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2401 Stanwell Drive, Concord Ca. 94520 Ph: 925-687-4411 Fax: 925-687-3333 www.calex.com Email: sales@calex.com
ECO# 101028-1, 151005-3
100 WATT HEW SINGLE SERIES
DC/DC CONVERTERS
Features
4:1 Input voltage range
High power density
Small size 2.4” x 2.28” x 0.55”
Excellent thermal performance with metal baseplate
Volt-seconds clamp and fast over voltage protection
Pulse-by-pulse current limiting, short circuit frequency
foldback, dead short shut down
Over-temperature protection
Auto-softstart
Low noise
Industry-standard pinout
Constant frequency during normal operation
Remote sense
Remote ON/OFF
Super energy saving, 8 mA input idle current
Output trim with very low temperature coefcient
Water washable, wide humidity application
Good shock and vibration damping
Available in both RoHS and Non-RoHS construction.
See ordering info below model selection chart.
Selection Chart
Model
Input Range
VDC
Iin
ADC Vout
VDC
Iout
ADC
Min Max TYP
24S3.25HEW 9 36 4.24 3.3 25
24S5.20HEW 9 36 4.91 5 20
24S12.8HEW 9 36 4.85 12 8.33
24S15.7HEW 9 36 4.79 15 6.67
24S24.4HEW 9 36 4.79 24 4.13
48S3.25HEW 18 75 2.10 3.3 25
48S5.20HEW 18 75 2.42 5 20
48S12.8HEW 18 75 2.39 12 8.33
48S15.7HEW 18 75 2.37 15 6.67
48S24.4HEW 18 75 2.37 24 4.13
The 4:1 Input Voltage 100 W single HEW Series of DC/DC
converters provide precisely regulated dc outputs. The
output voltage is fully isolated from the input, allowing the
output to be positive or negative polarity and with various
ground connections. The HEW Series meets the most
rigorous performance standards in the industry standard
case size for data communications and process control
applications.
The 4:1 Input Voltage 100 Watt HEW Series includes
remote sensing, output trim, and remote ON/OFF.
Threaded-through holes are provided to allow easy
mounting or add a heat sink for extended temperature
use.
Description
Default ON/OFF logic is positive.
Add -N to the model number to order negative On/Off logic.
To order RoHS, add (RoHS) to part number.
A thermal management device, such as a heat sink is required to
ensure proper operation of this device. The thermal management
medium is required to maintain baseplate temperature < 100ºC
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2401 Stanwell Drive, Concord Ca. 94520 Ph: 925-687-4411 Fax: 925-687-3333 www.calex.com Email: sales@calex.com
ECO# 101028-1, 151005-3
100 WATT HEW SINGLE SERIES
DC/DC CONVERTERS
Input Parameters
Model 24S3.25HEW 24S5.20HEW 24S12.8HEW 24S15.7HEW 24S24.4HEW Units
Voltage Range
MIN
TYP
MAX
9
24
36
V
Input Overvoltage (100 ms) MAX 50 V
Input Ripple Rejection (120Hz) TYP 60 dB
Undervoltage Lockout Yes
Input Reverse Voltage Protection Yes
Input Current No Load
100% Load
TYP
TYP
35
4.24
35
4.91
35
4.85
35
4.79
35
4.79
mA
A
Inrush Current MAX 0.5 A2s
Reected Ripple, 12µH
Source Impedance (3) TYP 30 mA p-p
Efciency TYP 79 85 86 83 87 %
Switching Frequency TYP 260 kHz
Recommended Fuse (2) A
Input Parameters
Model 48S3.25HEW 48S5.20HEW 48S12.8HEW 48S15.7HEW 48S24.4HEW Units
Voltage Range
MIN
TYP
MAX
18
48
75
V
Input Overvoltage (100 mSec) MAX 80 V
Input Ripple Rejection (120Hz) TYP 60 dB
Undervoltage Lockout Yes
Input Reverse Voltage Protection Yes
Input Current No Load
100% Load
TYP
TYP
25
2.10
25
2.42
25
2.39
25
2.37
25
2.37
mA
A
Inrush Current MAX 0.5 A2s
Reected Ripple, 12µH
Source Impedance (3) TYP 30 mA p-p
Efciency TYP 81 85 88 88 89 %
Switching Frequency TYP 260 kHz
Recommended Fuse (2) A
Unless otherwise stated, these specications apply for baseplate temperature TB=23±2ºC, nominal input voltage, and rated full load. (1)
* Absolute Maximum Ratings. Caution: Stresses in excess of the Absolute Maximum Ratings can cause permanent damage to the device (see Note 1.)
