GE
Datasheet
March 13, 2014 ©2014 General Electric Corporation. All rights reserved. Page 1
EHHD024A0A HAMMERHEAD* Series; DC-DC Converter Power Modules
18-75Vdc Input; 5Vdc, 24A, 120W Output
Features
Compliant to RoHS II EU “Directive 2011/65/EU (-Z versions)
Compliant to REACH Directive (EC) No 1907/2006
Flat and high efficiency curve
Industry standard, DOSA compliant footprint
58.4mm x 22.8mm x 8.9mm
(2.30 in x 0.9 in x 0.35 in)
Ultra wide input voltage range: 18-75 V
dc
Tightly regulated output
Remote sense
Output Voltage adjust: 90% to 110% of V
O,nom
Constant switching frequency
Positive remote On/Off logic
Output overcurrent and overvoltage protection
Overtemperature protection
Wide operating temperature range (-40°C to 85°C)
Suitable for cold wall cooling using suitable Gap Pad applied
directly to top side of module
ANSI/UL
#
60950-1-2011 and CAN/CSA† C22.2 No. 60950-1-
07, Second Edition + A1:2011 (MOD), dated March 19, 2011;
and DIN EN 60950-1 (VDE‡ 0805 Teil 1):2011-01; EN 60950-
1:2006 + A11:2009 + A1:2010, DIN EN 60950-1/A12 (VDE
0805-1/A12):2011-08; EN 60950-1/A12:2011-02, IEC 60950-
1(ed.2);am1:2009
CE mark meets 2006/95/EC directive
§
Meets the voltage and current requirements for ETSI 300-
132-2 and complies with and licensed for Basic insulation
rating per EN60950-1
2250 Vdc Isolation tested in compliance with IEEE 802.3
¤
PoE
standards
ISO
**
9001 and ISO 14001 certified manufacturing facilities
Applications
Distributed Power Architectures
Wireless Networks
Enterprise Networks including Power over Ethernet (PoE)
Industrial Equipment
Options
Negative Remote On/Off logic (preferred)
Over current/Over temperature/Over voltage protections
(Auto-restart) (preferred)
1/8
th
Brick Heat plate for 1/8
th
heatsinks
1/4
th
Brick heat plate with unthreaded inserts
Surface Mount version (-S)
Description
The EHHD024A0A [HAMMERHEAD*] Series, eighth-brick, low-height power modules are isolated dc-dc converters which provide a
single, precisely regulated output voltage over an ultra-wide input voltage range of 18-75V
dc
. The EHHD024A0A provides 5V
dc
nominal output voltage rated for 24A
dc
output current. The module incorporates GE’s vast heritage for reliability and quality, while
also using the latest in technology, and component and process standardization to achieve highly competitive cost. The open
frame module construction, available in both surface-mount and through-hole packaging, enable designers to develop cost and
space efficient solutions. The module achieves typical full load efficiency greater than 91% at V
IN
=24V
dc
and V
IN
=48V
dc
. Standard
features include remote On/Off, remote sense, output voltage adjustment, overvoltage, overcurrent and overtemperature
protection. An optional heat plate allows for external standard, eighth-brick or quarter-brickheat sink attachment to achieve
higher output current in high temperature applications.
*
Trademark of General Electric Corporation.
#
UL is a registered trademark of Underwriters Laboratories, Inc.
†
CSA is a registered trademark of Canadian Standards Association.
‡
VDE is a trademark of Verband Deutscher Elektrotechniker e.V.
§ This product is intended for integration into end-user equipment . All of the required procedures of end-use equipment should be followed.
¤ IEEE and 802 are registered trademarks of the Institute of Electrical and Electronics Engineers, Incorporated.
** ISO is a registered trademark of the International Organization of Standards
RoHS Compliant
GE Datasheet
EHHD024A0A Series: DC-DC Converter Power Module
18 to 75Vdc Input; 5Vdc, 24A, 120W Output
March 13, 2014 ©2014 General Electric Corporation. All rights reserved. Page 2
Absolute Maximum Ratings
Stresses in excess of the absolute maximum ratings can cause permanent damage to the device. These are absolute stress ratings
only, functional operation of the device is not implied at these or any other conditions in excess of those given in the operations
sections of the data sheet. Exposure to absolute maximum ratings for extended periods can adversely affect the device reliability.
Parameter Device Symbol Min Max Unit
Input Voltage
Continuous All VIN -0.3 80 Vdc
Transient, operational (100 ms) All VIN,trans -0.3 100 Vdc
Operating Ambient Temperature All TA -40 85 °C
Maximum Heat Plate Operating Temperature -18H, H TC -40 105 °C
(see Thermal Considerations section)
Storage Temperature All Tstg -55 125 °C
Altitude* All 4000 m
I/O Isolation voltage (100% factory Hi-Pot tested) All 2250 Vdc
* For higher altitude applications, contact your GE Sales Representative for alternative conditions of use.
Electrical Specifications
Unless otherwise indicated, specifications apply over all operating input voltage, resistive load, and temperature conditions.
Parameter Device Symbol Min Typ Max Unit
Operating Input Voltage All VIN 18 24/48 75 Vdc
Maximum Input Current All IIN 7.3 7.8 Adc
(VIN= VIN, min to VIN, max, VO= VO, set, IO=IO, max)
Input No Load Current
All IIN,No load
120
80
mA
VIN = 24Vdc, (IO = 0, module enabled)
VIN = 48V, (IO = 0, module enabled)
Input Stand-by Current All IIN,stand-by 5 11 mA
(VIN = 24 to 48V, module disabled)
Inrush Transient All I2t 0.5 A2s
Input Reflected Ripple Current, peak-to-peak
(5Hz to 20MHz, 12ƄH source impedance; VIN, min to VIN, max, IO= IOmax ;
See Test configuration section)
All 30 mAp-p
Input Ripple Rejection (120Hz) All 60 dB
CAUTION: This power module is not internally fused. An input line fuse must always be used.
