XR77103 Datasheet, PDF (1/28 Pages) Exar Corporation – 3-Output Programmable Buck Regulator

XR77103
Universal PMIC
3-Output Programmable Buck Regulator
Description
The XR77103 features three synchronous wide input range high
efficiency buck converters. Each converter is digitally programmable
requiring minimal external components thus providing the smallest
size solution possible.
The converters can operate in 5V, 9V, and 12V systems and have
integrated power switches. The output voltage of each converter
can be adjusted by programming the values in the V_OUT setting
registers through I²C interface. The adjustable range is 0.8 to 6V with
50mV resolution. The output voltage also can be set externally using
an external resistor divider. Output sequence among the outputs,
soft-start time and the peak inductor current limit are also set
through I²C.
The switching frequency of the converters can either be set with I²C
or can be synchronized to an external clock connected to SYNC pin
if needed. The switching regulators are designed to operate from
300kHz to 2.2MHz. Each converter operates in phase or out-of-phase
according to the value in the phase setting register. This can minimize
the input filter requirements.
XR77103 features a supervisor circuit that monitors each
converter output. PGOOD pin is asserted once sequencing is done,
all outputs are reported in regulation, and the reset timer expires.
The polarity of the signal is active high.
XR77103 also features a light load pulse skipping mode (PSM). It is
set through I²C. The PSM mode allows for a reduction on the input
power supplied to the system when the host processor is in stand-by
(low activity) mode.
FEATURES
■■ 4.5V to 14V wide input supply voltage
range
■■ Built-In MOSFET and synchronous rectifier
■■ I²C programmable supplies
Output voltage (0.8 to 6V)
Power on sequence
Soft-start timing
Switching frequency (300kHz to
2.2MHz)
Individual current limit
Optional power saving mode at light
loads
■■ Non volatile memory (NVM) with up to
10,000 times write operation
■■ 0.8V, high accuracy reference (1%)
■■ Current-mode control with simple
compensation circuit
■■ External synchronization
■■ Power good
■■ Protection
Thermal shutdown
Overvoltage transient protection
Overcurrent protection
■■ 32-pin 4mm x 4mm TQFN package
APPLICATIONS
■■ FPGA and DSP supplies
■■ Video processor supplies
■■ Applications processor power
REV1B
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