XR76117
TM
PowerBlox 15A Synchronous
Step-Down COT Regulator
Description
FEATURES
The XR76117 is a synchronous step-down regulator combining the
controller, drivers, bootstrap diode and MOSFETs in a single package
for point-of-load supplies. The XR76117 has a load current rating
of 15A. A wide 5V to 22V input voltage range allows for single supply
operation from industry standard 5V, 12V and 19.6V rails.
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15A step-down regulator
4.5V to 5.5V low VIN operation
5V to 22V wide single input voltage
3V to 22V operation with external
5V bias
≥0.6V adjustable output voltage
Proprietary constant on-time control
No loop compensation required
Ceramic output capacitor stable
operation
With a proprietary emulated current mode constant on-time (COT)
control scheme, the XR76117 provides extremely fast line and
load transient response using ceramic output capacitors. It require
sno loop compensation, simplifying circuit implementation and
reducing overall component count. The control loop also provides
0.1% load and 0.1% line regulation and maintains constant
operating frequency. A selectable power saving mode, allows the user
to operate in discontinuous mode (DCM) at light current loads thereby
significantly increasing the converter efficiency.
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Programmable 70ns-1µs on-time
Constant 200kHz-1MHz frequency
Selectable CCM or CCM/DCM
operation
Power-good flag with low impedance when
power removed
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Precision enable
Programmable soft-start
5mm x 6mm QFN package
A host of protection features, including overcurrent, over temperature,
overvoltage, short-circuit, open feedback detect and UVLO, helps
achieve safe operation under abnormal operating conditions.
APPLICATIONS
The XR76117 is available in a RoHS compliant, green/halogen-free
space-saving 5mm x 6mm QFN package.
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Servers
Distributed power architecture
Point-of-load converters
FPGA, DSP and processor supplies
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Base stations, switches/routers
Typical Application
100
C
L1
C
V
OUT
ENABLE
600kHz
BST
98
96
94
92
90
88
86
84
82
80
78
76
74
72
70
EN
BST
SW
V
IN
VIN
R
FF
LIM
PVIN
PGOOD
VCC
SS
ILIM
R1
R2
POWER GOOD
R
FF
800kHz
XR76117
FB
FCCM
VSNS
PGND
C
IN
C
OUT
R
5.0V
3.3V
2.5V
1.8V
1.5V
1.2V
1.0V
V
OUT
R1
TON
AGND
R
ON
R2
C
C
SS
VCC
0.0
5.0
10.0
15.0
I
( )
A
OUT
Figure 1. Typical Application
Figure 2. Efficiency
REV1A
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