FEB 16, 2006 revised to JUN 15, 2006 Page 1 of 11 www.power-one.com
HHS40 DC-DC Series Data Sheet
40A Half-Brick Converter
Applications
• Distributed power architectures
• Telecommunications equipment
• LAN/WAN
• Data processing
Features
• RoHS lead solder exemption compliant
• Low profile – 12.7 mm height
• Input/output isolation: 1500 VDC
• Basic insulation
• High efficiency - up to 88% at full load
• Start-up into high capacitive load
• Low conducted and radiated EMI
• Output overcurrent protection
• Output overvoltage protection
• Back-drive protection
• Overtemperature protection
• Remote sense
• Remote on/off (primary referenced), positive
or negative logic
• Output voltage trim adjust
• UL60950-3rd/ CSA C22.2 60950-00,
TUV EN60950-1, IEC60950-1
Description
The HHS40 is a series of high efficiency, high-density, single output dc-dc converters for onboard conversion of
standard telecom and datacom input voltages into isolated low voltage outputs in a through-hole mounting
package. The two-board construction provides a cool environment for control components and the integrated
metal substrate PCB provides superior thermal management for power components resulting in enhanced product
reliability. A heat sink can be conveniently and effectively attached to the IMS base plate for operations in
elevated ambient conditions or where airflow is minimal.
Model Selection
Model Input
Voltage
VDC
Input
Current,
Max 2 ADC
Output
Voltage
Vout,
VDC
Output Rated
Current
I rated,
ADC
Output
Ripple/Noise,
mV p-p
Typical
Efficiency @
I rated, %
HHS40ZE 36 -75 4.5 3.3 40 150 88
HHS40ZD 1 36 -75 3.6 2.5 40 150 88
NOTES:
1 Consult factory for availability
2 @ Vin min.
FEB 16, 2006 revised to JUN 15, 2006 Page 2 of 11 www.power-one.com
HHS40 DC-DC Series Data Sheet
40A Half-Brick Converter
Absolute Maximum Ratings
Stresses in excess of the absolute maximum ratings may cause performance degradation, adversely effect long-
term reliability, and cause permanent damage to the converter.
Table 1. Absolute Maximum Ratings
Parameter Conditions/Description Min Max Units
Continuous 75 VDC Input voltage
Transient (100 ms) 100 VDC
Operating Temperature Baseplate -40 115
°C
Storage Temperature Ambient -55 125 °C
ON/OFF Control Voltage Referenced to -Vin 10 VDC
Environmental, Mechanical & Reliability Specifications
All specifications apply over specified input voltage, output load, and temperature range, unless otherwise noted.
Table 2. Environmental and Mechanical Specifications
Parameter Conditions/Description Min Nom Max Units
Operating Temperature Baseplate Temperature -40 115 °C
Operating Humidity Relative humidity, non-condensing 95 %
Storage Humidity Relative humidity, non-condensing 95 %
Shock Halfsine wave (6ms), 3 axes 50 g
Sinusoidal Vibration GR-63-CORE, Section 5.4.2 1 g
Weight 1.9/54 Oz/g
Water Washing Standard process Yes
MTBF (calculated) Per Bellcore TR-NWT-000332
(Po=60W, Tc=40 °C)
1,500 kHrs
Dimensions (overall) 2.28(57.9) x 2.4(61) x
0.5(12.7)
in (mm)
FEB 16, 2006 revised to JUN 15, 2006 Page 3 of 11 www.power-one.com
HHS40 DC-DC Series Data Sheet
40A Half-Brick Converter
Isolation Specifications
All specifications apply over specified input voltage, output load, and temperature range, unless otherwise noted.
Table 3. Isolation Specifications
Parameter Conditions/Description Min Nom Max Units
Insulation Safety Rating Basic
Input to output, input to base plate 1500 VDC Isolation Voltage
Output to base plate 707 VDC
Isolation Resistance 10 MΩ
Isolation Capacitance Input to Output 1000 pF
Safety Regulatory Compliance
Safety Agency Standard Approved To: Marking
Underwriters Laboratories UL60950/CSA60950-00 cULus
TUV product Service TUV EN60950:2000 TUV PS Baurt mark
CB report IEC60950:1999 N/A.
