RT2910A
to 50mV. A current is generated to start charging up the
TMR pin when over current condition is detected. The
MOSFET is turned off when it reaches 1.45V.
PWM Inverting Converter
PWM inverting converter can act a current mode non-
synchronous Buck-Boost converter to generated
negative output voltage, embedded an internal P-
MOSFET. The UVLO (under-voltage lockout) function
ensures PWM converter operates correctly with
minimum VIN voltage. The VB regulator provides (V
IN
5V) voltage for circuit powered directly by VIN. Connect
a resistor from the RT pin to GND to set PWM switching
frequency between 300kHz to 800kHz. Current limit
comparator compares the CS pin voltage with 100mV
reference voltage. Connect resistor between inductor
and PGND to set peak inductor current limit threshold.
5VDET pin is VIN detection. After soft-start beginning, if
5VDET pin above 1V and SFB pin less 0.6V POK will
pull high.
If HV-Switch Over-current/Over-voltage is triggered, the
TMR pin will be charge. When V
TMR
above 0.6V. POK
will pull low immediately to turn off GATE.
At the same time, a 10A current source is charging the
FDLY capacitor. When the FDLY pin is a above 1.25V,
POK will pull high to turn on GATE again.
The PWM converter also provides Over Temperature
Protection (OTP).
Copyright © 2017 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
DS2910A-00
August 2017
www.richtek.com
5
RICHTEK [ RICHTEK TECHNOLOGY CORPORATION ]
