RT8206BGQW Datasheet, PDF (1/26 Pages) Richtek Technology Corporation – High Efficiency, Main Power Supply Controllers for Notebook Computers

RT8206A/B
High Efficiency, Main Power Supply Controllers
for Notebook Computers
General Description
The RT8206A/B dual step-down, Switch Mode Power
Supply (SMPS) controller generates logic supply voltages
in battery powered systems. The RT8206A/B includes
two Pulse Width Modulation (PWM) controllers fixed at
5V/3.3V or adjustable from 2V to 5.5V. An optional external
charge pump can be monitored through SECFB
(RT8206A). This device also features a linear regulator
providing a fixed 5V output. The linear regulator provides
up to 70mA output current with automatic linear regulator
bootstrapping to the BYP input. The RT8206A/B includes
on-board power up sequencing, the power good outputs,
internal soft-start, and internal soft-discharge output that
prevents negative voltages on shutdown.
A constant on-time PWM control scheme operates without
sense resistors and provides 100ns response to load
transients while maintaining a relatively constant switching
frequency. The unique ultrasonic mode maintains the
switching frequency above 25kHz, which eliminates noise
in audio applications. Other features include Diode
Emulation Mode (DEM), which maximizes efficiency in
light load applications, and fixed frequency PWM mode,
which reduces RF interference in sensitive application.
The RT8206A/B is available in the WQFN-32L 5x5
package.
Features
z Wide Input Voltage Range 6V to 25V
z Dual Fixed 5V/3.3V Outputs or Adjustable from 2V
to 5.5V, 1.5% Accuracy
z Secondary Feedback Input Maintains Charge Pump
Voltage (RT8206A)
z Independent Enable and Power Good
z 5V Fixed LDO Output : 70mA
z 2V Reference Voltage ±1% : 50μA
z Constant ON-Time Control with 100ns Load Step
Response
z Frequency Selectable via TON Setting
z R_DS(ON) Current Sensing and Programmable Current
Limit
z Selectable PWM, DEM or Ultrasonic Mode
z Internal Soft-Start with 5 Steps Current Limiting and
Soft-Discharge
z High Efficiency Up to 97%
z 5mW Quiescent Power Dissipation
z Thermal Shutdown
z RoHS Compliant and Halogen Free
Applications
z Notebook and Sub-Notebook Computers
z 3-Cell and 4-Cell Li+ Battery-Powered Devices
Ordering Information
RT8206
Package Type
QW : WQFN-32L 5x5 (W-Type)
Lead Plating System
G : Green (Halogen Free and Pb Free)
Note :
A : With SECFB
B : Without SECFB
Richtek products are :
` RoHS compliant and compatible with the current require-
ments of IPC/JEDEC J-STD-020.
` Suitable for use in SnPb or Pb-free soldering processes.
Marking Information
RT8206AGQW
RT8206A
GQW
YMDNN
RT8206AGQW : Product Number
YMDNN : Date Code
RT8206BGQW
RT8206B
GQW
YMDNN
RT8206BGQW : Product Number
YMDNN : Date Code
DS8206A/B-06 August 2011
www.richtek.com
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