PT7772-3.3V Datasheet, PDF (1/4 Pages) Texas Instruments – Sledge Hammer

PT7772—3.3V
32 Amp “Sledge Hammer”
Programmable ISR
SLTS055A
(Revised 6/30/2000)
The PT7772 is a high-output Inte-
grated Switching Regulator (ISR)
housed in a 27-pin SIP package. The
PT7772 operates from a 3.3V bus to
provide a 32 amp low-voltage power
source for the industry’s latest high-
speed µPs, ASICs, DSPs.
The PT7772 has been designed to
work in parallel with one or more of
the PT7746 -32A current boosters to
increase the load current capability in
increments of 32A.
The output voltage is program-
mable from 1.3V to 2.05V with a 4-bit
input, compatible with Intel’s Pentium^â
Pro Processor. A differential remote
sense is also provided, to compensate
for voltage drop between the ISR and
load.
The PT7772 requires a capacitance
of 2400µF at the input, and 680µF at
the output for proper operation. Note
that this product does not include short
circuit protection.
Standard Application
PROGRAMMING PINS
VID0
VID1
VID2
VID3
V_IN
L1
1H
432 1
26
7 - 11 _PT7772
REMOTE SENSE (+)
20 - 25
V_OUT
SYNC OUT
GND
STBY*
Specifications
+
C_IN
27
13 - 19 5 12
Cin = Required 2400µF electrolytic
Cout = Required 680µF electrolytic
L1 = Optional 1µH input choke
+
C_OUT
LOAD
GND
REMOTE SENSE (-)
Characteristics
(T a = 25°C unless noted)
Output Current
Input Voltage Range
Output Voltage Tolerance
Line Regulation
Load Regulation
Vo Ripple/Noise pk-pk
Transient Response
Efficiency
Switching Frequency
Absolute Maximum
Operating Temperature Range
Storage Temperature
Weight
Symbols
Io
Vin
∆Vo
Regline
Reg_load
Vn
ttr
Vos
ttr
Vos
η
ƒo
Ta
Ts
—
Conditions
Ta = +60°C, 200 LFM, pkg N
Ta = +25°C, natural convection
0.1A ≤ Io ≤ 32A
Vin = +3.3V, Io = 32A
0°C ≤ Ta ≤ +55°C
3.1V ≤ Vin ≤ 3.6V, Io = 32A
V_in = +3.3V, 0.1 ≤ I_o ≤ 32A
Vin = +3.3V, Io = 32A
Cout =680µF, Io =25% load step from 24A
Vo over/undershoot
Cout =2400µF, Io =50% load step from 16A
Vo over/undershoot
Vin = +3.3V, Io = 20A, Vo = 1.8V
3.1V ≤ Vin ≤ 3.6V
0.1A ≤ Io ≤ 32A
—
—
Vertical/Horizontal
Notes: (1) The ISR will operate down to no load with reduced specifications.
(2) The minimum input voltage is 3.1V or V_out+1.2V, whichever is greater.
(3) See Safe Operating Area curves for appropriate derating.
Pin-Out Information
Pin Function
1 VID0
2 VID1
3 VID2
4 VID3
5 STBY*- Stand-by
6 Do not connect
7 V_in
8 V_in
9 V_in
10 V_in
11 V_in
12 Remote Sense Gnd
13 GND
Pin Function
14 GND
15 GND
16 GND
17 GND
18 GND
19 GND
20 Vout
21 Vout
22 Vout
23 Vout
24 Vout
25 Vout
26 Remote Sense Vout
27 Sync Out
For STBY* pin; Open = output enabled
Gnd = output disabled.
PT7772 SERIES
Min
Typ
Max
0.1 (1)
—
32
0.1 (1)
—
26
3.1 (2)
—
3.6
Vo-0.03 —
Vo+0.03
—
±10
—
—
±10
—
—
50
—
—
100
—
—
200
—
—
100
—
—
200
—
—
90
—
650
700
750
0
—
+85 ⁽³⁾
-40
—
+125
—
53/66
—
Units
A
A
V
V
mV
mV
mV
µs
mV
µs
mV
%
kHz
°C
°C
grams
Output Capacitors: The PT7772 series requires a minimum output capacitance of 680µF for proper operation. Do not use Oscon type capacitors.
The maximum allowable output capacitance is 30,000µF.
Input Filter: An input filter is optional for most applications. The input inductor must be sized to handle 32ADC with a typical value of 1µH.
The input capacitance must be rated for a minimum of 2.6Arms of ripple current. For transient or dynamic load applications, additional
capacitance may be required.
For technical support and more information, see inside back cover or visit www.ti.com/powertrends