RT7298B
Functional Pin Description
Pin No.
1
Pin Name
RT/SYNC
Pin Function
Oscillator resistor and external frequency synchronization input. Connecting a
resistor from this pin to GND sets the switching frequency or connecting an
external clock to this pin changes the switching frequency.
System ground. Provide the ground return path for the control circuitry and
low-side power MOSFET. The exposed pad must be soldered to a large PCB
and connected to GND for minimum power dissipation.
Power input. Supplies the power switches of the device.
Supply voltage input. Supplies the control circuitry and internal reference of the
device.
Feedback voltage input. This pin is used to set the desired output voltage via an
external resistive divider. The feedback reference voltage is 0.6V typically.
Compensation node. The current comparator threshold increases with this
control voltage. Connect external compensation elements to this pin to stabilize
the control loop.
Soft-start and tracking control input. Connect a capacitor from SS to GND to set
the soft-start period. The soft-start period can be used to track and sequence
when the external voltage on this pin overrides the internal reference.
Enable control input. Floating this pin or connecting this pin to logic high can
enable the device and connecting this pin to GND can disable the device.
Switch node. LX is the switching node that supplies power to the output and
connect the output LC filter from LX to the output load.
Bootstrap supply for high-side gate driver. Connect a 100nF or greater capacitor
from LX to BOOT to power the high-side switch.
Power good indicator output. This pin is an open-drain logic output that is pulled
to ground when the output voltage is lower or higher than its specified threshold
under the conditions of OVP, OTP, dropout, EN shutdown, or during slow start.
2, 3,
GND
15 (Exposed Pad)
4, 5
6
7
8
PVIN
VIN
FB
COMP
9
SS/TR
10
11, 12
13
EN
LX
BOOT
14
PGOOD
Copyright
©
2019 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
DS7298B-07
June 2019
www.richtek.com
3
RICHTEK [ RICHTEK TECHNOLOGY CORPORATION ]
