Texas Instruments PT7747A, PT7747C, PT7747N Datasheet

• 15A Current Boost

• Automatically Tracks Vout of PT7750

• High Efficiency

• Input Voltage Range:

20V to 28V

• Synchronized with PT7750

• 27-pin SIP Package

• Run up to 4 in Parallel - 60 Amps

Standard Application

Cin= Required 560µF electrolytic
C

out

= Required 2000µF electrolytic

L1 = Optional 1µH input choke

15 AMP “CURRENT BOOSTER”
FOR PT7750 SERIES

PT7747

Ordering Information

PT7747

❏❏

❏❏

❏

The PT7747 is a new high-perfor­mance 15 Amp “Current Booster” for
the PT7750 Series housed in a 27-pin
SIP package. Multiple PT7747 boost­ers will operate in parallel with the
PT7750 Series boosting output current
in increments of 15A . Combinations
of PT7750s and PT7747 current
boosters can easily supply enough
power for virtually any multiple
megaprocessor application.

A PT7747 current booster adds a parallel
output stage driven by the PT7750. As such,
the system runs in perfect sychronization
providing a low noise solution.

The PT7747 only operates in combina­tion with the PT7750 series and is not a
stand-alone product. Therefore please refer
the PT7750 series data sheet for perfor­mance specifications. The PT7747 also has
the same mechanical dimensions and pack­age options as the PT7750 series.

Features

Output Capacitors:

The PT7750/PT7747 series requires a minimum output capacitance of 2000µF for proper operation. Do not use Oscon type capacitors. The maximum

allowable output capacitance is (42,000

4

Vout)µF for the PT7751, (96,000 4 Vout)µF for the PT7756, or 15,000µF, whichever is less.

Input Filter:

An input inductor is optional for most applications. The input inductor must be sized to handle 9ADC with a typical value of 1µH. The input capacitance
must be rated for a minimum of 8.0 Arms of ripple current when operated at maximum output current and maximum output voltage. Contact an applications engi­neer for input capacitor selection for applications at other output voltages and output currents.

Pin Function

1 Do not connect
2 Do not connect
3 Do not connect
4 Do not connect
5 Do not connect
6 Do not connect
7V

in

8V

in

9V

in

10 V

in

11 V

in

12 Do not connect
13 GND

Pin Function

14 GND
15 GND
16 GND
17 GND
18 GND
19 GND
20 V

out

21 V

out

22 V

out

23 V

out

24 V

out

25 V

out

26 Do not connect
27 Sync In

Pin-Out Information

PT7747

PT7750

7 - 11

13 - 19

20 - 25

27

GND GND

V

OUT

12

261

REMOTE SENSE (+)

REMOTE SENSE (-)

VID0
VID1
VID2
VID3

PROGRAMMING PINS

234

STBY*

5

C

IN

+

C

IN

+

C

OUT

+

C

OUT

+

LOAD

7 - 11 20 - 25

13 - 19

27

1µH

L1

1µH

L1

V

IN

6

VID4

Series

For assistance or to order, call [phone]

58

Power Trends, Inc. 27715 Diehl Road, Warrenville, IL 60555 [phone] Fax: [phone] http://www.powertrends.com

PT Series Suffix

(PT1234X)

Case/Pin
Configuration

Vertical Through-Hole

N

Horizontal Through-Hole

A

Horizontal Surface Mount

C

(For dimensions and PC board layout,
see Package Styles 1000 and 1010.)

Revised 1/12/99

Application Notes

Mechanical Outline

Product Selector Guide

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