This power module can be used in a wide variety of applications, ranging from simple standalone operation to an integrated part
of sophisticated power architectures. To preserve maximum flexibility, internal fusing is not included, however, to achieve
maximum safety and system protection, always use an input line fuse. The safety agencies require a fast-acting fuse with a
maximum rating of 15 A (see Safety Considerations section). Based on the information provided in this data sheet on inrush energy
and maximum dc input current, the same type of fuse with a lower rating can be used. Refer to the fuse manufacturer’s data sheet
for further information.
GE Datasheet
EHHD024A0A Series: DC-DC Converter Power Module
18 to 75Vdc Input; 5Vdc, 24A, 120W Output
March 13, 2014 ©2014 General Electric Corporation. All rights reserved. Page 3
Electrical Specifications (continued)
Unless otherwise indicated, specifications apply at VIN = 48Vdc, resistive load, and TA = 25°C conditions.
Parameter Device Symbol Min Typ Max Unit
Nominal Output Voltage Set-point All VO, set 4.93 5 5.07 Vdc
VIN= 24V to 48V IO=IO, max, TA=25°C)
Output Voltage
All VO -3.0 +3.0 % VO, set
(Over all operating input voltage, resistive load, and temperature
conditions until end of life)
Adjustment Range (*Vin > 20V) All VO, adj -10 +10* % VO, set
Selected by external resistor
Output Regulation
Line (VIN=VIN, min to VIN, max) All ±0.2 % VO, set
Load (IO=IO, min to IO, max) All ±0.2 % VO, set
Temperature (Tref=TA, min to TA, max) All ±1.5 % VO, set
Output Ripple and Noise on nominal output
Measured with 10uF Tantalum||1uF ceramic
(VIN=24 to 48, IO=80% IO, max , TA=25)
RMS (5Hz to 20MHz bandwidth) All 30 mVrms
Peak-to-Peak (5Hz to 20MHz bandwidth) All 100 mVpk-pk
External Capacitance All CO, max 0 10,000 ƄF
Output Current All IO 0 24 Adc
Output Current Limit Inception (Hiccup Mode )
(VO= 90% of VO, set) 5 IO, lim 26.5 29 Adc
Output Short-Circuit Current All IO, s/c 1.2 Arms
(VO250mV) ( Hiccup Mode )
Efficiency
VIN=24V, TA=25°C, IO=24A, VO = 5V All ſ 92 %
VIN=48V, TA=25°C, IO=24A, VO = 5V All ſ 91.5 %
Switching Frequency All fsw 280 kHz
Dynamic Load Response
(dIo/dt=0.1A/µs; VIN = 24V or 48V; TA=25°C; CO>100ƄF)
Load Change from Io= 50% to 75% or 25% to 50% of Io,max
Peak Deviation All Vpk 3 % VO, set
Settling Time (Vo<10% peak deviation) All ts 800 µs
Isolation Specifications
Parameter Device Symbol Min Typ Max Unit
Isolation Capacitance All Ciso 1000 pF
Isolation Resistance All Riso 10 Mű
I/O Isolation Voltage (100% factory Hi-pot tested) All All 2250 Vdc
General Specifications
Parameter Device Symbol Min Typ Max Unit
Calculated Reliability based upon Telcordia SR-332 Issue 2: Method I
Case 3 (IO=80%IO, max, TA=40°C, airflow = 200 lfm, 90% confidence)
All FIT 112.7 109/Hour
s
All MTBF 8,869,389 Hours
Weight (Open Frame) All 23(0.8) g (oz.)
Weight (with Heatplate) All 37(1.3) g (oz.)
GE Datasheet
EHHD024A0A Series: DC-DC Converter Power Module
18 to 75Vdc Input; 5Vdc, 24A, 120W Output
March 13, 2014 ©2014 General Electric Corporation. All rights reserved. Page 4
Feature Specifications
Unless otherwise indicated, specifications apply over all operating input voltage, resistive load, and temperature conditions. See
Feature Descriptions for additional information.
Parameter Device Symbol Min Typ Max Unit
Remote On/Off Signal Interface
(VIN=VIN, min to VIN, max ; open collector or equivalent,
Signal referenced to VIN- terminal)
Negative Logic: device code suffix “1”
Logic Low = module On, Logic High = module Off
Positive Logic: No device code suffix required
Logic Low = module Off, Logic High = module On
Logic Low - Remote On/Off Current All Ion/off 0.15 mA
Logic Low - On/Off Voltage All Von/off -0.7 0.6 Vdc
Logic High Voltage – (Typ = Open Collector) All Von/off 2.5 5 6.7 Vdc
Logic High maximum allowable leakage current All Ion/off 20 ƄA
Turn-On Delay and Rise Times
(IO=IO, max , VIN=VIN, nom, TA = 25oC)
Case 1: Input power is applied for at least 1 second,
and then the On/Off input is set from OFF to ON
(Tdelay = on/off pin transition until VO = 10% of VO, set)
All Tdelay — 35 — msec
Case 2: On/Off input is set to Logic Low (Module
ON) and then input power is applied (Tdelay from
instant at which VIN = VIN, min until Vo=10% of VO,set)
All Tdelay — 35 - msec
Output voltage Rise time (time for Vo to rise from 10%
of Vo,set to 90% of Vo, set) All Trise — 20 msec
Output voltage overshoot – Startup All — 3 % VO, set
IO= IO, max; VIN=VIN, min to VIN, max, TA = 25 oC
Remote Sense Range All VSENSE 10 % VO, set
Output Overvoltage Protection1 All VO, limit 5.9 7.0 Vdc
Overtemperature Protection – Hiccup Auto Restart
Open
frame Tref 135 OC
Heat
Plate Tref 120 OC
Input Undervoltage Lockout All VUVLO
Turn-on Threshold 17.5 Vdc
Turn-off Threshold 15 15.5 Vdc
Hysteresis 1 2 Vdc
Input Overvoltage Lockout All VOVLO
Turn-on Threshold 76 79 Vdc
Turn-off Threshold 81 Vdc
Hysteresis 1 2 Vdc
1 – Module complies with 7Vmax with Trim Pin short to Sense+, with and without external cap. For Open Loop condition max OVP was 7.3V with min. 220µF external cap
GE
Datasheet
EHHD024A0A Series: DC-DC Converter Power Module
18 to 75V
dc
Input; 5V
dc
, 24A, 120W Output
March 13, 2014 ©2014 General Electric Corporation. All rights reserved. Page 5
Characteristic Curves
The following figures provide typical characteristics for the EHHD024A0A (5V, 24A) at 25
O
C. The figures are identical for either
positive or negative remote On/Off logic.
