(Reference the applicable package code drawing for the
dimensions and PC board layout)
Standard Application
* For further information, see
application notes.
V
o
ADJ
14
1
11,12,13
V
o
SENSE
V
IN
4,5,6
PT6520
3
7–10
V
OUT
+
+
C
IN
C
OUT
LOAD
COM
COM
For technical support and more information, see inside back cover or visit www.ti.com
PT6520 Series
8-A 5-V/3.3-V Input Adjustable ISR
with Short-Circuit protection
Specifications
Characteristic
(Unless otherwise stated, T
a
=25°C, V
in
=5V, C
in
=330µF, C
out
=330µF, and I
o
=I
o
max)
Symbol
I
o
V
in
V
o
tol
Reg
temp
Reg
line
Reg
load
∆V
o
tot
η
Conditions
Over V
in
range
Over I
o
Range
V
o
=3.3V
V
o
≤2.5V
Min
0.1
(1)
4.5
3.1
—
—
—
—
—
V
o
=3.3V
V
o
=2.5V
V
o
=2.1V
V
o
=1.8V
V
o
=1.5V
V
o
=1.2V
V
o
=3.3V
V
o
=2.5V
V
o
=2.1V
V
o
=1.8V
V
o
=1.5V
V
o
=1.2V
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
300
—
–0.1
—
—
330
330
-40
-40
6.3
—
—
—
—
—
—
—
PT6520 SERIES
Typ
Max
—
—
—
±1
±0.5
±5
±5
±2
92
88
85
82
80
75
89
85
82
78
75
71
35
50
±70
12
350
—
—
–0.5
15
—
—
—
—
—
500
7.5
TBD
(4)
12.5
16.5
15.25
22
8.0
5.5
5.5
±1.5
—
±10
±10
±3
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
22.5
400
Open
(2)
+0.4
–
25
5,000
—
+85
(3)
+125
—
—
—
—
—
—
—
—
Units
A
VDC
%V
o
%V
o
mV
mV
%V
o
Output Current
Input Voltage Range
Set Point Voltage T
olerance
Temperature Variation
Line Regulation
Load Regulation
Total Output Voltage Variation
Efficiency
–40°
≤T
a
≤
+85°C, I
o
=I
o
min
Over V
in
range
Over I
o
range
Includes set-point, line, load,
–40°
≤T
a
≤
+85°C
I
o
=3.0A
%
I
o
=8.0A
%
V
o
Ripple (pk-pk)
Transient Response
Short Circuit Threshold
Switching Frequency
Remote On/Off (Pin 1)
Input High Voltage
Input Low Voltage
Input Low Current
Standby Input Current
External Output Capacitance
External Input Capacitance
Operating T
emperature Range
Storage T
emperature
Reliability
Mechanical Shock
Mechanical Vibration
Mil-Std-883D, 20-2000Hz
Weight
V
r
t
tr
∆V
tr
I
sc
threshold
ƒ
s
V
IH
V
IL
I
IL
I
in
standby
C
out
C
in
T
a
T
s
MTBF
—
—
—
20MHz bandwidth
1A/µs load step, 50% to 100% I
o
max
V
o
over/undershoot
Over V
in
and I
o
range
Referenced to –V
in
(pin 7)
mV
pp
µs
mV
A
kHz
V
mA
mA
µF
µF
°C
°C
10
6
Hrs
G’s
G’s
grams
Flammability
—
pins 3 & 7 connected
See application schematic
See application schematic
Over V
in
range
—
Per Bellcore TR-332
50% stress, T
a
=40°C, ground benign
Per Mil-Std-883D, method 2002.3,
1ms, half-sine, mounted to a fixture
Suffixes P D, & E
,
Suffixes L & M
Suffixes P D, & E
,
Suffixes R, G & B
Suffixes L & M
Suffixes Q & F
Materials meet UL 94V-0
Notes:
(1) The ISR will operate at no load with reduced specifications.
(2) The STBY* control (pin 3) has an internal pull-up and if it is left open circuit the module will operate when input power is applied. The open-circuit
voltage is typically 12.6V, and maybe as high as 15V. Refer to the application notes for other interface considerations.
(3) See Safe Operating Area curves or contact the factory for the appropriate derating.
(4) The tab pins on the 16-pin mount package types (suffixes L & M) must be soldered. For more information see the applicable package outline drawing.
Input/Output Capacitors:
The PT6520 series requires a 330µF capacitor at both the input and output for proper operation in all applications. In addition, the input
capacitance (C
in
) must be rated for a minimum of 1.2Arms ripple current rating. For transient or dynamic load applications, additional output capacitance (C
out
) may be
necessary. The maximum allowable output capacitance is 5,000µF. For more information consult the related application note on capacitor recommendations.
