Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302
Tel 201-432-0463
Fax 201-432-9542
www.belfuse.com
Bus Converter
48V Input / 12V Output / 20A
Ideal for Intermediate Bus Architectures
Industry standard quarter-brick package
Up to 240W at 96% efficiency
1500V isolation
Remote on/off
Low cost
Safety Agency Approvals
Description
The 07CM-20S "Cimarron" Series are isolated DC/DC converters that operate from a nominal 48V source.
These converters are intended to provide isolation and step down to generate an intermediate bus for the
purpose of powering non-isolated Point-of-Load (POL) converters. These units will provide up to 240W of
output power from a nominal 48V input. These units are designed to be highly efficient and very low cost and
are thus unregulated. The downstream POL converters will provide the precise regulation required by the load.
Features include remote on/off, over current protection and undervoltage lockout. These converters are
provided in an industry standard quarter-brick package.
Part Selection
Output
Voltage
Input Voltage
Max. Output
Current
Max. Output
Power
Typical
Efficiency
Model Number
12V
48V
20A
240W
96%
07CM-20S12L
8V
48V
30A
240W
96%
07CM-30S08L
Change last character in part number from "0" to "H" for Active High On/Off Logic (e.g. 07CM-20S12H)
Input Specifications
Parameter
Min
Typ
Max
Notes
Input Voltage Range
36 VDC
55 VDC
Input Current (no load)
80mA
Input Current (full load)
5.3A
Reflected Ripple Current
(pk-pk)
50mA rms
100mA pk-pk
Reflected ripple current
through a 12uH source
inductor at nominal input
voltage and rated load
current.
Output Specifications
Parameter
Min
Typ
Max
Notes
Output Voltage
07CM-20S12x
07CM-30S08x
36V in
8.8V
5.8V
48V in
12.0V
8.0V
55Vin
14.0V
9.4V
Setpoint at no load.
Output Current
07CM-20S12x
07CM-30S08x
0A
0A
20A
30A
Load Regulation
5%
Ripple and Noise
100mV pk-pk
45mV rms
0 to 20MHz Bandwidth
Use 1.0uF ceramic cap and
15uF/100mOhm tantalum on
output
07CM-20S/30S Series PRELIMINARY
2003 Bel Fuse Inc. Specifications subject to change without notice. 011303
CORPORATE
FAR EAST
EUROPE
Bel Fuse Inc.
Bel Fuse Ltd.
Bel Fuse Europe Ltd.
206 Van Vorst Street
8F/ 8 Luk Hop Street
Preston Technology Management Centre
Jersey City, NJ 07302
San Po Kong
Marsh Lane, Suite G7, Preston
Tel 201-432-0463
Kowloon, Hong Kong
Lancashire, PR1 8UD, U.K.
Fax 201-432-9542
Tel 852-2328-5515
Tel 44-1772-556601
www.belfuse.com
Fax 852-2352-3706
Fax 44-1772-888366
www.belfuse.com
www.belfuse.com
Bus Converter
48V Input / 12V Output / 20A
Output Specifications (continued)
Parameter
Min
Typ
Max
Notes
Transient Response
Max deviation
Recovery to within 1%
200mV
50uS
350mV
100uS
di/dt =0 .1A/uS, Vin =48VDC
Ta = 25
C, 25% load change.
General Specifications
Parameter
Specification
Switching Frequency
120kHz typical (fixed)
Dimensions
inches
mm
2.28 x 1.45 x 0.50
57.9 x 36.8 x 12.7
Weight
42g (1.5oz)
Operating Temperature
0
C to 70
C
Non-Operating Temperature
-55
C to 125
C
MTBF (MIL-HDBK-217K)
>1,000,000 hours
Protection Features
Short circuit
Over current
Undervoltage
Continuous
120% to 140% max Io
UVLO Vin < 39.0
Remote On/Off
Active Low
(Optional Active High)
Low: 0V to 0.8V
High: 2.4V to 18V
Safety Agency Approvals
(pending)
UL / cUL Recognized
Certified to EN60950
Pin Connections
Pin
Function
1
+ Vin
2
Remote On/Off
3
- Vin
4
- Vout
5
+ Vout
1
2
3
+ Vin
on/off
- Vin
+ Vout
- Vout
5
4
2.28"
1.45"
Top View
60.00%
65.00%
70.00%
75.00%
80.00%
85.00%
90.00%
95.00%
100.00%
1
2.5
5
10
15
20
Efficiency vs. Output Current (A)
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