EFFICIENCY, η (%)
OUTPUT CURRENT OUTPUT VOLTAGE
Io(A) (5A/div) V
O
(V) (200mV/div)
OUTPUT CURRENT, I
O
(A) TIME, t (200µs/div)
Figure 1. Converter Efficiency versus Output Current.
Figure 4. Transient Response to 0.1A/µS Dynamic Load Change
from 50% to 75% to 50% of full load, Vin=48V.
OUTPUT VOLTAGE
V
O
(V) (50mV/div)
OUTPUT VOLTAGE On/Off VOLTAGE
V
O
(V) (2V/div) V
On/Off
(V) (5V/div)
TIME, t (2µs/div) TIME, t (10ms/div)
Figure 2. Typical output ripple and noise (I
o
= I
o,max
). Figure 5. Typical Start-up Using Remote On/Off, negative logic
version shown (V
IN
= 48V, I
o
= I
o,max
).
OUTPUT CURRENT OUTPUT VOLTAGE
Io(A) (5A/div) V
O
(V) (200mV/div)
OUTPUT VOLTAGE INPUT VOLTAGE
V
O
(V) (2V/div) V
IN
(V) (20V/div)
TIME, t (200µs/div) TIME, t (10ms/div)
Figure 3. Transient Response to 0.1A/µS
Dynamic Load
Change from 50% to 75% to 50% of full load, Vin=24V
Figure 6. Typical Start-up Using Input Voltage (V
IN
= 48V, I
o
=
I
o,max
).
70
75
80
85
90
95
0 4 8 12 16 20 24
Vin=75V
Vin=18V
Vin=24V
Vin=36V Vin=48V
48
V
in
75
V
in
18
V
in
24
V
in
GE Datasheet
EHHD024A0A Series: DC-DC Converter Power Module
18 to 75Vdc Input; 5Vdc, 24A, 120W Output
March 13, 2014 ©2014 General Electric Corporation. All rights reserved. Page 6
Test Configurations
TO OSCILLOSCOPE CURRENT PROBE
LTES T
12ȝH
BATTERY
CS 220ȝF
E.S.R.<0.1Ω
@ 20°C 100kHz
33-100ȝF
Vin+
Vin-
NOTE: Measure input reflected ripple current with a simulated
source inductance (LTEST) of 12ȝH. Capacitor CS offsets
possible battery impedance. Measure current as shown
above.
Figure 7. Input Reflected Ripple Current Test Setup.
NOTE: All voltage measurem ents to be taken at the module
terminals, as sho wn above. If sockets are used then
Kelvin connections are requ ired at the module terminals
to avoid measurement errors due to socket contact
resista nce.
V
O (+)
V
O
( – )
RESISTIVE
LOA D
SCOPE
COPPER STRIP
GROUND PLANE
10uF
1uF
Figure 8. Output Ripple and Noise Test Setup.
Vout+
Vout-
Vin+
Vin-
RLOAD
Rcontact Rdistribution
Rcontact Rdistribution
Rcontact
Rcontact
Rdistribution
Rdistribution
VIN VO
NOTE: All voltage measurements to be taken at the module
terminals, as shown above. If sockets are used then
Kelvin connections are required at the module terminals
to avoid measurement errors due to socket contact
resistance.
Figure 9. Output Voltage and Efficiency Test Setup.
η =
VO. IO
VIN. IIN
x 100 %
Efficiency
Design Considerations
Input Filtering
The power module should be connected to a low
ac-impedance source. Highly inductive source impedance
can affect the stability of the power module. For the test
configuration in Figure 7 a 100ƄF electrolytic capacitor
(ESR<0.7Ω at 100kHz), mounted close to the power module
helps ensure the stability of the unit. Consult the factory for
further application guidelines.
Safety Considerations
For safety-agency approval of the system in which the
power module is used, the power module must be installed
in compliance with the spacing and separation
requirements of the end-use safety agency standard, i.e.
UL60950-1, CSA C22.2 No.60950-1, and VDE0805-
1(IEC60950-1).
If the input source is non-SELV (ELV or a hazardous voltage
greater than 60 Vdc and less than or equal to 75Vdc), for the
module’s output to be considered as meeting the
requirements for safety extra-low voltage (SELV), all of the
following must be true:
The input source is to be provided with reinforced
insulation from any other hazardous voltages, including
the ac mains.
One VIN pin and one VOUT pin are to be grounded, or
both the input and output pins are to be kept floating.
The input pins of the module are not operator
accessible.
Another SELV reliability test is conducted on the whole
system (combination of supply source and subject
module), as required by the safety agencies, to verify
that under a single fault, hazardous voltages do not
appear at the module’s output.
Note: Do not ground either of the input pins of the module
without grounding one of the output pins. This may
allow a non-SELV voltage to appear between the
output pins and ground.
The power module has extra-low voltage (ELV) outputs when
all inputs are ELV.
All flammable materials used in the manufacturing of these
modules are rated 94V-0, or tested to the UL60950 A.2 for
reduced thickness.
