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RT8130B
12V High Efficiency Synchronous Buck PWM Controller
General Description
The RT8130B is a high efficiency single phase synchronous Buck DC/DC controller with 5V/12V supply voltage.
The RT8130B has embedded MOSFET gate driver with high driving capability, supporting driving voltage up to 12V for high output current application. This device uses lossless low-side MOSFET RDS(ON) current sense technique for over-current protection with adjustable threshold set by the LGATE pin (LGOCS). Other features include power good indication, enable/disable control and internal soft-start. The RT8130B also provides fault protection functions to protect the power stage output. With above functions, the IC provides customers a costeffective solution for high efficiency power conversion. The RT8130B is available in the WDFN-10L 3x3 package.
Applications
Motherboard, Memory/Chip-set Power Graphic Card, GPU/Memory Core Power Low Voltage, High Current DC/DC Regulator
Features
High Light Load Efficiency Single 5V to 12V Driver Voltage Integrated High Driving Capability N-MOSFET Gate
Drivers 300kHz Fixed Frequency Internal Oscillator 88% Maximum PWM Duty Cycle Power Good Indicator Enable/Disable Control Internal Soft-Start Lossless Low-Side MOSFET RDS(ON) Current Sensing
for Over-Current Fault Monitoring LGATE Over-Current Setting (LGOCS) OCP, UVP, OVP, OTP, UVLO
Ordering Information
RT8130B
Package Type QW : WDFN-10L 3x3 (W-Type)
Note :
Lead Plating System G : Green (Halogen Free and Pb Free)
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.
Simplified Application Circuit
VCC VPGOOD
EN
RT8130B
VCC
BOOT
UGATE
PGOOD COMP/EN
PHASE LGATE
GND
FB
VIN
VOUT
Copyright ©2016 Richtek Technology Corporation. All rights reserved. DS8130B-02 January 2016
is a registered trademark of Richtek Technology Corporation.
www.richtek.com 1
RT8130B
Pin Configurations
(TOP VIEW)
BOOT 1 PHASE 2 UGATE 3
LGATE 4 GND 5
GND
10 PGOOD 9 NC
8 FB 7 COMP/EN 11 6 VCC
WDFN-10L 3x3
Marking Information
8X=YM DNN
8X= : Product Code YMDNN : Date Code
Functional Pin Description
Pin No. 1
Pin Name BOOT
2 PHASE 3 UGATE
4 LGATE
5, 11 (Exposed Pad)
GND
Pin Function
Bootstrap Supply for High-Side Gate Driver. Connect this pin to a power source VCC through a bootstrap diode, and connect a 0.1F or greater ceramic capacitor from this pin to the PHASE pin to supply the power for high-side gate driver.
Switch Node. Connect this pin to the switching node of Buck converter. This pin is also the floating drive return of the high-side MOSFET gate driver.
High-Side MOSFET Gate Driver Output. Connect this pin to the Gate of highside MOSFET for floating drive.
Low-Side MOSFET Gate Driver Output. Connect this pin to the Gate of low-side MOSFET. This pin is also used for Over-Current Protection (OCP) threshold setting. Connect a resistor (ROCSET) from this pin to the GND pin to set the OCP threshold.
Ground. The exposed pad must be soldered to a large PCB and connected to GND for maximum power dissipation.
6
VCC
Supply Voltage Input. It is recommended to connect a 1F or greater ceramic capacitor from this pin to the GND pin. VCC also powers the low-side gate driver.
Compensation Node. Connect R-C network between this pin and the FB pin for 7 COMP/EN PWM control loop compensation. This pin is also used for enable/disable control.
Connect a small signal MOSFET to this pin to implement enable/disable control.
8 FB
Feedback Voltage Input. This pin is used for output voltage feedback input and it is also monitored for power good indication, over-voltage and under-voltage protections. Connect this pin to the converter output through voltage divider resistors for output voltage regulation.
9 NC No Internal Connection.
Power Good Indicator Output. This pin provides an open-drain output. Connect
10
PGOOD
this pin to a voltage source through a pull-up resistor. The PGOOD voltage goes high to indicate the output voltage is in regulation. This pin can be left open if the
power good indication function is not used.
Copyright ©2016 Richtek Technology Corporation. All rights reserved.
www.richtek.com 2
is a registered trademark of Richtek Technology Corporation.
DS8130B-02 January 2016
Function Block Diagram
COMP/EN
VCC
RT8130B
Regulator
BOOT
UGATE
FB -
VREF
EA +
PWM + CMP
VCC
PHASE
+ Control
IOCSET
VREF
CMP -
UV_level
+
UV
Logic OC
Current
- Sense & OCP VCC
OV_level - OV +
Comparator
LGATE
PGH_level +
GND
-
PGL_level
+
-1
PGOOD
Operation
The RT8130B is a high efficiency single-phase synchronous Buck controller with integrated MOSFET driver. The controller has a fixed frequency control, a fixed frequency 300kHz oscillator is integrated to minimize external components.
Enable The RT8130B remains in shutdown if the COMP/EN .