®
RT6257A/B
6A, 18V, 500kHz, ACOTTM Step-Down Converter
General Description
Features
4.5V to 18V Input Voltage Range
The RT6257A/B is a high-efficiency, monolithic
synchronous step-down DC-DC converter that can deliver
up to 6A output current from a 4.5V to 18V input supply.
The RT6257A/B adopts ACOT architecture to allow the
transient response to be improved and keep in constant
frequency. Cycle-by-cycle current limit provides protection
against shorted outputs and soft-start eliminates input
current surge during start-up. Fault conditions also include
output under voltage protection and thermal shutdown.
6A Output Current
Constant-On-Time Mode to Enables Fast Transient
Response
Low Output Ripple and Allows Ceramic Output
Capacitor
500kHz Switching Frequency
High Efficient Internal Power MOSFET Switch
Optimized for Lower Duty Cycle Applications
Integrated 30mΩ/20mΩ MOSFETs
Adjustable Output Voltage from 0.6V to 5V
Internal Soft-Start (1.5ms typ.)
Built-In UVP/OTP
Ordering Information
RT6257A/B
Package Type
J6F : TSOT-23-6 (FC)
Input Under Voltage Lockout
TSOT23-6 (FC) Package
Lead Plating System
G : Green (Halogen Free and Pb Free)
Applications
UVP Option
H : Hiccup
Set Top Box
Portable TV
Access Point Router
DSL Modem
LCD TV
PSM/PWM
A : PSM/PWM
B : Force-PWM
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.
Pin Configuration
(TOP VIEW)
BOOT
LX VIN
6
5
2
4
3
Marking Information
RT6257AHGJ6F
2K= : Product Code
FB EN GND
2K=DNN
DNN : Date Code
TSOT-23-6 (FC)
RT6257BHGJ6F
2J=DNN
2J= : Product Code
DNN : Date Code
Copyright 2016 Richtek Technology Corporation. All rights reserved.
©
is a registered trademark of Richtek Technology Corporation.
DS6257A/B-01 October 2016
www.richtek.com
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