Input Specifications
All specifications apply over specified input voltage, output load, and temperature range, unless otherwise noted.
Table 4. Input Specifications
Parameter Conditions/Description Min Nom Max Units
Input Voltage Continuous 36 48 75 VDC
Turn-On Input Voltage 1 Ramping Up 32.5 34 35.5 VDC
Turn-Off Input Voltage 1 Ramping Down 31.5 33 34.5 VDC
Input over voltage protection Ramping up 76 84 VDC
Input Reflected Ripple Current 2 Full Load, 12 µH source inductance
50 mA p-p
Inrush Transient Vin = Vin.max 1.0 A2s
1 Refer to Figures 3 & 4 for actual characteristic waveforms.
2 Refer to Figure 10 for test circuit.
FEB 16, 2006 revised to JUN 15, 2006 Page 4 of 11 www.power-one.com
HHS40 DC-DC Series Data Sheet
40A Half-Brick Converter
Output Specifications
All specifications apply over specified input voltage, output load, and temperature range, unless otherwise noted.
Table 5. Output Specifications
Parameter Conditions/Description Min Nom Max Units
Vin = Vin.nom, Full Load
-2.00 2.00 %Vout
Output Voltage Setpoint Accuracy
2.5V
3.3V -1.5 1.5 %Vout
Output Current 1 I
rated 0.5 40 Amps
Line Regulation Vin.min to Vin.max, Irated .25 .5 %Vout
Load Regulation Vin = Vin.nom, 10% to 100%Irated .5 1 %Vout
Output Temperature Regulation (TBaseplate) = -40 °C to +115 °C) 0.03 %/°C
Remote Sense Headroom 3 10 %Vout
Ripple and Noise, DC to 20MHz 1, 5 Over line and load
Tamb= 0 °C to 85 °C
125
35
150
60
mV p-p
mVRMS
75-100-75% load step change,
to 1% error band
di/dt = 0.1A/μs
8
200
13
300
%Vout
μs
Dynamic Regulation
Peak Deviation
Settling Time
Peak Deviation
Settling Time
di/dt = 1A/μs 4 20
100
25
200
%Vout
μs
Turn-On Time
(turn-on via application of Vin)
Time from Vin = UVLO to
regulation band
7 15 ms
Turn-On Time
(turn-on via ON/OFF signal)
Time from ON/OFF signal to
regulation band
5 10 ms
Admissible Load Capacitance Irated, Nom Vin 13,000 μF
Output Current Limit Threshold 2 Vou t≤ 0.97Vout.nom 110 150 %Irated
Short Circuit 2 Hiccup 9 14 ARMS
Turn-On Overshoot 1 5 %Vout
Backdrive Protection No damage to converter Yes
Switching Frequency 300 kHz
Overvoltage Protection,
Clamp, Non Latching
Over all input voltage and load
conditions
120 140 %Vout
Trim Range 3 I
rated, Vin = Vnom 90 110 %Vout
1 At Iout<Iout.min, the output may contain low frequency component that exceeds ripple specifications.
2 Overcurrent protection is non-latching with auto recovery.
3* Vout can be increased up to 10% via the sense leads or up to 10% via the trim function, however total output voltage trim from all
sources should not exceed 10% of Vout
4 Adding output capacitance will have a significant effect in reducing the peak amplitude deviation when powering fast slew-rate loads.
5 Refer to Figure 11 for test circuit.
FEB 16, 2006 revised to JUN 15, 2006 Page 5 of 11 www.power-one.com
HHS40 DC-DC Series Data Sheet
40A Half-Brick Converter
Feature Specifications
All specifications apply over specified input voltage, output load, and temperature range, unless otherwise noted.