For input voltages exceeding –60 Vdc but less than or equal
to –75 Vdc, these converters have been evaluated to the
applicable requirements of BASIC INSULATION between
secondary DC MAINS DISTRIBUTION input (classified as
TNV-2 in Europe) and unearthed SELV outputs.
The input to these units is to be provided with a maximum
15 A fast-acting fuse in the ungrounded lead.
GE Datasheet
EHHD024A0A Series: DC-DC Converter Power Module
18 to 75Vdc Input; 5Vdc, 24A, 120W Output
March 13, 2014 ©2014 General Electric Corporation. All rights reserved. Page 7
Feature Descriptions
Remote On/Off
Two remote on/off options are available. Positive logic turns
the module on during a logic high voltage on the ON/OFF
pin, and off during a logic low. Negative logic remote On/Off,
device code suffix “1”, turns the module off during a logic
high and on during a logic low.
ON/OFF
Vin+
Vin-
Ion/off
Von/off
Vout+
TRIM
Vout-
Figure 10. Remote On/Off Implementation.
To turn the power module on and off, the user must supply a
switch (open collector or equivalent) to control the voltage
(Von/off) between the ON/OFF terminal and the VIN(-) terminal
(see Figure 10). Logic low is 0V Von/off 0.6V. The maximum
Ion/off during a logic low is 0.15mA; the switch should
maintain a logic low level whilst sinking this current.
During a logic high, the typical maximum Von/off generated
by the module is 5V, and the maximum allowable leakage
current at Von/off = 5V is 1ƄA.
If not using the remote on/off feature:
For positive logic, leave the ON/OFF pin open.
For negative logic, short the ON/OFF pin to VIN(-).
Remote Sense
Remote sense minimizes the effects of distribution losses by
regulating the voltage at the remote-sense connections (See
Figure 11). The voltage between the remote-sense pins and
the output terminals must not exceed the output voltage
sense range given in the Feature Specifications table:
[VO(+) – VO(–)] – [SENSE(+) – SENSE(–)] ≤ 0.5 V
Although the output voltage can be increased by both the
remote sense and by the trim, the maximum increase for
the output voltage is not the sum of both. The maximum
increase is the larger of either the remote sense or the trim.
The amount of power delivered by the module is defined as
the voltage at the output terminals multiplied by the output
current. When using remote sense and trim, the output
voltage of the module can be increased, which at the same
output current would increase the power output of the
module. Care should be taken to ensure that the maximum
output power of the module remains at or below the
maximum rated power (Maximum rated power = Vo,set x
Io,max).
Figure 11. Circuit Configuration for remote sense .
Input Undervoltage Lockout
At input voltages below the input undervoltage lockout limit,
the module operation is disabled. The module will only
begin to operate once the input voltage is raised above the
undervoltage lockout turn-on threshold, VUV/ON.
Once operating, the module will continue to operate until
the input voltage is taken below the undervoltage turn-off
threshold, VUV/OFF.
Overtemperature Protection
To provide protection under certain fault conditions, the unit
is equipped with a thermal shutdown circuit. The unit will
shutdown if the thermal reference point, Tref, exceeds 120°
and 124 OC (Figure 13, typical) or 105 OC (Figure 14, typical),
but the thermal shutdown is not intended as a guarantee
that the unit will survive temperatures beyond its rating.
The module will automatically restart upon cool-down to a
safe temperature.
Output Overvoltage Protection
The output over voltage protection scheme of the modules
has an independent over voltage loop to prevent single
point of failure. This protection feature latches in the event
of over voltage across the output. Cycling the on/off pin or
input voltage resets the latching protection feature. If the
auto-restart option (4) is ordered, the module will
automatically restart upon an internally programmed time
elapsing.
Overcurrent Protection
To provide protection in a fault (output overload) condition,
the unit is equipped with internal
current-limiting circuitry and can endure current
limiting continuously. At the point of current-limit
inception, the unit enters hiccup mode. If the unit is
not configured with auto–restart, then it will latch off
following the over current condition. The module can be
restarted by cycling the dc input power for at least one
second or by toggling the remote on/off signal for at least
one second.
VO(+)
SENSE(+)
SENSE(–)
VO(–)
VI(+)
VI(-)
IOLOAD
CONTACT AND
DISTRIBUTION LOSS
E
SUPPLY II
CONTACT
RESISTANCE
GE Datasheet
EHHD024A0A Series: DC-DC Converter Power Module
18 to 75Vdc Input; 5Vdc, 24A, 120W Output
March 13, 2014 ©2014 General Electric Corporation. All rights reserved. Page 8
Feature Descriptions (continued)
If the unit is configured with the auto-restart option (4), it will
remain in the hiccup mode as long as the overcurrent
condition exists; it operates normally, once the output
current is brought back into its specified range. The average
output current during hiccup is 10% IO, max.
Output Voltage Programming
Trimming allows the output voltage set point to be
increased or decreased from the default value; this is
accomplished by connecting an external resistor between
the TRIM pin and either the VO(+) pin or the VO(-) pin.
VO(+)
VOTRIM
VO(-)
Rtrim-down
LOAD
VIN(+)
ON/OFF
VIN(-)
Rtrim-up
Figure 12. Circuit Configuration to Trim Output Voltage.
Connecting an external resistor (Rtrim-down) between the TRIM
pin and the VO(-) (or Sense(-)) pin decreases the output
voltage set point. To maintain set point accuracy, the trim
resistor tolerance should be ±1.0%.
