A
6 Watt LV Single Series DC/DC Converters
2401 Stanwell Drive Concord, California 94520 Ph: 925/687-4411 or 800/542-3355 Fax: 925/687-3333 www.calex.com Email: sales@calex.com
6
3/2001
This example calculation is for an LV Single without any
extra heat sinking or appreciable air flow. Both of these factors
can greatly effect the maximum ambient temperature. Exact
efficiency depends on input line and load conditions, check
the efficiency curves for exact information.
This is a rough approximation to the maximum ambient
temperature. Because of the difficulty of defining ambient
temperature and the possibility that the loads dissipation may
actually increase the local ambient temperature significantly,
these calculations should be verified by actual measurement
before committing to a production design.
Remember, it is the system designers responsibility to be
sure that the case temperature of the LV Single does not
exceed 85°C for maximum reliability in operation.
0
10
2030
405060
7080
90
100
LOAD (%)
60
65
70
75
80
EFFICIENCY
(%)
EFFICIENCY Vs. LOAD
LINE = 5VDC
LINE = 16VDC
0
2
4
6
8
10
12
14
16
LINE INPUT (VOLTS)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
INPUT
CURRENT
(AMPS)
INPUT CURRENT Vs. LINE INPUT VOLTAGE
100% LOAD
50% LOAD
10
100
1000
10000
100000
1000000
FREQUENCY (Hz)
.01
.1
1
10
OUTPUT
IMPEDANCE
(OHMS)
OUTPUT IMPEDANCE Vs. FREQUENCY
5 VOLT OUTPUT
12/15 VOLT OUTPUT
4
6
8
1012
1416
LINE INPUT(VOLTS)
65
70
75
80
85
EFFICIENCY(%)
EFFICIENCY Vs. LINE INPUT VOLTAGE
100% FULL LOAD
50% FULL LOAD
3579
11
13
15
17
LINE INPUT (VDC)
0.0
0.2
0.4
0.6
0.8
1.0
RMS
INPUT
CURRENT
(AMPS)
RMS INPUT CURRENT Vs LINE INPUT
100% LOAD
75% LOAD
50% LOAD
Typical Performance (Tc=25°C, Vin=Nom VDC, Rated Load).
3.50
3.75
4.00
4.25
4.50
4.75
5.00
LINE INPUT (VDC)
0
20
40
60
80
100
120
%
AVAILABLE
POWER
LOW VOLTAGE POWER AVAILABLE