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Point-of-Load Alliance (POLA)
Compatible
Description
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 V
TT
output that will source or sink up
to 6 A of current (8 A transient) to accu-
rately track their V
REF
input. V
TT
is the
required bus termination supply voltage,
and V
REF
is the reference voltage for the
memory and chipset bus receiver com-
parators. V
REF
is usually set to half the
V
DDQ
power supply voltage.
Both the PTHxx050Y series employs
an actively switched synchronous rectifier
output to provide state-of-the-art step-
down switching conversion. The products
are small in size (0.87 in
脳
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 V
TT
bus to be turned
off to save power in a standby mode of
operation.
Package options include both through-
hole and surface mount configurations.
Pin Configuration
Pin
1
2
3
4
5
6
Function
GND
V
REF
V
IN
Inhibit *
No Connect
V
TT
* Denotes negative logic:
Open
= V
TT
Output On
Ground = V
TT
Output Off
Standard Application
V
IN
V
DDQ
1k
1%
1
2
1k
1%
3
4
V
REF
V
TT
6
PTHxx050Y
(Top View)
5
Co
n
hf-Ceramic
V
TT
Termination Island
C
IN
(Required)
Q
1
BSS138
(Optional)
Co
1
Low-ESR
(Required)
Co
2
Ceramic
(Optional)
Standby
SSTL-2
Data/
Address
Bus
GND
Cin
Co
1
Co
2
Co
n
=
=
=
=
Required electrolytic capacitor; 220 碌F (3.3-/5-V input), 560 碌F (12-V input).
Required low-ESR electrolyitic capacitor; 470 碌F (3.3-/5-V input), 940 碌F (12-V input).
Ceramic capacitance for optimum response to a 3-A (鹵1.5-A) load transient.; 200 碌F (3.3-/5-V input), 400 碌F (12-V input).
Distributed hf-ceramic decoupling capacitors for V
TT
bus; as recommended for DDR memory appications.
For technical support and further information, visit http://power.ti.com
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