RT8206L Datasheet, PDF (1/27 Pages) Richtek Technology Corporation – High Efficiency, Main Power Supply Controller for Notebook Computers

®
RT8206L/M
High Efficiency, Main Power Supply Controller
for Notebook Computers
General Description
The RT8206L/M dual step-down, Switch-Mode Power-
Supply (SMPS) controller generates logic-supply voltages
in battery-powered systems. The RT8206L/M 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 (RT8206L).
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 RT8206L/M 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 RT8206L/M is available in a WQFN-32L 5x5 package.
Ordering Information
RT8206
Package Type
QW : WQFN-32L 5x5 (W-Type)
Lead Plating System
G : Green (Halogen Free and Pb Free)
Z : ECO (Ecological Element with
Halogen Free and Pb free)
L : With SECFB
M : Without SECFB
Note :
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.
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 (RT8206L)
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 4700ppm/°C R_DS(ON) Current Sensing
z Selectable PWM, DEM or Ultrasonic Mode
z Internal Soft-Start with 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
Copyright ©2012 Richtek Technology Corporation. All rights reserved.
DS8206L/M-07 June 2012
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
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