RT8243A/B/C
for Notebook Computers
The RT8243A/B/C is a dual step down, Switch Mode Power
Supply (SMPS) controller which generates logic supply
voltages for battery powered systems. It includes two
Pulse Width Modulation (PWM) controllers adjustable
regulators. One of the controllers (LDO5) provides
automatic switch over to the BYP1 input connected to
the main SMPS1 output for maximized efficiency. An
optional external charge pump can be monitored through
SECFB (RT8243B/C). Other features include on board
power up sequencing, a power good output, internal soft-
start, and a soft discharge output that prevents negative
A constant on-time PWM control scheme operates without
sense resistors and assures fast load transient response
while maintaining nearly constant switching frequency. To
eliminate noise in audio applications, an ultrasonic mode
is included, which maintains the switching frequency
maximizes efficiency for light load applications. The
from 200kHz/233kHz to 400kHz/466kHz respectively.
package, and operates over an extended temperature range
Features
2V to 5.5V Output Voltage Range
5V/3.3V Linear Regulators
Internal Current Limit Soft-Start and Soft Discharge
Built In OVP/UVP/OCP
Control (RT8243A)
(RT8243B/C)
RoHS Compliant and Halogen Free
Notebook computers
3- and 4- Cell Li+ Battery-Powered Device
RT8243A/B/C
QW : WQFN-20L 3x3 (W-Type)
Z : ECO (Ecological Element with
Pin Function With
B : SECFB
Note :
RoHS compliant and compatible with the current require-
Suitable for use in SnPb or Pb-free soldering processes.
Copyright ©2014 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
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