RT8223N Datasheet, PDF (1/23 Pages) Richtek Technology Corporation – High Efficiency, Main Power Supply Controller for Notebook Computer

RT8223N
High Efficiency, Main Power Supply Controller
for Notebook Computer
General Description
The RT8223N is a dual step-down, switch-mode power
supply controller generating logic-supply voltages in
battery-powered systems. It includes two Pulse Width
Modulation (PWM) controllers adjustable from 2V to 5.5V,
and also features fixed 5V/3.3V linear regulators. Each
linear regulator provides up to 100mA output current with
automatic linear regulator bootstrapping to the PWM
outputs. The RT8223N includes on-board power up
sequencing, a power good output, internal soft-start, and
soft-discharge output that prevents negative voltage during
shutdown.
The constant on-time PWM scheme can operate without
sense resistors and provide 100ns 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
above 25kHz. Moreover, the diode-emulation mode
maximizes efficiency for light load applications. The
RT8223N is available in a WQFN-24L 4x4 package.
Features
z Constant On-time Control with 100ns Load Step
Response
z Wide Input Voltage Range : 6V to 25V
z Dual Adjustable Outputs from 2V to 5.5V
z Fixed 3.3V and 5V LDO Output : 100mA
z 2V Reference Voltage
z Frequency Selectable via TONSEL Setting
z 4700ppm/°C R_DS(ON) Current Sensing
z Programmable Current Limit Combined with
Enable Control
z Selectable PWM, DEM, or Ultrasonic Mode
z Internal Soft-Start 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
RT8223N
Package Type
QW : WQFN-24L 4x4 (W-Type)
Lead Plating System
G : Green (Halogen Free and Pb Free)
Z : ECO (Ecological Element with
Halogen Free and Pb free)
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.
Marking Information
RT8223NGQW
11=YM
DNN
11= : Product Code
YMDNN : Date Code
RT8223NZQW
11 YM
DNN
11 : Product Code
YMDNN : Date Code
DS8223N-03 April 2011
www.richtek.com
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