The following equation determines the required external
resistor value to obtain a percentage output voltage change
of ŝ%
ΚΩ
»
¼
º
«
¬
ª−
∆
=
−22.10
%
511
downtrim
R
Where 100
0.5
0.5
%×
¸
¹
·
¨
©
§−
=∆ V
VV desired
For example, to trim-down the output voltage of the module
by 6% to 4.7V, Rtrim-down is calculated as follows:
6% =∆
ΚΩ
»
¼
º
«
¬
ª−=
−22.10
6
511
downtrim
R
ΚΩ=
−9.74
downtrim
R
Connecting an external resistor (Rtrim-up) between the TRIM
pin and the VO(+) (or Sense (+)) pin increases the output
voltage set point. The following equation determines the
required external resistor value to obtain a percentage
output voltage change of ŝ%:
ΚΩ
»
¼
º
«
¬
ª−
∆
−
∆×
∆+××
=
−22.10
%
511
%225.1
%)100(0.511.5
uptrim
R
Where 100
0.5
0.5
%×
¸
¹
·
¨
©
§−
=∆ desired
V
For example, to trim-up the output voltage of the module by
4% to 5.2V, Rtrim-up is calculated is as follows:
4% =∆
ΚΩ
»
¼
º
«
¬
ª−−
×
+××
=
−22.10
4
511
4225.1
)4100(0.511.5
uptrim
R
ΚΩ=
−3.404
uptrim
R
The voltage between the VO(+) and VO(–) terminals must not
exceed the minimum output overvoltage protection value
shown in the Feature Specifications table. This limit includes
any increase in voltage due to remote-sense compensation
and output voltage set-point adjustment trim.
Although the output voltage can be increased by both the
remote sense and by the trim, the maximum increase for
the output voltage is not the sum of both. The maximum
increase is the larger of either the remote sense or the trim.
The amount of power delivered by the module is defined as
the voltage at the output terminals multiplied by the output
current. When using remote sense and trim, the output
voltage of the module can be increased, which at the same
output current would increase the power output of the
module. Care should be taken to ensure that the maximum
output power of the module remains at or below the
maximum rated power (Maximum rated power = VO,set x
IO,max).
Thermal Considerations
The power modules operate in a variety of thermal
environments; however, sufficient cooling should be
provided to help ensure reliable operation.
Considerations include ambient temperature, airflow,
module power dissipation, and the need for increased
reliability. A reduction in the operating temperature of the
module will result in an increase in reliability.
The thermal data presented here is based on physical
measurements taken in a wind tunnel, using automated
thermo-couple instrumentation to monitor key component
temperatures: FETs, diodes, control ICs, magnetic cores,
ceramic capacitors, opto-isolators, and module pwb
conductors, while controlling the ambient airflow rate and
temperature. For a given airflow and ambient temperature,
the module output power is increased, until one (or more) of
the components reaches its maximum derated operating
temperature, as defined in IPC-9592. This procedure is then
repeated for a different airflow or ambient temperature until
a family of module output derating curves is obtained.
GE
Datasheet
EHHD024A0A Series: DC-DC Converter Power Module
18 to 75V
dc
Input; 5V
dc
, 24A, 120W Output
March 13, 2014 ©2014 General Electric Corporation. All rights reserved. Page 9
Thermal Considerations (continued)
The thermal reference points, T
ref1
,
& T
ref2
, used in the
specifications for open frame modules are shown in Figure
13. For reliable operation these temperatures should not
exceed 120
O
C and 124
O
C
Figure 13. T
ref
Temperature Measurement Locations for
Open Frame Module.
The thermal reference point, T
ref
,
used in the specifications
for modules with heatplate is shown in Figure 14. For
reliable operation this temperature should not exceed 98
O
C.
Figure 14. T
ref
Temperature Measurement Location for
Module with Heat plate.
Heat Transfer via Convection
Increased airflow over the module enhances the heat
transfer via convection. Derating curves showing the
maximum output current that can be delivered by
each module versus local ambient temperature (T
A
)
for natural convection and up to 3m/s (600 ft./min) forced
airflow are shown in Figures 15 - 21.
Please refer to the Application Note “Thermal
Characterization Process For Open-Frame Board-Mounted
Power Modules” for a detailed discussion of thermal
aspects including maximum device temperatures.
OUTPUT CURRENT, I
O
(A)
AMBIENT TEMEPERATURE, T
A
(
o
C
)
Figure 15. Output Current Derating for the Open Frame
Module; Airflow in the Transverse Direction from V
out
(-) to
V
out
(+); V
IN
=48V, V
O
=5V.
OUTPUT CURRENT, I
O
(A)
AMBIENT TEMEPERATURE, T
A
(
o
C
)
Figure 16. Output Current Derating for the Module with
Heatplate; Airflow in the Transverse Direction from V
out
(-)
to V
out
(+);V
IN
=48V, V
O
=5V.
T
ref
1
T
ref
2
AIRFLOW
0
4
8
12
16
20
24
25 35 45 55 65 75 85
NC
100LFM
(0.5m/s)
200LFM
(1.0m/s) 400LFM
(2.0m/s)
600LFM
(3.0m/s)
0
4
8
12
16
20
24
25 35 45 55 65 75 85
NC
100LFM
(0.5m/s) 200LFM
(1.0m/s)
400LFM
(2.0m/s)
GE Datasheet
EHHD024A0A Series: DC-DC Converter Power Module
18 to 75Vdc Input; 5Vdc, 24A, 120W Output
March 13, 2014 ©2014 General Electric Corporation. All rights reserved. Page 10
Thermal Considerations (continued)
OUTPUT CURRENT, IO (A)
AMBIENT TEMEPERATURE, TA (oC)
Figure 17. Output Current Derating for the Module with
-18H Heatplate; Airflow in the Transverse Direction from
Vout(-) to Vout(+);VIN =48V, VO=5V
OUTPUT CURRENT, IO (A)
AMBIENT TEMEPERATURE, TA (oC)
Figure 18. Output Current Derating for the Open Frame
Module; Airflow in the Transverse Direction from Vout(-) to
Vout(+); VIN =24V, VO=5V.
OUTPUT CURRENT, IO (A)
AMBIENT TEMEPERATURE, TA (oC)
Figure 19. Output Current Derating for the Module with
Heatplate; Airflow in the Transverse Direction from Vout(-)
to Vout(+);VIN =24V, VO=5V.
