external components. It has flexible
operation mode selection of forced PWM mode and low IQ
mode with typical 25μA quiescent current for highest light
load efficiency to maximize battery life.
The ISL9105 includes a pair of low ON-resistance
P-Channel and N-Channel internal MOSFETs to maximize
efficiency and minimize external component count. 100%
duty-cycle operation allows less than 200mV dropout voltage
at 600mA output current.
The ISL9105 offers a typical 216ms Power-On-Reset (POR)
timer at power-up. The timer output can be reset by RSI.
When shutdown, ISL9105 discharges the output capacitor.
Other features include internal digital soft-start, enable for
power sequence, overcurrent protection, and thermal
shutdown.
The ISL9105 is offered in a 2mmx3mm 8 Ld DFN package
with 1mm maximum height. The complete converter
occupies less than 1cm2 area.