Document
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RT8230A/B/C/D/E
Dual-Channel Synchronous DC/DC Step-Down Controller with 5V/3.3V LDOs
General Description
The RT8230A/B/C/D/E is a dual-channel step-down, controller generating supply voltages for battery-powered systems. It includes two Pulse-Width Modulation (PWM) controllers adjustable from 2V to 5.5V, and two fixed 5V/ 3.3V linear regulators. Each linear regulator provides up to 100mA output current. The 5V linear regulator supplies power to the PWM drivers. The RT8230A/B/C/D/E includes on-board power-up sequencing, a power-good output, internal soft-start, and soft-discharge output that prevents negative voltage during shutdown.
A constant current ripple PWM control scheme operates without sense resistors and provides 100ns response to load transient. To eliminate noise in audio applications, an ultrasonic mode is included, which maintains the switching frequency above 25kHz. Moreover, the diodeemulation mode maximizes efficiency for light load applications. The RT8230A/B/C/D/E is available in the WQFN-20L 3x3 package.
Features
Maximum Duty Up to 96% CCRCOT Control with 100ns Load Step Response Wide Input Voltage Range : 5V to 25V Dual Adjustable Output :
CH1 : 2V to 5.5V CH2 : 2V to 4V Fixed 3.3V and 5V LDO Output : 100mA 1% Accuracy on 3.3V LDO Output Frequency Adjustable Via TON Setting 4700ppm/ °C RDS(ON) Current Sensing Adjustable Current Limit Combined with Enable Control Internal Soft-Start and Soft-Discharge Thermal Shutdown RoHS Compliant and Halogen Free
Applications
Notebook and Sub-Notebook Computers 2-Cell, 3-Cell and 4-Cell Li+ Battery-Powered Devices
Simplified Application Circuit
VOUT1
VIN
ENLDO/ENC
VIN
RT8230A/B/C/D/E VIN
UGATE2
ENLDO/ENC
BOOT2 PHASE2
UGATE1 * BOOT1
LGATE2 FB2
PHASE1
ENTRIP2
LGATE1
ENTRIP1
*
VIN
RTON
FB1 TON
LDO3
3.3V
VOUT2
ENM/SECFB * : optional
BYP1 ENM/SECFB GND
LDO5 PGOOD
5V PGOOD
Copyright ©2014 Richtek Technology Corporation. All rights reserved. DS8230A/B/C/D/E-04 February 2014
is a registered trademark of Richtek Technology Corporation.
www.richtek.com 1
RT8230A/B/C/D/E
Ordering Information
RT8230A/B/C/D/E
Package Type QW : WQFN-20L 3x3 (W-Type)
Lead Plating System G : Green
(Halogen Free and Pb Free)
Note :
Pin Function With A : ENM+ENLDO B/D : SECFB+ENLDO C/E : SECFB+ENC
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.
Pin Configurations
(TOP VIEW)
BYP1 BOOT1 UGATE1 PHASE1 LGATE1
FB1 ENTRIP1
TON ENTRIP2
FB2
20 19 18 17 16
1 15 LDO3 2 14 LDO5 3 GND 13 ENM 4 21 12 ENLDO 5 11 VIN
6 7 8 9 10
PGOOD BOOT2 UGATE2 PHASE2 LGATE2
RT8230A
BYP1 BOOT1 UGATE1 PHASE1 LGATE1
Marking Information
RT8230AGQW
2F= : Product Code
2F=YM DNN
YMDNN : Date Code
FB1 ENTRIP1
TON ENTRIP2
FB2
20 19 18 17 16
1 15 LDO3 2 14 LDO5 3 GND 13 SECFB 4 21 12 ENLDO 5 11 VIN
6 7 8 9 10
PGOOD BOOT2 UGATE2 PHASE2 LGATE2
RT8230BGQW
2E=YM DNN
2E= : Product Code YMDNN : Date Code
RT8230CGQW
2D=YM DNN
2D= : Product Code YMDNN : Date Code
RT8230DGQW
3C=YM DNN
3C= : Product Code YMDNN : Date Code
RT8230EGQW
3D=YM DNN
3D= : Product Code YMDNN : Date Code
RT8230B/D
BYP1 BOOT1 UGATE1 PHASE1 LGATE1
FB1 ENTRIP1
TON ENTRIP2
FB2
20 19 18 17 16
1 15 LDO3 2 14 LDO5 3 GND 13 SECFB 4 21 12 ENC 5 11 VIN
6 7 8 9 10
PGOOD BOOT2 UGATE2 PHASE2 LGATE2
RT8230C/E WQFN-20L 3x3
Copyright ©2014 Richtek Technology Corporation. All rights reserved. www.richtek.com 2
is a registered trademark of Richtek Technology Corporation.
DS8230A/B/C/D/E-04 February 2014
RT8230A/B/C/D/E
Functional Pin Description
Pin No.
Pin Name
Pin Function
1 FB1
Feedback Voltage Input for Channel 1. Connect FB1 to a resistive voltage divider from VOUT1 to GND to adjust output from 2V to 5.5V.
2 ENTRIP1
Enable and Current Limit Setting for Channel 1. There is an internal 5A current source to the ENTRIP1 pin. Connect a resistor to GND to set the threshold between 0.2V and 3V for channel 1 current limit. The GND PHASE1 current limit threshold is 1/10th the voltage on the ENTRIP1 pin.
3 TON
Switching Frequency Setting. Connect a resistor to GND to adjust switching frequency.
4 ENTRIP2
Enable and Current Limit Setting for Channel 2. There is an internal 5A current source to the ENTRIP2 pin. Connect a resistor to GND to set the threshold between 0.2V and 3V for channel 2 current limit. The GND PHASE2 current limit threshold is 1/10th the voltage on the ENTRIP2 pin.
5 FB2
Feedback Voltage Input for Channel 2. Connect FB2 to a resistive voltage-divider from VOUT2 to GND to adjust output from 2V to 4V.
6 PGOOD
Power Good Output for Channel 1 and Channel 2. (Logical AND)
7 BOOT2
Bootstrap Supply for Channel 2 High-Side Gate Driver. Connect to an external capacitor according to the typical application circuits.
8 UGATE2
Gate Drive Output for Channel 2 High-Side MOSFET.
9 P.