OUTPUT CURRENT, IO (A)
AMBIENT TEMEPERATURE, TA (oC)
Figure 20. Output Current Derating for the Module with
-18 Heatplate; Airflow in the Transverse Direction from
Vout(-) to Vout(+);VIN =24V, VO=5V.
Heat Transfer via Conduction
The module can also be used in a sealed environment with
cooling via conduction from the
module’s top surface through a gap pad material to a
cold wall, as shown in Figure 22. This capability is achieved
by insuring the top side component skyline profile achieves
no more than 1mm height difference between the tallest
and the shortest power train part that benefits from contact
with the gap pad material. The output current derating
versus cold wall temperature, when using a gap pad such as
Bergquist GP2500S20, is shown in Figure 21.
Figure 21. Cold Wall Mounting
OUTPUT CURRENT, IO (A)
COLDPLATE TEMEPERATURE, TC (oC)
Figure 22. Derated Output Current versus Cold Wall
Temperature with local ambient temperature around
module at 85C; VIN =24V or 48V.
0
4
8
12
16
20
24
25 35 45 55 65 75 85
NC
100LFM
(0.5m/s)
200LFM
(1.0m/s) 400LFM
(2.0m/s)
0
4
8
12
16
20
24
25 35 45 55 65 75 85
NC
100LFM
(0.5m/s)
200LFM
(1.0m/s)
400LFM
(2.0m/s)
0
4
8
12
16
20
24
25 35 45 55 65 75 85
NC
100LFM
(0.5m/s)
200LFM
(1.0m/s) 400LFM
(2.0m/s)
0
4
8
12
16
20
24
25 35 45 55 65 75 85
NC
100LFM
(0.5m/s)
200LFM
(1.0m/s)
400LFM
(2.0m/s)
0
4
8
12
16
20
24
20 30 40 50 60 70 80 90
GE Datasheet
EHHD024A0A Series: DC-DC Converter Power Module
18 to 75Vdc Input; 5Vdc, 24A, 120W Output
March 13, 2014 ©2014 General Electric Corporation. All rights reserved. Page 11
Through-Hole Soldering Information
Lead-Free Soldering
The EHHD024A0A xx RoHS-compliant through-hole
products use SAC (Sn/Ag/Cu) Pb-free solder and RoHS-
compliant components. They are designed to be processed
through single or dual wave soldering machines. The pins
have a RoHS-compliant finish that is compatible with both
Pb and Pb-free wave soldering processes. A maximum
preheat rate of 3°C/s is suggested. The wave preheat
process should be such that the temperature of the power
module board is kept below 210°C. For Pb solder, the
recommended pot temperature is 260°C, while the Pb-free
solder pot is 270°C max.
Paste-in-Hole Soldering
The EHHD024A0A xx module is compatible with reflow
paste-in-hole soldering processes shown in Figures 24-26.
Since the EHHD024A0A xxZ module is not packaged per J-
STD-033 Rev.A, the module must be baked prior to the
paste-in-hole reflow process. EHHD024A0A xx-HZ modules
are not compatible with paste-in-hole reflow soldering.
Please contact your GE Sales Representative for further
information.
Surface Mount Information
MSL Rating
The EHHD024A0A -SZ module has a MSL rating of 2a.
Storage and Handling
The recommended storage environment and handling
procedures for moisture-sensitive surface mount packages
is detailed in J-STD-033 Rev. A (Handling, Packing, Shipping
and Use of Moisture/Reflow Sensitive Surface Mount
Devices). Moisture barrier bags (MBB) with desiccant are
provided for the EHHD024A0Axx-SZ modules. These sealed
packages should not be broken until time of use. Once the
original package is broken, the floor life of the product at
conditions of ≤ 30°C and 60% relative humidity varies
according to the MSL rating (see J-STD-033A). The shelf life
for dry packed SMT packages is a minimum of 12 months
from the bag seal date, when stored at the following
conditions: < 40° C, < 90% relative humidity.
Pick and Place
The EHHD024A0A modules use an open frame
construction and are designed for a fully automated
assembly process. The modules are fitted with a label
designed to provide a large surface area for pick and place
operations. The label meets all the requirements for surface
mount processing, as well as safety standards, and is able
to withstand reflow temperatures of up to 300oC. The label
also carries product information such as product code,
serial number and the location of manufacture.
Figure 23. Pick and Place Location.
Nozzle Recommendations
The module weight has been kept to a minimum by using
open frame construction. Even so, these modules have a
relatively large mass when compared to conventional SMT
components. Variables such as nozzle size, tip style,
vacuum pressure and placement speed should be
considered to optimize this process. The minimum
recommended nozzle diameter for reliable operation is
6mm. The maximum nozzle outer diameter, which will safely
fit within the allowable component spacing, is 9 mm.
Oblong or oval nozzles up to 11 x 9 mm may also be used
within the space available.
Tin Lead Soldering
The EHHD024A0A power modules are lead free modules
and can be soldered either in a lead-free solder process or
in a conventional Tin/Lead (Sn/Pb) process. It is
recommended that the customer review data sheets in
order to customize the solder reflow profile for each
application board assembly. The following instructions must
be observed when soldering these units. Failure to observe
these instructions may result in the failure of or cause
damage to the modules, and can adversely affect long-term
reliability.
In a conventional Tin/Lead (Sn/Pb) solder process peak
reflow temperatures are limited to less than 235oC.
Typically, the eutectic solder melts at 183oC, wets the land,
and subsequently wicks the device connection. Sufficient
time must be allowed to fuse the plating on the connection
to ensure a reliablesolder joint. There are several types of
SMT reflow technologies currently used in the industry.
These surface mount power modules can be reliably
soldered using natural forced convection, IR (radiant
infrared), or a combination of convection/IR. For reliable
soldering the solder reflow profile should be established by
accurately measuring the modules CP connector
temperatures.
