The RTKA210040DR0000BU demonstration board
(shown in Figure 2 and Figure 3) features the
RAA210040. Capable of delivering up to 4A of
continuous current, the RAA210040 is a compact,
synchronous step-down, non-isolated complete
power supply that is optimized for space-constrained
applications. The RAA210040 is based on a peak
current mode PWM control scheme that provides a
fast transient response and excellent loop stability.
The switching frequency is programmable from
500kHz to 4MHz with either the external resistor or
synchronization to an external clock through the
SYNC pin.
The RTKA210040DR0000BU demonstration board is
a 1×1 inch 4-layer FR4 board with 2oz. copper on all
layers. It is optimized to minimize the complete power
module solution size. Operating from a single 2.7V to
5.5V input power rail, the RTKA210040DR0000BU
demonstration board offers adjustable output voltages
down to 0.6V, up to 95% efficiency, and better than
1.5% accuracy over line, load, and temperature. A
dedicated enable pin and power-good flag allow for
easy system power rails sequencing.
By default, the board is set to a 1.2V output voltage
with a 1.2MHz switching frequency.

Features
▪ Wide input voltage range from 2.7V to 5.5V
▪ Adjustable output voltage down to 0.6V with ±1.5%
accuracy over line, load, and temperature
▪ Up to 95% conversion efficiency
▪ 100% duty cycle
▪ Internal 1ms soft-start time
▪ Prebias output start-up
▪ External frequency synchronization up to 4MHz
▪ Dedicated enable pin and PGOOD flag
▪ UVLO, overcurrent, negative overcurrent,
overvoltage, and over-temperature protections

Specifications
The demonstration board is configured and optimized
for the following operating conditions:
▪ VIN = 2.7V to 5.5V
▪ VOUT = 1.2V
▪ IOUT-MAX = 4A
▪ fSW = 1.2MHz