XRP6142EL2-0-F Datasheet, PDF (1/17 Pages) Exar Corporation – Synchronous Step-Down Controller with DDR Memory Termination

March 2010
XRP6142
Synchronous Step-Down Controller with DDR
Memory Termination
Rev. 1.0.0
GENERAL DESCRIPTION
The XRP6142 is a synchronous step down
switching controller for over 15 Amps point-of-
loads converters and optimized to generate
and support DDR I, II and III memory
voltages requirements.
Optimized to operate from standard 3.3V and
5V rails, the XRP6142 supports conversions
down to 0.5V from an input voltage as low as
1V and can reach efficiencies of up to 96%.
Based on a constant on-time control scheme
and operating at a constant switching
frequency over the whole input voltage range,
it provides excellent load transient response
while requiring no external compensation
components. Three selectable on-time options
allow for further switching frequency, solution
footprint and efficiency optimization.
Dedicated support for DDR I, II and II
memories is also provided. The XRP6142
easily generates V_DDQ (V_DD) or V_TT voltages
while an on board buffer provides the buffered
V_TT reference voltage.
Under-voltage Lock out, short-circuit and
over-current and over-temperature protection
insure safe operations under abnormal
operating conditions.
The XRP6142 is available in a compact RoHS
compliant “green”/halogen free 16-pin QFN
package.
APPLICATIONS
• High-Power Point-of-Loads Converters
• Audio-Video Equipments
• FPGA and DSP Power Supplies
• DDR Memory Based Embedded Systems
FEATURES
• Over 15A Point-of-Load Capable
− Down to 0.5V Output Voltage Conversion
− Up to 96% Efficiency
• Wide 1.0V-5.5V Input Voltage Range
Conversions
− Single Input 3.3V and 5V rails Operations
• Constant On-Time Operations
− Constant Frequency Operations
− No External Compensation
• DDR I, II & III Termination Support
− V_DDQ/V_DD or V_TT Voltages Generation
− Buffered V_TT Ref. Voltage Generation
• Soft-Start and Enable Functions
• UVLO, Short Circuit and Over Current
Protection
• RoHS Compliant “Green”/Halogen Free
3mm x 3mm 16-Pin QFN Package
TYPICAL APPLICATION DIAGRAM
VIN
CIN
3V-5.5V
VCC
EN
VIN
GH
BST
SW
XRP6142
VREF
ILIM
REFIN
PGND
GL
CSGND
FB
AGND
Thermal
Pad
VDDQ/2
VTTREF
RLIM
Operation as DDR Supply
VDDQ
QT
L1
VOUT
ACNTL
VIN
VOUT
VTT
CFF R1
COUT
R3
SP2996B
REF EN
QB
R2
R4
GND
VREF
Figure. 1: XRP6142 as a Step-Down Converter or a DDR Supply
Exar Corporation
48720 Kato Road, Fremont CA 94538, USA
www.exar.com
Tel. [phone] – Fax. [phone]