Lead Free Soldering
The –Z version of the EHHD024A0A modules are lead-free
(Pb-free) and RoHS compliant and are both forward and
backward compatible in a Pb-free and a SnPb soldering
process. Failure to observe the instructions below may
result in the failure of or cause damage to the modules and
can adversely affect long-term reliability.
GE
Datasheet
EHHD024A0A Series: DC-DC Converter Power Module
18 to 75V
dc
Input; 5V
dc
, 24A, 120W Output
March 13, 2014 ©2014 General Electric Corporation. All rights reserved. Page 12
REFLOW TEMP (°C)
REFLOW TIME (S)
Figure 24. Reflow Profile for Tin/Lead (Sn/Pb) process.
MAX TEMP SOLDER (°C)
Figure 25. Time Limit Curve Above 205
o
C for Tin/Lead
(Sn/Pb) process
Pb-free Reflow Profile
Power Systems will comply with J-STD-015 Rev. D
(Moisture/Reflow Sensitivity Classification for Nonhermetic
Solid State Surface Mount Devices) for both Pb-free solder
profiles and MSL classification procedures. This standard
provides a recommended forced-air-convection reflow
profile based on the volume and thickness of the package
(table 4-2). The suggested Pb-free solder paste is Sn/Ag/Cu
(SAC). The recommended linear reflow profile using
Sn/Ag/Cu solder is shown in Figure 26.
Figure 26. Recommended linear reflow profile using
Sn/Ag/Cu solder.
Post Solder Cleaning and Drying Considerations
Post solder cleaning is usually the final circuit-board
assembly process prior to electrical board testing. The result
of inadequate cleaning and drying can affect both the
reliability of a power module and the testability of the
finished circuit-board assembly. For guidance on
appropriate soldering, cleaning and drying procedures, refer
to GE Board
Mounted Power Modules: Soldering and Cleaning Application
Note (AN04-001).
0
50
100
150
200
250
300
Preheat zo ne
max 4
o
Cs
-1
Soak zone
30-240s
Heat zo ne
max 4
o
Cs
-1
Peak Temp 235
o
C
Co o ling
zone
1-4
o
Cs
-1
T
lim
above
205
o
C
200
205
210
215
220
225
230
235
240
0 10 20 30 40 50 60
Per J-STD-020 Rev. D
0
50
100
150
200
250
300
Reflow Time (Seconds)
Reflow Temp (°C)
Heating Zone
1°C/Second
Peak Temp 260°C
* Min. Time Above 235°C
15 Seconds
*Time Above 217°C
60 Seconds
Cooling
Zone
GE
Datasheet
EHHD024A0A Series: DC-DC Converter Power Module
18 to 75V
dc
Input; 5V
dc
, 24A, 120W Output
March 13, 2014 ©2014 General Electric Corporation. All rights reserved. Page 13
EMC Considerations
The circuit and plots in Figure 27 shows a suggested configuration to meet the conducted emission limits of EN55022 Class B.
Figure 27. EMC Considerations
For further information on designing for EMC compliance, please refer to the FLT012A0 data sheet (DS05-028).
VIN = 48V, Io = Io,max, L Line VIN = 48V, Io = Io,max, N Line
EHHD024
FLT012A0
FILTER
GE Datasheet
EHHD024A0A Series: DC-DC Converter Power Module
18 to 75Vdc Input; 5Vdc, 24A, 120W Output
March 13, 2014 ©2014 General Electric Corporation. All rights reserved. Page 14
Mechanical Outline for Through-Hole Module
Dimensions are in millimeters and [inches].
Tolerances: x.x mm ± 0.5 mm [x.xx in. ± 0.02 in.] (Unless otherwise indicated)
x.xx mm ± 0.25 mm [x.xxx in ± 0.010 in.]
*Top side label includes GE name, product designation and date code.
Top
View
Side
View
Bottom
View*
VI-
ON/OFF
VI+
VO-
TRIM
VO+
SENSE-
SENSE+
*For optional pin lengths, see Table 2, Device Coding Scheme and Options
GE Datasheet
EHHD024A0A Series: DC-DC Converter Power Module
18 to 75Vdc Input; 5Vdc, 24A, 120W Output
March 13, 2014 ©2014 General Electric Corporation. All rights reserved. Page 15
Mechanical Outline for Surface Mount Module (-S Option)
Dimensions are in millimeters and [inches].
Tolerances: x.x mm ± 0.5 mm [x.xx in. ± 0.02 in.] (Unless otherwise indicated)
x.xx mm ± 0.25 mm [x.xxx in ± 0.010 in.]
* Top side label includes GE name, product designation and date code.
Top
View
Side
View
B
ottom
View*
VI-
ON/OFF
VI+
VO-
TRIM
VO+
SENSE-
SENSE+
GE Datasheet
EHHD024A0A Series: DC-DC Converter Power Module
18 to 75Vdc Input; 5Vdc, 24A, 120W Output
March 13, 2014 ©2014 General Electric Corporation. All rights reserved. Page 16
Mechanical Outline for Through-Hole Module with Heat Plate (-H Option)
Dimensions are in millimeters and [inches].
Tolerances: x.x mm ± 0.5 mm [x.xx in. ± 0.02 in.] (Unless otherwise indicated)
x.xx mm ± 0.25 mm [x.xxx in ± 0.010 in.]
*For optional pin lengths, see Table 2, Device Coding Scheme and Options
VI-
ON/OFF
VI+
VO-
TRIM
VO+
SENSE-
SENSE+
Top
View
Side
View
Bottom
View*
*Bottom side label includes product designation and date code.
**Side
View
**Side label contains product designation and date code.
GE
Datasheet
EHHD024A0A Series: DC-DC Converter Power Module
18 to 75V
dc
Input; 5V
dc
, 24A, 120W Output
March 13, 2014 ©2014 General Electric Corporation. All rights reserved. Page 17
Mechanical Outline for Through-Hole Module with ¼ Brick Heat Plate (-18H Option)
Dimensions are in millimeters and [inches].