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2401 Stanwell Drive, Concord Ca. 94520 Ph: 925-687-4411 Fax: 925-687-3333 www.calex.com Email: sales@calex.com
ECO# 101028-1, 151005-3
100 WATT HEW SINGLE SERIES
DC/DC CONVERTERS
Output Parameters
Model 24S3.25HEW
48S3.25HEW
24S5.20HEW
48S5.20HEW
24S12.8HEW
48S12.8HEW
24S15.7HEW
48S15.7HEW
24S24.4HEW
48S24.4HEW
Units
Output Voltage 3.3 5 12 15 24 V
Output Voltage
Setpoint Accuracy MAX ±1 %
Turn On Overshoot Min-Max Load TYP 0 %
Temperature Coefcient TYP
MAX
0.005
0.01
0.003
0.005
0.003
0.005
0.003
0.005
0.003
0.005 %/ºC
Noise (8) TYP
TYP
75
20
75
20
150
60
150
60
250
100
mV p-p
mV rms
Load Current (4) MIN
MAX
2.5
25
2
20
0.833
8.33
0.667
6.67
0.413
4.13 A
Load Transient Overshoot (7) TYP 3 %
Load Transient Recovery Time (6) TYP 200 µs
Load Regulation (5)
Min-Max Load
TYP
MAX
0.02
0.2 %
Line Regulation
Vin = Min-Max
TYP
MAX
0.01
0.1 %
Overvoltage Protection (OVP)
Threshhold
OVP Type - Non-latching
Open Loop Overvoltage Clamp
MIN
MAX
115
135 %
Output Current Limit
Vout = 90% of Vout-nom TYP 120 %
Output Short Circuit Current
Vout = 0.25V
TYP
MAX
140
150 %
Notes:
(1) Refer to the CALEX Application Notes for the denition of terms,
measurement circuits, and other information.
(2) Refer to the CALEX Application Notes for information of fusing.
For inrush current, refer to the specications above.
(3) 33µF capacitor connected between the two “Input” pins. Then
insert current sensor in series with 1.0µH inductor between
100µF and the source. The reected ripple current is measured
over a 5 Hz to 20 MHz bandwidth. (current sensor is located
between the converter input pin and the 1.0 µH inductor)
(4) Optimum performance is obtained when this power supply is
operated within the minimum to maximum load specications.
No damage to the module will occur when the output is operated
at less than minimum load, however, below minimum load the
dynamic response will degrade. Operation below minimum load
is not recommended.
(5) Load regulation is dened as the output voltage change when
changing load current from a maximum to minimum.
(6) Load Transient Recovery Time is dened as the time for the
output to settle from a 50% to 75% step load change to a 1%
error band (rise time of step = 2µs).
(7) Load Transient Overshoot is dened as the peak overshoot
during a transient as dened in the Note 6 above.
(8) Noise is measured per the CALEX Application Notes. Output
noise is measured with a 10µF tantalum capacitor in parallel with
a 0.1µF ceramic capacitor connected across the output pins.
Measurement bandwidth is 0-20MHz.
(9) When an external ON/OFF switch is used, such as open collector
switch, logic high requires the switch to be high-impedance.
Switch leakage currents greater than 10µA may be sufcient to
trigger the ON/OFF to the logic-low state.
(10) Most switches would be suitable for the logic ON/OFF control. In
case there is a problem you can make the following estimations and
then leave some margin.
When open collector is used for logic high, “Open Circuit Voltage at
ON/OFF Pin”, “Output Resistance” and “External Leakage Current
Allowed for Logic High” are used to estimate the high impedance
requirement of open collector.
When switch is used for logic low, “Open Circuit Voltage at ON/
OFF Pin”, “Output Resistance” and “LOW Logic Level” are used to
estimate the low impedance requirement of the switch.
(11) Thermal impedance is tested with the converter mounted vertically
and facing another printed circuit board 1/2 inch away. If converter
is mounted horizontally with no obstruction, thermal impedance is
approximately 8°C/W.
