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6-A NON-ISOLATED DDR/QDR
FEATURES
NOMINAL SIZE =0.87 in x 0.5 in
(22,1 mm x 12,57 mm)
DESCRIPTION
VIN
Standby
GND
VTT
V
REF
Co
1
LowESR
(Required)
C
IN
(Required)
V
TT
Te
rm
inat
ion
Island
1 k
1 %
1 k
1 %
VDDQ
SSTL2
Bus
Co
2
Ceramic
(Optional)
Q1
BSS138
(Optional)
Con
hfCeramic
PTHxx050Y
(Top View)
1
5
2
3
4
6
CIN = Required Electrolytic Capacitor; 220F (3.3 ± 5 V Input), 560 F (12 V Input).
Co1 = Required Low-ESR Electrolyitic Capacitor; 470 F (3.3 ± 5 V Input), 940 F (12 V Input).
Co2 = Ceramic Capacitance for Response to a 3 A (+ 1.5 A) Load Transient; 200 F (3.3 ± 5 V Input), 400 F (12 V Input).
Con = Distributed hf-Ceramic Decoupling Capacitors for VTT bus; as Recommended for DDR Memory Applications.
PTH03050Y
PTH05050Y
PTH12050Y
SLTS221A–MARCH 2004–REVISED OCTOBER 2005
MEMORY BUS TERMINATION MODULES
50 W/in3 Power Density
VTT Bus Termination Output
Safety Agency Approvals:
(Output Tracks the System VREF)
UL/cUL60950, EN60950, VDE
6 A Output Current (8 A Peak)
Point-of-Load Alliance (POLA) Compatible
3.3-V, 5-V or 12-V Input Voltage
DDR and QDR Compatible
On/Off Inhibit (for VTT Standby)
Undervoltage Lockout
Operating Temperature: –40°Cto85°C
Efficiencies up to 88%
Output Overcurrent Protection (Non-Latching,
Auto-Reset)
The PTHxx050Y are a series of ready-to-use switching regulator modules from Texas Instruments designed
specifically for bus termination in DDR and QDR memory applications. Operating from either a 3.3-V, 5-V or 12-V
input, the modules generate a VTT output that will source or sink up to 6 A of current (8 A transient) to accurately
track their VREF input. VTT is the required bus termination supply voltage, and VREF is the reference voltage for
the memory and chipset bus receiver comparators. VREF is usually set to half the VDDQ power supply voltage.
Both the PTHxx050Y series employs an actively switched synchronous rectifier output to provide state-of-the-art
stepdown switching conversion. The products are small in size (0.87 in × 0.5 in), and are an ideal choice where
space, performance, and high efficiency are desired, along with the convenience of a ready-to-use module.
Operating features include an on/off inhibit and output over-current protection (source mode only). The on/off
inhibit feature allows the VTT bus to be turned off to save power in a standby mode of operation.
Package options include both throughhole and surface mount configurations.
STANDARD APPLICATION
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
POLA is a trademark of Texas Instruments.
PRODUCTION DATA information is current as of publication date.
Copyright 2004–2005, Texas Instruments Incorporated
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.