
For assistance or to order, call (800) 531-5782
PT4205
Series
3-7 WATT 24V INPUT
ISOLATED DC-DC CONVERTER
Application Notes
Mechanical Outline
Product Selector Guide
Revised 5/15/98
• Wide Input Voltage Range:
18V to 36V
• 84% Efficiency
• 1,500 VDC Isolation
• 18 Pin - DIP Package
• 3.5 Million Hour MTBF
• Meets FCC/EN55022 Class A
• UL and CSA approved
DC converters advance the state-of-the-art for boardmounted converters by employing high switching
frequencies, thick-film technology and a high degree
of silicon integration. The high reliability and very low
package height makes these converters ideal for
Telecom and Datacom applications requiring inputto-output isolation with board spacing down to 0.6”.
• No External Components Required
• Adjustable Output Voltage
through-hole or SMD-DIP package with single
output voltages of 3.3V and 5V.
Standard Application
18
1
+Vout
2
-Vout
3
4
NC
5
6
nc
7
S
Vad
8
NOR
9
Specifications
Characteristics
(Ta = 25°C unless noted) Symbols Conditions Min Typ Max Units
Output Current I
Current Limit I
On/Off Standby Current I
Short Circuit Current I
Inrush Current I
Input Voltage Range V
Output Voltage Tolerance ∆V
Idling Voltage V
Ripple Rejection RR Over Vin range @ 120 Hz — 60 — dB
Line Regulation Reg
Load Regulation Reg
Vo Ripple/Noise V
Transient Response t
Efficiency η Vin=24V, Io=1.8A, Vo=3.3V — 79 — %
Switching Frequency ƒ
Pin Temperature T
Operating Temperature T
Storage Temperature T
Mechanical Shock — Per Mil-STD-202F, Method 213B,
Mechanical Vibration — Per Mil-STD-202F, Method 204D,
Weight — — — 20 — grams
Isolation — — 1500 — — VDC
Flammability — Materials meet UL 94V-0
** Minimum input voltage is adjustable - See application note.
o
cl
in standby
sc
ir
t
ir
in
o
n
tr
o
p
a
s
Over Vin range Vo = 3.3V 0 — 1.8 A
Vin = 24V Vo = 3.3V 2.0 — 3.0 A
Vin = 24V, Pin 11 = -V
Vin = 24V Vo = 3.3V — 2.5 — A
Vin = 24V @ max I
On start-up — 1.0 2.0 mSec
Over Io Range 18** 24 36 V
Over Io Range — ±4 — %Vo
o
Io = 0A Vo = 3.3V — 3.65 4.0 V
Over Vin range @ max I
line
10% to 100% of Io max — ±3 — %V
load
Vin=24V, Io=Io max — 30 70 mV
50% load change — 100 300 µSec
Vo over/undershoot — 3.0 5.0 %V
Vin=24V, Io=1.2A, Vo=5V — 84 — %
Over Vin and I
@ Pin 1 — — +95 °C
Vin = 24V @ max I
Free air convection, (40-60LFM)
— -55 — +125 °C
6mS, half-sine, mounted to a PCB
10-500Hz, mounted to a PCB
PT4205
Vo = 5V 0 — 1.2 A
Vo = 5V 1.3 1.6 2.4 A
in
Vo = 5V — 2.0 — A
o
Vo = 5V — 5.6 6.0 V
o
o
-Vin
17
+Vin
16
15
NC
14
13
12
11
RC
10
TOA
PT4205 SERIES
— 0.5 — mA
— 0.6 1.0 A
o
— ±0.5 — %V
520 — 688 kHz
-40 — +85 °C
—50—G’s
—10—G’s
Power Trends’ PT4205 series of isolated DC to
The PT4205 series is offered in a unique molded
Pin-Out Information
Pin Function
1V
out
2V
3 Do not connect
4 Do not connect
5 Do not connect
6 Do not connect
7 Sync input
8* V
9*
10
11 Remote on/off
12 Do not connect
13 Do not connect
14 Do not connect
15 Do not connect
16 Do not connect
o
o
pp
o
17 +V
18 -V
* Please note that when the
Vout adjust is not used, pin 8
must be connected to pin 9.
return
out
adj
Nominal output
voltage resistor
Turn-on/off input
voltage adjust
in
in
Ordering Information
Through-Hole
PT4205A = 3.3V/1.8A
PT4206A = 5V/1.2A
Surface Mount
PT4205C = 3.3V/1.8A
PT4206C = 5V/1.2A
(For dimensions and PC
board layout, see Package
Style 900.)
60
Power Trends, Inc. 27715 Diehl Road, Warrenville, IL 60555 (800) 531-5782 Fax: (630) 393-6902 http://www.powertrends.com

For assistance or to order, call (800) 531-5782
PT4205 Series
CHARACTERISTIC DATA
PT4205, 3.3 VDC (See Note 1) PT4206 5.0 VDC (See Note 1)
Efficiency vs Output Current Efficiency vs Output Current
100
90
80
70
Efficiency (%)
60
50
40
0 0.3 0.6 0.9 1.2 1.5
Vin
18.0V
24.0V
30.0V
36.0V
Output Current (Amps)
Ripple vs Output Current Ripple vs Output Current
35
30
25
20
Ripple (mVpp)
15
10
5
0
0 0.3 0.6 0.9 1.2 1.5 1.8
Output Current (Amps)
Vin
36.0V
30.0V
24.0V
18.0V
100
90
80
70
Efficiency (%)
60
50
40
0 0.2 0.4 0.6 0.8 1 1.2
Output Current (Amps)
18
16
14
12
10
Ripple (mVpp)
8
6
4
2
0
0 0.2 0.4 0.6 0.8 1 1.2
Output Current (Amps)
DATA SHEETS
24V Bus Products
Vin
18.0V
24.0V
30.0V
36.0V
Vin
36.0V
30.0V
24.0V
18.0V
Power Dissipation vs Output Current Power Dissipation vs Output Current
2.5
2
1.5
Pd (Watts)
1
0.5
0
0 0.3 0.6 0.9 1.2 1.5
Vin
36.0V
30.0V
24.0V
18.0V
Output Current (Amps)
Note 1: All data listed in the above graphs, except for derating data, has been developed from actual products tested at 25°C. This data is considered typical data for the isolated DC-DC converter.
1.8
1.6
1.4
1.2
1
Pd (Watts)
0.8
0.6
0.4
0.2
0
0 0.2 0.4 0.6 0.8 1 1.2
Output Current (Amps)
Vin
36.0V
30.0V
24.0V
18.0V
Power Trends, Inc. 27715 Diehl Road, Warrenville, IL 60555 (800) 531-5782 Fax: (630) 393-6902 http://www.powertrends.com
61

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