Table 6. Feature Specifications
Parameter Conditions/Description Min Nom Max Units
Shutdown (ON/OFF)
Negative Logic (-N suffix)
Converter ON
Source Current
Converter OFF
Open Circuit Voltage
ON/OFF signal is low or the pin is
connected to -Vin – converter is ON
Von/off in reference to -Vin
ON/OFF pin is connected to -Vin
Von/off in reference to -Vin
ON/OFF pin is floating
-0.5
2.5
0.5
1.8
1
10
5
VDC
mADC
VDC
VDC
Shutdown (ON/OFF)
Positive Logic (Std. model)
Converter ON
Open Circuit Voltage
Converter OFF
Source Current
On/Off signal is low or the pin is floating
–converter is OFF
Von/off in reference to -Vin
ON/OFF pin is floating
Von/off in reference to -Vin
ON/OFF pin is connected to -Vin
2.5
-0.5
0.5
10
5
1.8
1
VDC
VDC
VDC
mADC
Overtemperature Protection Baseplate temperature 120 125 130 °C
Characteristic Curv es
HHS40ZE EFFICIENCY VS. LOAD RESPONSE
40
45
50
55
60
65
70
75
80
85
90
95
100
10 20 30 40 50 60 70 80 90 100
LOAD %
EFFICIENCY
%
EFF.(36V) EFF.(48V) EFF.(75V)
Figure 1. HHS40ZE Efficiency vs. Output Load
HHS40ZD EFFICIENCY VS. LOAD RESPONSE
40
45
50
55
60
65
70
75
80
85
90
95
100
10 20 30 40 50 60 70 80 90 100
LOAD %
EFFICIENCY
%
EFF.(36V) EFF.(48V) EFF.(75V)
Figure 2. HHS40ZD Efficiency vs. Output Load
FEB 16, 2006 revised to JUN 15, 2006 Page 6 of 11 www.power-one.com
HHS40 DC-DC Series Data Sheet
40A Half-Brick Converter
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
0 10203040506070
Input Voltage (V)
Input Current (A)
Figure 3. HHS40ZE Input Characteristics
0
0.5
1
1.5
2
2.5
3
3.5
4
0 10203040506070
Input Voltage (V)
Input Current (A)
Figure 4. HHS40ZD Input Characteristics
FEB 16, 2006 revised to JUN 15, 2006 Page 7 of 11 www.power-one.com
HHS40 DC-DC Series Data Sheet
40A Half-Brick Converter
Typical Application
Figure 5 shows the recommended connections for the
HHS40 Series converter.
+Vo
+Sense
Trim
-Sense
-Vo-Vi
+Vi
On/Off
Fuse
C1 C2 C3
HHS60ZX
Figure 5. Typical Application of the HHS40 Seri es
These converter modules do not require any external
components for proper operation. However, if the
distribution of the input voltage to the converter contains
significant inductance, the capacitor C1 may be
required to enhance performance of the converter. A
minimum of a 68 μF electrolytic capacitor with the
ESR<0.7Ω is recommended for the HHS40 Series.
Refer to the “Inrush Current Control Application Note”
on www.power-one.com for suggestions on how to limit
the magnitude of the inrush current.
For output decoupling we recommend to use a 10 μF
tantalum and a 0.1 μF ceramic capacitors connected
directly across the output pins of the converter. Note,
that the capacitors do not substitute the filtering
required by the load.
Shutdown Feature Description
The ON/OFF (# 3) pin of the HHS40 Series converters
are referenced to the –Vin (# 1) pin (see Figure 5).
Both negative and positive logic models are available.
With negative logic (which is denoted by the suffix “–N”
in the part number), when the ON/OFF pin is pulled low,
the unit is turned on.
With the positive logic, when the ON/OFF pin is pulled
low, the output is turned off and the unit goes into a
very low input power mode.
An open collector switch is recommended to control the
voltage between the ON/OFF pin and the -Vin pin of the
converter. The ON/OFF pin is pulled up internally, so
no external voltage source is required.
The user should avoid connecting a resistor
between the ON/OFF pin and the +Vin (# 4) pin.
When the ON/OFF pin is used to achieve remote
control, the user must take care to insure that the
pin reference for the control is actually the -Vin
pin. The control signal must not be referenced
ahead of EMI filtering, or remotely from the unit.
Optically coupling the information and locating the
optical coupler directly at the module will solve
any of these problems.
Note:
If the ON/OFF pin is not used, it can be left floating (positive
logic), or connected to the -Vin pin (negative logic).
