DC/DC C
ONVERTERS
5
OR
28 V
OLT
I
NPUT
Features
•
•
•
•
•
•
•
•
•
–55°C to 100°C
5 or 28 VDC input
Fully isolated
Output regulated from input side
100 kHz typical switching frequency
Topology – Push-Pull DC/DC Converter
Up to 75% efficiency
No minimum load
Output capacitor suggested
MODELS
VDC O
UTPUT
SINGLES
DCH SERIES
3 WATT
NOT RECOMMENDED FOR NEW DESIGNS
DUALS
5
12
±12
±15
Size (max.):
Weight:
Screening:
0.975 x 0.800 x 0.350 inches (24.77 x 20.32 x 8.89 mm)
See case A3 for dimensions.
20 grams typical
Standard or ES. See “100°C Non-QML Products
– Environmental Screening (Standard & ES)” screening table for
screening options.
DESCRIPTION
The DCH Series™ offers isolated, unregulated DC/DC converters
with up to 3 watts of output power in a low profile (0.350 max.) metal
package. Single and dual output models are available with input volt-
ages of 5 or 28 VDC. DCH Series converters operate over a –55°C to
+100°C temperature range.
DCH Series converters use a non-saturating core circuit operating at
a frequency of approximately 100 kHz, which reduces reflected input
ripple and minimizes EMI/RFI problems. For applications requiring
MIL-STD-461C, CEO3, reflected input ripple levels, refer to Section B5
or contact your Interpoint representative for matching EMI filters.
Figure 1 shows a standard connection scheme for a dual output
model. Users may also elect to use a dual output device to provide a
single output at double the rated output voltage. The double voltage
connection is achieved by leaving the normal output common pin (Pin
15) unconnected and using either the positive or negative Vout pin for
the output common connection.
On all DCH Series models, a tantalum capacitor with a minimum
value of 22
μF
and an appropriate voltage rating should be connected
between the output common and the output line(s) to minimize output
ripple.
F
IGURE
1:
D
UAL
DCH C
ONVERTER
WITH
E
XTERNAL
C
APACITORS
Positive
Input
28 V
Positive
Output
Output Common
+
+
Load
Load
Input
Common
Negative
Output
Typical Performance Curves: 25°C Tc, nominal Vin
Efficiency
DCH2805S
F
IGURE
2
Output Current vs Output Voltage
DCH2805S
F
IGURE
3
1
CRANE [ Crane Aerospace & Electronics. ]
