* At temperatures below 0°C, the PT3340 series requires output capacitors with temperature stable dielectrics
such as tantalum or Oscon.
** If pin 2 is left open, the PT3340 will operate when input power is applied.
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PT3340
CHARACTERISTIC
DATA
Series
PT3341, 3.3 VDC
(See Note 1)
PT3342, 5.0 VDC
(See Note 1)
PT3343, 12.0 VDC
(See Note 1)
Efficiency vs Output Current
100
90
100
90
Efficiency vs Output Current
100
90
Efficiency vs Output Current
Efficiency (%)
Efficiency (%)
Efficiency (%)
80
70
60
50
40
0
2
4
6
8
Vin
18.0V
24.0V
36.0V
48.0V
60.0V
80
70
60
50
40
0
1
2
3
4
5
6
Vin
18.0V
24.0V
36.0V
48.0V
60.0V
80
70
60
50
40
0.0
0.5
1.0
1.5
2.0
2.5
Vin
18.0V
24.0V
36.0V
48.0V
60.0V
Iout (A)
Iout (A)
Iout (A)
Ripple vs Output Current
60
50
40
30
20
10
0
0
2
4
6
8
70
60
Ripple vs Output Current
120
100
Ripple vs Output Current
Ripple (mV)
Ripple (mV)
Vin
18.0V
24.0V
36.0V
48.0V
60.0V
50
40
30
20
10
0
0
1
2
3
4
5
6
Ripple (mV)
Vin
18.0V
24.0V
36.0V
48.0V
60.0V
80
60
40
20
0
0.0
0.5
1.0
1.5
2.0
2.5
Vin
18.0V
24.0V
36.0V
48.0V
60.0V
Iout (A)
Iout (A)
Iout (A)
Power Dissipation vs Output Current
10
8
Power Dissipation vs Output Current
7
6
Power Dissipation vs Output Current
8
6
PD (Watts)
6
4
18.0V
24.0V
36.0V
48.0V
60.0V
PD (Watts)
4
18.0V
24.0V
36.0V
48.0V
60.0V
PD (Watts)
Vin
Vin
5
4
3
2
1
Vin
18.0V
24.0V
36.0V
48.0V
60.0V
2
2
0
0
2
4
6
8
0
0
1
2
3
4
5
6
0
0.0
0.5
1.0
1.5
2.0
2.5
Iout (A)
Iout (A)
Iout (A)
Safe Operating Area (@Vin=24V)
90
90
Safe Operating Area (@Vin=24V)
90
Safe Operating Area (@Vin=24V)
Ambient Temperature (°C)
80
70
60
50
40
30
20
Ambient Temperature (°C)
70
60
50
40
30
20
0
2
4
6
8
Airflow
Na t co nv
60LFM
120LF M
200LF M
Ambient Temperature (°C)
80
80
70
60
50
40
30
20
0
1
2
3
4
5
6
Airflow
Nat conv
60LFM
120LF M
200LF M
Airflow
Na t co nv
60LFM
120LF M
200LF M
0
0.5
1
1.5
2
2.5
Iout (A)
Iout (A)
Iout (A)
Note 1:
All data listed in the above graphs has been developed from actual products tested at 25°C. This data is considered typical data for the DC-DC Converter.
Power Trends, Inc.
27715 Diehl Road, Warrenville, IL 60555
(800) 531-5782
Fax: (630) 393-6902
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For assistance or to order, call
(800) 531-5782
Application
Notes
PT3320/3340 Series
More Application Notes
Adjusting the Output Voltage of the PT3320 /
PT3340 Series of Isolated DC-DC Converters
The factory pre-set output voltage of Power Trends’ PT3320
and PT3340 series DC-DC converters may be adjusted within a
nominal ±10% range. This is accomplished with the addition of
a single external resistor. For the input voltage range specified in
the data sheet, Table 1 gives the allowable adjustment range for
each model as V
o
(min) and V
o
(max).
Adjust Up:
An increase in the output voltage is obtained by
adding a resistor, R2 between pin 18 (V
o
adjust), and pin 13
(-Remote Sense).
See note 4
.
Adjust Down:
Add a resistor
(R1),
between pin 18 (V
o
adjust)
and pin 19 (+Remote Sense).
Refer to Figure 1 and Table 2 for both the placement and value
of the required resistor,
(R1)
or R2.
Notes:
1. Use only a single 1% resistor in either the
(R1)
or R2 loca-
tion. Place the resistor as close to the ISR as possible.
2. Never connect capacitors to V
o
adjust. Any capacitance
added to the V
o
adjust control pin will affect the stability of
the ISR.
Table 1
DC-DC CONVERTER ADJUSTMENT RANGE AND FORMULA PARAMETERS
Series Pt #
24V Bus
48V Bus
Vo(nom)
Vo(min)
Vo(max)
Vr
Ro (kΩ)
Ω
Rs (kΩ)
Ω
PT3341
PT3321
3.3
2.95
3.65
1.225
33.2
150.0
3. If the remote sense pins are not being used, the resistors
(R1)
and R2 can be connected to +V
out
or -V
out
respectively.
