RT7791P
PWM Controller for Programmable Power Converter (USBPD)
General Description
Features
Optimized for Adaptive Output Power
Integrated Low-Dropout Regulator (LDO)
Wide VDD Range : 10V to 40V
Adaptive Over-Current Protection
Adaptive Loop Gain Control for Loop Stability
High Efficiency
The RT7791P series is specifically designed to work
with controllers, such as the RT7202, so as to provide a
total solution for the USB PD or a programmable power
adapter. The RT7791P can achieve high efficiency,
meet safety standards, and consume less than 50mW
of power in a 5V standby condition.
The RT7791P possesses several innovations in
system control, by which the RT7791P can therefore
allow one to design a power a solution with a wide
range of output voltage. One of the innovations is by
using the DMAG pin, the RT7791P senses output
voltage to adjust loop gain for system stability, to adjust
output over-voltage protection threshold voltage for
external devices protection, and to adjust current limit
for Limited Power Source (LPS) safety requirements.
Green Mode Operation at Light Load or No
Load
Comprehensive Protection Features
Bulk-Capacitor Brown-In and Brown-Out
Protection
OTP Pin for External Over-Temperature
Protection
VDD Over-Voltage Protection
Output Over-Voltage and Under-Voltage
Protection
The RT7791P is also equipped with comprehensive
protection features, including Bulk-Capacitor brown-in
/brown-out protection, VDD over-voltage protection
Secondary Rectifier Short-Circuit Protection
Programmable Line Compensation
Others
(VDD OVP),
output
over-voltage/under-voltage
protection (Output OVP/UVP), secondary rectifier
short-circuit protection (SRSP), and external
over-temperature protection (External OTP). In case
for constant output power regulation, a resistor
connected to CS pin can be used to achieve accurate
line compensation across the universal input voltage
range. Moreover the RT7791P moreover provides
various features to protect against failures occurring at
the secondary-side component, such as the RT7202 or
a shunt regulator.
< 50mW in 5V Standby Mode for Power Saving
Driver Capability : 300mA/300mA
SmartJitterTM Technology
Applications
USB PD and Programmable Power Adapters
In applications, the RT7791P is suggested to use with
a Secondary controller RT7202 to realize a robust and
safe design, especially to prevent the potential fault
scenarios, due to the mis-connection of various devices,
cables, plugs and receptacles.
Simplified Application Circuit
Option
VBUS
L
1
2
N
GND
RT7202A
VDD
OPTO
GND
CS-
VFB
USBP
CC1
RT7791P
DMAG
OTP
CS
VIN
V2
CC1
Option
COMP
GND
VDD
4
3
(Optional)
GATE
Copyright © 2019 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
DS7791P-02 December 2019
www.richtek.com
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