PT7742—3.3V
20 Amp “Current Booster” for PT7708
Integrated Switching Regulator
SLTS085
(Revised 6/30/2000)
Description
The PT7742 is a 20 Amp “Current
Booster” for the PT7708 housed in the
same 27-pin SIP package.
Multiple PT7742 boosters will
operate in parallel with one PT7708
product, boosting output current in
increments of 20A. Combinations of a
PT7708 regulator and PT7742 current
boosters can supply power for virtually
any multiple mega-processor applica-
tion.
parallel output stage that is driven di-
rectly by the regulator. This allows
the system to run in perfect synchron-
ization to provide a low noise solution.
The PT7742 only operates in com-
bination with a PT7708 series regulator,
and is not a stand-alone product. Please
refer to the PT7708 data sheet for the
performance specifications.
The booster uses the same 27-pin
case and has the same package options
as its companion regulator.
A PT7742 current booster adds a
Pin-Out Information
Ordering Information
PT7742J
Pin Function
Pin Function
14 GND
15 GND
16 GND
17 GND
18 GND
19 GND
20 Vout
(For dimensions and PC Board layout, see
Package Styles 800 and 810.)
1
2
3
4
5
6
7
8
9
Do not connect
Do not connect
Do not connect
Do not connect
Do not connect
Do not connect
Vin
Features
• 20A Current Boost
• Tracks Vo of a PT7708
• High Efficiency
• Input Voltage Range:
3.1V to 3.6V
PT Series Suffix
(PT1234X)
Case/Pin
Configuration
Vertical Through-Hole
N
A
C
Vin
21 Vout
• Synchronized with PT7708
• 27-pin SIP Package
• Connect up to 2 in Parallel for
60 Amps
Horizontal Through-Hole
Vin
22 Vout
Horizontal Surface Mount
10 Vin
23 Vout
11 Vin
24 Vout
12 Do not connect
13 GND
25 Vout
26 Do not connect
27 Master Sync In
Standard Application
PROGRAMMING PINS
REMOTE SENSE (+)
VID0
VID1
VID2
VID3
4
VID3
3
-
2
VID0
1
26
SNS(+)
VOUT
L1
7-11
20-25
Vo
Vin
VIN
PT7708
1 H
Synch
Out
STBY
5
GND
SNS(-)
+
+
LOAD
27
13-19 12
CIN
COUT
GND
GND
STBY*
REMOTE SENSE
( )
27
Synch
In
L1
7-11
20-25
Vo
Vin
PT7742
1 H
GND
+
+
13-19
CIN
COUT
External Capacitors: The PT7742 requires a minimum ouput capacitance of 330µF for proper operation. The PT7742 also requires an input capacitance of
1500µF, which must be rated for a minimum of 1.4Arms of ripple current. For transient or dynamic load applications additional capacitance may be required.
For more information refer to the application note regarding capacitor selection for this product.
Input Filter: An input filter inductor is optional for most applications. The inductor must be sized to handle 20ADC with a typical value of 1µH.
For technical support and more information, see inside back cover or visit www.ti.com/powertrends