Application Notes
Mechanical Outline
For assistance or to order, call (800) 531-5782
Product Selector Guide
P T 4 2 0 5 S e r i e s
3-7 WATT 24V INPUT
ISOLATED DC-DC CONVERTER
Revised 5/15/98
• Wide Input Voltage Range:
18V to 36V
• 84% Efficiency
Power Trends’ PT4205 series of isolated DC to
DC converters advance the state-of-the-art for board-
mounted 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 input-
to-output isolation with board spacing down to 0.6”.
The PT4205 series is offered in a unique molded
through-hole or SMD-DIP package with single
output voltages of 3.3V and 5V.
• 1,500 VDC Isolation
• 18 Pin - DIP Package
• 3.5 Million Hour MTBF
• Meets FCC/EN55022 Class A
• UL and CSA approved
• No External Components Required
• Adjustable Output Voltage
Pin-Out Information
Standard Application
+Vout
-Vout
1
2
3
4
5
6
7
8
9
18
17
16
15
14
13
12
11
10
-Vin
+Vin
Pin
Function
1
2
V
V
out
out
N C
N C
return
3
Do not connect
Do not connect
Do not connect
Do not connect
Sync input
Sync
Vadj
N O R
R C
T O A
4
PT4205
Specifications
5
PT4205 SERIES
Characteristics
(Ta = 25°C unless noted)
6
Symbols
Conditions
Min
Typ
Max
Units
7
Output Current
Io
Over Vin range
Vo = 3.3V
Vo = 5V
0
0
—
—
1.8
1.2
A
A
8*
Vadj
Nominal output
voltage resistor
Current Limit
Icl
Vin = 24V
Vo = 3.3V
Vo = 5V
2.0
1.3
—
3.0
2.4
A
A
9*
1.6
On/Off Standby Current
Short Circuit Current
Iin standby
Isc
Vin = 24V, Pin 11 = -Vin
—
0.5
—
mA
Turn-on/off input
voltage adjust
10
Vin = 24V
Vo = 3.3V
Vo = 5V
—
—
2.5
2.0
—
—
A
A
11
12
13
14
15
16
17
18
Remote on/off
Do not connect
Do not connect
Do not connect
Do not connect
Do not connect
Inrush Current
Iir
tir
Vin = 24V @ max Io
On start-up
—
—
0.6
1.0
1.0
2.0
A
mSec
Input Voltage Range
Vin
Over Io Range
Over Io Range
Io = 0A
18**
—
24
±4
36
—
V
Output Voltage Tolerance ∆Vo
%Vo
Idling Voltage
Vo
Vo = 3.3V
Vo = 5V
—
—
3.65
5.6
4.0
6.0
V
V
Ripple Rejection
Line Regulation
Load Regulation
Vo Ripple/Noise
Transient Response
RR
Over Vin range @ 120 Hz
Over Vin range @ max Io
10% to 100% of Io max
Vin=24V, Io=Io max
—
—
—
—
60
—
—
—
70
dB
+V
in
Regline
Regload
Vn
±0.5
±3
%Vo
%Vo
mVpp
-V
in
* Please note that when the
Vout adjust is not used, pin 8
must be connected to pin 9.
30
ttr
50% load change
Vo over/undershoot
—
—
100
3.0
300
5.0
µSec
%Vo
Efficiency
η
Vin=24V, Io=1.8A, Vo=3.3V
Vin=24V, Io=1.2A, Vo=5V
—
—
79
84
—
—
%
%
Ordering Information
Through-Hole
PT4205A = 3.3V/1.8A
PT4206A = 5V/1.2A
Switching Frequency
Pin Temperature
ƒo
Over Vin and Io
@ Pin 1
520
—
—
—
688
+95
kHz
°C
Tp
Ta
Operating Temperature
Vin = 24V @ max Io
-40
-55
—
—
—
50
+85
+125
—
°C
°C
G’s
Free air convection, (40-60LFM)
Storage Temperature
Mechanical Shock
Ts
—
—
Per Mil-STD-202F, Method 213B,
6mS, half-sine, mounted to a PCB
Surface Mount
PT4205C = 3.3V/1.8A
PT4206C = 5V/1.2A
Mechanical Vibration
—
Per Mil-STD-202F, Method 204D,
10-500Hz, mounted to a PCB
—
10
—
G’s
Weight
—
—
—
—
—
20
—
—
—
grams
VDC
Isolation
—
1500
(For dimensions and PC
board layout, see Package
Style 900.)
Flammability
Materials meet UL 94V-0
** Minimum input voltage is adjustable - See application note.
60
Power Trends, Inc. 27715 Diehl Road, Warrenville, IL 60555 (800) 531-5782 Fax: (630) 393-6902 http://www.powertrends.com