PT6940 Series
6-A Dual Output 5-V/3.3-V Input
Integrated Switching Regulator
SLTS155B
Revised (4/8/2002)
Features
• Remote Sensing (Vo1 & Vo2)
• Soft-Start
• High Efficiency Dual Output
(See Ordering Information)
• Short-Circuit Protection
(coordinated shutdown)
• Ideal Power Source for DSPs
• 5V/3.3V Input
• 27-pin Space-Saving Package
• Solderable Copper Case
• 6A Rated (Both Outputs)
• Internal Power-up Sequencing
• Single On/Off Control
• Independent Adjust/Trim
Pin-Out Information
Ordering Information
Description
PT 6941o = +3.3/2.5 Volts
PT 6942o = +3.3/1.8 Volts
PT 6943o = +3.3/1.5 Volts
PT 6944o = +3.3/1.2 Volts
† PT 6946o = +2.5/1.8 Volts
† PT 6947o = +2.5/1.5 Volts
† PT 6948o = +2.5/1.2 Volts
Pin Function
The PT6940 Excalibur™ power modules
are a series of high-efficiency dual-output
regulators, housed in a solderable space-
saving package. The dual output is ideal
for DSP applications that require a second
voltage source for a processor core.
Both outputs from the PT6940 regulator
modules are rated to deliver a full 6A load
current simultaneously, and are internally
sequenced to comply with the power-up
requirements of popular DSP ICs.
Each output can be independently
adjusted with a single external resistor, and
incorporates an output sense to compensate
for voltage drop between the regulator and
load. A short-circuit load fault at either
output will result in the coordinated
shutdown of both voltages.
Pin Function
1
2
STBY* †
Vo1 Adjust
Vo1 Sense
Vo1
15
16
1 7
18
19
20
21
22
23
24
25
26
27
Vin
Vin
3
GND
GND
GND
GND
GND
GND
Vo2
4
5
Vo1
6
Vo1
† -Denotes models that will also operate off
3.3V input bus.
7
GND
GND
GND
GND
GND
GND
Vin
8
9
PT Series Suffix
(PT1234x)
10
11
12
13
14
Vo2
Case/Pin
Configuration
Order
Suffix
Package
Vo2
Code
Vo2 Sense
Vo2 Adjust
Vertical
Horizontal
SMD
N
A
C
(ENE)
(ENF)
(ENG)
Vin
(Reference the applicable package code drawing
for the dimensions and PC layout)
† STBY* pin: Open = Outputs enabled
Ground = Outputs disabled
Standard Application
Vo1 Sense
Vo2 Sense
STBY*
1
3
26
Vo1
4–6
VIN
13–16
PT6940
Vo2
23–25
7–12
17–22
+
+
+
CIN
Co1
Co2
L
O
A
D
L
O
A
D
330µF
330µF
330µF
Cin
= Req’d 330µF * electrolytic
Co1/Co2 = Req’d 330µF * electrolytic
GND
GND
*300µF for Oscon® or low ESR tantalum
(see application notes)
For technical support and more information, see inside back cover or visit www.ti.com
TI [ TEXAS INSTRUMENTS ]