For technical support and more information, see inside back cover or visit www.ti.com
PT6520 Series
8-A 5-V/3.3-V Input Adjustable ISR
with Short-Circuit protection
Typical Characteristics
Characteristic Data; V
in
=5.0V
Efficiency vs Output Current
100
(See Note A)
Characteristic Data; V
in
=3.3V
Efficiency vs Output Current
100
90
(See Note A)
90
V
OUT
Efficiency - %
3.3V
2.5V
1.8V
1.2V
Efficiency - %
80
80
V
OUT
2.5V
1.8V
1.2V
70
70
60
60
50
50
40
0
1
2
3
4
5
6
7
8
40
0
1
2
3
4
5
6
7
8
Iout (A)
Iout (A)
Output Ripple vs Output Current
40
35
30
40
35
Output Ripple vs Output Current
V
OUT
3.3V
2.5V
1.8V
1.2V
Ripple - mV
30
V
OUT
25
20
15
10
5
0
Ripple - mV
25
20
15
10
5
0
0
1
2
3
4
5
6
7
8
2.5V
1.8V
1.2V
0
1
2
3
4
5
6
7
8
Iout (A)
Iout (A)
Power Dissipation vs Output Current
5
5
Power Dissipation Output Current
4
4
V
OUT
Pd - Watts
3
V
OUT
Pd - Watts
3
2
1.2V
1.8V
2.5V
3.3V
2
1.2V
1.8V
2.5V
1
1
0
0
1
2
3
4
5
6
7
8
0
0
1
2
3
4
5
6
7
8
Iout (A)
Iout (A)
Safe Operating Area; V
in
=5V
(See Note B)
90
80
70
60
50
40
30
20
0
1
2
3
4
5
6
7
8
90
80
Safe Operating Area; 3.3V
(See Note B)
Airflow
200LFM
120LFM
60LFM
Nat conv
Ambient Temperature (°C)
Ambient Temperature (°C)
70
60
50
40
30
20
0
1
2
3
4
5
6
7
8
Airflow
200LFM
120LFM
60LFM
Nat conv
Iout (A)
Iout (A)
Note A:
Characteristic data has been developed from actual products tested at 25°C. This data is considered typical data for the Converter.
Note B:
SOA curves represent the conditions at which internal components are at or below the manufacturer’s maximum operating temperatures
For technical support and more information, see inside back cover or visit www.ti.com
Application Notes
PT6520 Series
Using the Standby Function of the PT6520
Series of Integrated Switching Regulators
The PT6520 series of power modules are high efficiency
regulators that operate off either a 3.3V or 5V input
bus voltage. These regulators incorporate a
Standby
function, which may be used in applications that require
power-up/shutdown sequencing, and wherever there is a
requirement for the output status of the module to be
controlled by external circuitry.
The standby function is provided by the
STBY*
control,
pin 3. If pin 3 is left open-circuit
1
the regulator operates
normally, and provides a regulated output when a valid
supply voltage is applied to V
in
(pins 4–6) with respect
to GND (pins 7–10). If a low voltage
2
is then applied
to pin 3 the regulator output will be disabled and the
input current drawn by the ISR will be reduced to about
15mA
3
. The standby control may also be used to hold-off
the regulator output during the period that input power is
applied.
Pin 3 is ideally controlled with an open-collector (or open-
drain) discrete transistor (See Figure 1). The open-circuit
voltage is typcially 12.6V. Table 1 gives the circuit pa-
rameters for this control input.
Table 1 Standby Control Requirements
(2, 3)
Parameter
Min
Typ
Input Low (V
IL
)
I
stby
(pin 3 =ground)
V
stby
(open circuit)
–0.1V
–0.5mA
12.6V
Figure 1
1
Vo(sense)
4,5,6
11,12,13
V
in
+
C
in
Vin
PT6520
STBY
3
GND
7,8,9,10
Vo
V
o
+
Vo(adj)
14
C
out
COM
Q1
BSS138
COM
Inhibit
Max
+0.4V
15V
Turn-On Time:
In the circuit of Figure 1, turning Q
1
on applies
a low voltage to the STBY control (pin 3) and disables the
regulator ouput. Correspondingly, turning Q
1
off removes the
low-voltage signal and enables the output. Once enabled, the
output will typically experience a 10–15ms delay followed by a
predictable ramp-up of voltage. The regulator should provide a
fully regulated output voltage within 40ms. The waveform of
Figure 2 shows the output voltage and input current waveforms
of a PT6521 (3.3V) following the turn-off of Q
1
. The turn off
of Q
1
corresponds to the rise in Vstby. The waveforms were
measured with a 5Vdc input voltage, and 4.5A resistive load.
Notes:
1 The standby control input requires no external pull-up
resistor. The open-circuit voltage of the STBY* pin is
typically 12.6V.
2. The standby control input is
Not
compatible with TTL or
other devices that incorporate a totem-pole output drive.
Use only a true open-collector device, preferably a discrete
bipolar transistor (or MOSFET). To ensure the regulator
output is disabled, the control pin must be pulled to less
than 0.4Vdc with a low-level 0.5mA sink to ground.
3. When the regulator output is disabled the current drawn
from the input source is typically reduced to 15mA.
Figure 2
Vo (1V/Div)
Iin (2A/Div)
Vstby (10V/Div)
HORIZ SCALE: 5ms/Div
For technical support and more information, see inside back cover or visit www.ti.com