4. The adjusted output voltage V
a
effectively sets the voltage
across pins 13 and 19 (±Remote Sense). When using the
remote sense pins, V
out
(measured directly across pins 10–12,
and 14–17) can be significantly higher than V
a
, and may
exceed V
o
(max). If V
a
is adjusted upward, the alternative is
to increase the minimum input voltage by the same percent-
age as V
out
exceeds V
o
(max).
The values of
(R1)
[adjust down], and R2 [adjust up], can also be
calculated using the following formulas.
(R1)
=
R
o
(V
o
– V
r
)(V
a
– V
r
)
V
r
(V
o
– V
a
)
R
o
(V
o
– V
r
)
(V
a
– V
o
)
V
o
V
a
V
r
R
o
R
s
– R
s
– R
s
kΩ
R2
Where
=
kΩ
= Original output voltage
= Adjusted output voltage
= Reference voltage (Table 1)
= Multiplier resistance (Table 1)
= Series resistance (Table 1)
PT3325
2.0V
1.8V
2.2
1.225
80.6
150.0
PT3326
2.5
2.25
2.75
1.225
33.2
121.0
PT3342
PT3322
5.0
4.5
5.5
1.225
18.2
121.0
PT3343
PT3323
12.0
10.8
13.2
2.5
14.3
90.9
PT3344
PT3324
15.0
13.5
16.5
2.5
11.0
80.6
Figure 1
2
Inhibit
7, 8, 9
19
Sns(+)
14 - 17
+V
in
+Vin
PT3320/3340
-Vin
4, 5, 6
-Vout
Sns(-)
10 - 12
13
+Vout
+V
Vo(adj)
18
Cin
100
µF
100V
(Optional)
(R1)
Adj Down
+
Cout
330
µF
R2
Adj Up
+
L
O
A
D
-V
in
-V
Power Trends, Inc.
27715 Diehl Road, Warrenville, IL 60555
(800) 531-5782
Fax: (630) 393-6902
http://www.powertrends.com
3
For assistance or to order, call
(800) 531-5782
PT3320/3340 Series
Application
Notes
Table 2
PT3320 / PT3340 ADJUSTMENT RESISTOR VALUES
Series Pt #
24V Bus
48V Bus
Current
V
o
(nom)
V
a
(req’d)
1.8
1.85
1.9
1.95
2.0
2.05
2.1
2.15
2.2
2.25
2.3
2.35
2.4
2.45
2.5
2.55
2.6
2.65
2.7
2.75
2.95
3.0
3.05
3.1
3.15
3.2
3.25
3.3
3.35
3.4
3.45
3.5
3.55
3.6
3.65
1230.0kΩ
539.0kΩ
309.0kΩ
194.0kΩ
126.0kΩ
79.6kΩ
46.8kΩ
726.0kΩ
302.0kΩ
161.0kΩ
90.6kΩ
48.3kΩ
(127.0)kΩ
(183.0)kΩ
(261.0)kΩ
(377.0)kΩ
(572.0)kΩ
(961.0)kΩ
(2130.0)kΩ
1100.0kΩ
475.0kΩ
266.0kΩ
162.0kΩ
(20.7)kΩ
(64.7.0)kΩ
(138.0)kΩ
(285.0)kΩ
(726.0)kΩ
PT3341
PT3321
8Adc
3.3Vdc
V
a
(req’d
0.0kΩ
(62.5)kΩ
(194.0)kΩ
(589.0)kΩ
4.5
4.55
4.6
4.65
4.7
4.75
4.8
4.85
4.9
4.95
5.0
5.05
5.1
5.15
5.2
5.25
5.3
5.35
5.4
5.45
5.5
566.0kΩ
337.0kΩ
223.0kΩ
154.0kΩ
108.0kΩ
75.3kΩ
50.8kΩ
31.7kΩ
16.4kΩ
13.5
13.6
13.8
14.0
14.2
14.4
14.6
14.8
15.0
15.2
15.4
15.6
15.8
16.0
16.5
607.0kΩ
263.0kΩ
149.0kΩ
91.3kΩ
56.9kΩ
11.1kΩ
(323.0)kΩ
(355.0)kΩ
(437.0)kΩ
(522.0)kΩ
(724.0)kΩ
(1010.0)kΩ
(1580.0)kΩ
(246.0)kΩ
(293.0)kΩ
(352.0)kΩ
(428.0)kΩ
(529.0)kΩ
(670.0)kΩ
(882.0)kΩ
(1230.0)kΩ
(1940.0)kΩ
PT3342
PT3322
6adc
5.0Vdc
V
a
(req’d)
10.8
11.0
11.2
11.4
11.6
11.8
12.0
12.2
12.4
12.6
12.8
13.0
13.2
588.0kΩ
249.0kΩ
136.0kΩ
78.9kΩ
45.0kΩ
22.3kΩ
(285.0)kΩ
(371.0)kΩ
(500.0)kΩ
(715.0)kΩ
(1150.0)kΩ
PT3343
PT3323
2.5Adc
12.0Vdc
PT3344
PT3324
2.0Adc
15.0Vdc
PT3325
8Adc
2.0Vdc
PT3326
8Adc
2.5Vdc
R1 =
(Red)
R2 = Black
4
Power Trends, Inc.
27715 Diehl Road, Warrenville, IL 60555
(800) 531-5782
Fax: (630) 393-6902
http://www.powertrends.com
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