(12) Water Washability - Calex DC/DC converters are designed to
withstand most solder/wash processes. Careful attention should be
used when assessing the applicability in your specic manufacturing
process. Converters are not hermetically sealed.
(13) Torque fasteners into threaded mounting inserts at 12 in.lbs. or less.
Greater torque may result in damage to unit and void the warranty.
(14) Input impedance on these units needs to be kept to a minimum. The
9-36Vdc DC units need a maximum input impedance of 0.2 Ohms
and the 18-75Vdc DC units need a maximum input impedance of 0.8
Ohms. In order to support this requirement, the 9-36Vdc DC units
need 25 µF of capacitance (low ESR) for every 1.0 µH of inductance
between the power source and the DC/DC converter. The 18-75Vdc
DC units need 1.7µF of capacitance (low ESR) for every 1.0 µH of
inductance between the power source and the DC/DC converter.
Inductance includes all sources and should take into account input
power lines.
(15) RoHS Compliance:
See Calex Website www.calex.com/RoHS.html for the complete
RoHS Compliance statement.
The RoHS marking is as follows.
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2401 Stanwell Drive, Concord Ca. 94520 Ph: 925-687-4411 Fax: 925-687-3333 www.calex.com Email: sales@calex.com
ECO# 101028-1, 151005-3
100 WATT HEW SINGLE SERIES
DC/DC CONVERTERS
General Specications
All Models Units
ON/OFF Function
HIGH Logic Level or
Leave ON/OFF Pin Open MIN 3.0 VDC
External Leakage Current
Allowed for Logic High (9) MAX 10 µA
Input Diode Protection
Voltage MAX 50 VDC
LOW Logic Level or
Tie ON/OFF Pin to -INPUT MAX 1.0 VDC
Sinking Current for Logic
Low MAX 500 µA
Open Circuit Voltage at
ON/OFF Pin (10)
Positive Logic
Negative Logic
TYP
TYP
2.3
1.5
VDC
VDC
Output Resistance TYP 3 k Ω
Idle Current
(Module is OFF) TYP 8 mADC
Turn-on Time to 1% error TYP 60 ms
Positive Logic Option HIGH - Module ON
LOW - Module OFF
Negative Logic Option HIGH - Module OFF
LOW - Module ON
Output Voltage Remote Sensing
Maximum Voltage Drops
on Leads MAX 10 %
Line Regulation under
remote sensing
TYP
MAX
0.02
0.1 %
Load Regulation under
remote sensing
TYP
MAX
0.05
0.2 %
Output Voltage Trim
Trim Range MIN
MAX
-10
+10 % of Vout
Input Resistance TYP 10
Open Circuit Voltage TYP 2.5 V
Trim Limit
Maximum Output Voltage MAX 110 % of Vout
Isolation
Input to Output Isolation
10µA Leakage
Vnom = 24V
Vnom = 48V
MAX
MAX
700
1544
VDC
VDC
Input to Output Resistance MIN 10
Input to Output
Capacitance TYP 1600 pF
Environmental
Calculated MTBF, Bellcore
Method 1, Case 1 >1,000,000 h
Baseplate Operating
Temperature Range
MIN
MAX
-40
100 ºC
Storage Temperature MIN
MAX
-40
120 ºC
Thermal Impedance (11) TYP 7 ºC/W
Thermal Shutdown
Baseplate
Temperature (Auto Restart)
MIN
TYP
100
110 ºC
Pin Name 24Vin
Pin Dia.
48Vin
Pin Dia.
1 -INPUT 0.08” 0.04”
2 CASE 0.04” 0.04”
3 ON/OFF 0.04” 0.04”
4 +INPUT 0.08” 0.04”
5 -OUTPUT 0.08” 0.08”
6 -SENSE 0.04” 0.04”
7 TRIM 0.04” 0.04”
8 + SENSE 0.04” 0.04”
9 + OUTPUT 0.08” 0.08”
TOLERANCE: ALL DIMENSIONS ARE TYPICAL IN
INCHES UNLESS OTHERWISE NOTED:
X.XX ±0.020
X.XXX ±0.005
General Specications
All Models Units
General
Unit Weight TYP 4.6/114 oz/g
Case Dimension 2.4” x 2.28” x 0.55”
Torque on Mounting Inserts MAX 12 in. lbs.
Agency Approvals
UL IEC 60950-1, EN60950-1
Chassis Mounting Kit MS21