Tolerances: x.x mm ± 0.5 mm [x.xx in. ± 0.02 in.] (Unless otherwise indicated)
x.xx mm ± 0.25 mm [x.xxx in ± 0.010 in.]
Top
View
Side
View
Bottom
View*
**Side
View
**Side label contains product designation and date code.
*For optional pin lengths, see Table 2, Device Coding Scheme and Options
VI-
ON/OFF
VI+
VO-
TRIM
VO+
SENSE-
SENSE+
GE Datasheet
EHHD024A0A Series: DC-DC Converter Power Module
18 to 75Vdc Input; 5Vdc, 24A, 120W Output
March 13, 2014 ©2014 General Electric Corporation. All rights reserved. Page 18
Recommended Pad Layout
Dimensions are in millimeters and [inches].
Tolerances: x.x mm ± 0.5 mm [x.xx in. ± 0.02 in.] (Unless otherwise indicated)
x.xx mm ± 0.25 mm [x.xxx in ± 0.010 in.]
Pin Function
1 Vi(+)
2 ON/OFF
3 Vi(-)
4 Vo(-)
5 SENSE(-)
6 TRIM
7 SENSE(+)
8 Vo(+)
SMT Recommended Pad Layout (Component Side View)
NOTES:
FOR 0.030” X 0.025”
RECTANGULAR PIN, USE
0.050” PLATED THROUGH
HOLE DIAMETER
FOR 0.62 DIA” PIN, USE
0.076” PLATED THROUGH
HOLE DIAMETER
Pin Function
1 Vi(+)
2 ON/OFF
3 Vi(-)
4 Vo(-)
5 SENSE(-)
6 TRIM
7 SENSE(+)
8 Vo(+)
TH Recommended Pad Layout (Component Side View)
5.4[.22]
17.9[.70]
26.1[1.03]
39.0[1.54]
58.4[2.30]
47.2[1.86]
1
2
8
7
6
5
4
3.8[.15]
50.80[2.000]
3.8
[.15]
7.62
[.300]
22.8
[.90]
3.81
[.150]
11.7
[.46]
KEEP
OUT
AREAS
3
1
2
8
7
6
5
4
3.8[.15]
50.80[2.000]
3.8
[.15]
7.62
[.300]
22.8
[.90]
3.81
[.150]
11.7
[.46]
KEEP
OUT
AREAS
5.4[.22]
17.9[.70]
26.1[1.03]
39.0[1.54]
58.4[2.30]
47.2[1.86]
GE Datasheet
EHHD024A0A Series: DC-DC Converter Power Module
18 to 75Vdc Input; 5Vdc, 24A, 120W Output
March 13, 2014 ©2014 General Electric Corporation. All rights reserved. Page 19
Packaging Details
The surface mount versions of the EHHD024A0A (suffix –S)
are supplied as standard in the plastic trays shown in Figure
30.
Tray Specification
Material Antistatic coated PVC
Max surface resistivity 1012Ω/sq
Color Clear
Capacity 12 power modules
Min order quantity 48 pcs (1 box of 4 full trays + 1
empty top tray)
Each tray contains a total of 12 power modules. The trays are
self-stacking and each shipping box for the EHHD024A0A
(suffix –S) surface mount module will contain 4 full trays plus
one empty hold down tray giving a total number of 48 power
modules.
Figure 28. Surface Mount Packaging Tray
GE Datasheet
EHHD024A0A Series: DC-DC Converter Power Module
18 to 75Vdc Input; 5Vdc, 24A, 120W Output
Contact Us
For more information, call us at
USA/Canada:
+1 888 546 3243, or +1 972 244 9288
Asia-Pacific:
+86.021.54279977*808
Europe, Middle-East and Africa:
+49.89.878067-280
India:
+91.80.28411633
www.gecriticalpower.com
March 13, 2014 ©2014 General Electric Corporation. All rights reserved. Version 1.3
Ordering Information
Please contact your GE Sales Representative for pricing, availability and optional features.
Table 1. Device Codes
Product Codes Input Voltage Output
Voltage
Output
Current On/Off Logic Connector
Type Comcodes
EHHD024A0A 41Z 24/48V (18-75Vdc) 5V 24A Negative Through hole 150029828
EHHD024A0A 41-HZ 24/48V (18-75Vdc) 5V 24A Negative Through hole 150029827
EHHD024A0A 41-18HZ 24/48V (18-75Vdc) 5V 24A Negative Through hole 150029830
EHHD024A0A 41-SZ 24/48V (18-75Vdc) 5V 24A Negative Surface mount 150029829
Table 2. Device Coding Scheme and Options
Characteristic Definition
Form Factor E E = 1 /8th Brick
Family Designator HH HH = Hammerhead™ Series
Input Voltage D D = UltraWide Range, 18V-75V
Output Current 024A0 024A0 = 024.0 Amps Maximum Output Current
Output Voltage A A=5V Nominal
Omit = Default Pin Length shown in Mechanical Outline Figures
66 = Pin Length: 3.68 mm ± 0.25mm , (0.145 in. ± 0.010 in.)
88 = Pin Length: 2.79 mm ± 0.25mm , (0.110 in. ± 0.010 in.)
Omit = Positive Logic
11 = Negative Logic
Customer Specific XY XY = Customer Specific Modified Code, Omit for Standard Code
Omit = Standard open Frame Module
H = 1/8th Brick size heat plate, for use with heat sinks (not available
with -S option)
18H = 1/4th Brick size heat plate with unthreaded inserts for use in
coldwall applications (not available with -S option)
S = Surface Mount connections
Omit = RoHS 5/6, Lead Based Solder Used
ZZ = RoHS 6/6 Compliant, Lead free
RatingsOptions
Pin Length
Action following
Protective Shutdown 44 = Auto-restart following shutdown (Overcurrent/Overvoltage)
Must be ordered
On/Off Logic
Mechanical Features
RoHS
Character and Position
H
18H
S
