Texas Instruments PT7749N, PT7749A, PT7749C Datasheet

Features

When used with PT7705/7706:

Cin= Required 1200µF electrolytic
C

out

= Required 1200µF electrolytic

L1 = Optional 1µH input choke

When used with PT7707:

Cin= Required 1200µF electrolytic
C

out

= Required 330µF electrolytic

L1 = Optional 1µH input choke

The PT7749 is a new high-perfor­mance 18 Amp “Current Booster” for
the PT7700 Series housed in a 27-pin
SIP package.

Multiple PT7749 boosters will oper­ate in parallel with the PT7700 boosting
output current in increments of 18A .
Combinations of PT7700s and PT7749
current boosters can easily supply enough
power for virtually any multiple
megaprocessor application.

A PT7749 current booster adds a

parallel output stage driven by the PT7700.
As such, the system runs in perfect
sychronization providing a low noise solu­tion.

The PT7749 only operates in combina­tion with the PT7700 series and is not a
stand-alone product. Therefore please refer
the PT7705, PT7706, or PT7707 series
data sheet for performance specifications.
The PT7749 also has the same mechanical
dimensions and package options as the
PT7700 series.

PT7749

18 AMP “CURRENT BOOSTER”
FOR PT7700 SERIES

Ordering Information

PT7749❏

• Current Boost

• Automatically Tracks Vout of PT7700

• High Efficiency

• Input Voltage Range: 3V to 5.5V

• Synchronized with PT7700

• 27-pin SIP Package

• Run up to 4 in Parallel - 90 Amps

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

Standard Application

Series

(For dimensions and PC Board layout,
see Package Styles 800 and 810.)

40

Pin-Out Information

Pin Function

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

in

7V

in

8V

in

9V

in

10 V

in

11 V

in

12 Do not connect
13 GND
14 GND

Pin Function

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 Master Sync In

For assistance or to order, call [phone]

PT7749

PT7700

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

PT Series Suffix

(PT1234X)

Case/Pin
Configuration

Vertical Through-Hole

N

Horizontal Through-Hole

A

Horizontal Surface Mount

C

Output Capacitors:

When used with a PT7705or PT7706, the PT7749 requires a minimum ouput capacitance of 1200µF. When used with a PT7707, the PT7749

requires a minimum ouput capacitance of 330µF for proper operation. Do not use Oscon type capacitors. The maximum allowable output capacitance is 15,000µF.

Input Filter:

An input filter is optional for most applications. The input inductor must be sized to handle 18ADC with a typical value of 1µH. The input capacitance must be

rated for a minimum of 1.3Arms of ripple current. For transient or dynamic load applications, additional capacitance may be required.

Application Notes

Mechanical Outline

Product Selector Guide

Revised 8/13/98

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