Remote Sense
The HHS40 Series converters have the capability
to remotely sense both lines of the output. This
feature moves the effective output voltage
regulation point from the output of the unit to the
point of connection of the remote sense pins.
This feature automatically adjusts the real output
voltage of the converter in order to compensate
for voltage drops in distribution and maintain a
regulated voltage at the point of load. This is
shown in Figures 6 & 7.
If the remote sense feature is not to be used, the
sense pins should be connected locally. The
+Sense (#8) pin should be connected to the
+Vout (#9) pin directly at the output of the
converter and the –Sense (#6) pin should be
connected to the -Vout (#5) pin directly at the
output of the converter.
If sense pins are not connected to load, or the
respective output pins, the converter will not be
damaged, but may not meet the output voltage
regulation specifications.
HHS40Zx
FEB 16, 2006 revised to JUN 15, 2006 Page 8 of 11 www.power-one.com
HHS40 DC-DC Series Data Sheet
40A Half-Brick Converter
OUTPUT VOLTAGE TRIM
Industry Standard (Positive) Trim (-T suffix)
The trim feature allows the user to adjust the output
voltage from its nominal value.
The HHS40 positive-trim (-T) models trim up with a
resistor from the Trim (#7) pin to the +Sense (#8) pin
and trims down with a resistor from the Trim pin to the –
Sense (#6) pin as shown in the Figure 6.
Figure 6. HHS40 Series Positive Trim (-T) Schematic
The equations below determine the trim resistor value
required to achieve a ΔV change in the output voltage.
Ω
⎟
⎠
⎞
⎜
⎝
⎛−
Δ
−
Δ
Δ+
=− k
Vo
upRadj 2
%
100
%225.1 %)100(
Ω
⎟
⎠
⎞
⎜
⎝
⎛−
Δ
=− kdownRadj 2
%
100
where ΔV% is the output voltage change expressed in
percent of the nominal output voltage, Vout.
Negative-Trim Models (No P/N suffix)
All HHS40 negative-trim models trim up with a
resistor connected from the TRIM (#7) pin to the
(-) Sense (#6) pin and trim down with a resistor
from the TRIM pin to the (+) Sense (#8) pin as
shown in Figure 7.
Figure 7. HLS Series Negative Trim Schematic
The following equation determines the required
external resistor value to obtain an output voltage
change of Δ%.
Ω
⎟
⎟
⎠
⎞
⎜
⎜
⎝
⎛−−
Δ
⋅
+
=− kca
baa
downRadj %
100
2
Ω
⎟
⎠
⎞
⎜
⎝
⎛−
Δ
⋅
+
⋅
=− kc
ba ba
upRadj %
100
Trim parameters for a, b & c are defined in the
following table.
Model Name a b c
HHS40ZD /-N 1.04 1.00 3.92
HHS40ZE /-N 1.69 1.00 3.92
FEB 16, 2006 revised to JUN 15, 2006 Page 9 of 11 www.power-one.com
HHS40 DC-DC Series Data Sheet
40A Half-Brick Converter
Notes:
1. When the output voltage is trimmed up, the output power from
the converter must not exceed its maximum rating. The power is
determined by measuring the output voltage on the output pins,
and multiplying it by the output current.
2. In order to avoid creating apparent load regulation degradation, it
is important that the trim resistors are connected directly to the
remote sense pins, and not to the load or to traces going to the
load.
3. The output voltage increase can be accomplished by either the
trim or by the remote sense or by the combination of both. In
any case the absolute maximum output voltage increase shall
not exceed the limits defined in section 6 above.
4. Either Rup or Rdown should be used to adjust the output voltage
according to the equations above. If both Rup and Rdown are
used simultaneously, they will form a resistive divider and the
equations above will not apply
Safety Consideratio ns
The HHS40 Series converters feature 1500 Volt DC
isolation from input to output. The input-to-output
resistance is greater than 10MΩ. These converters are
provided with Basic insulation between input and output
circuits according to all IEC60950 based standards.
Nevertheless, if the system using the converter needs
to receive safety agency approval, certain rules must be
followed in the design of the system. In particular, all of
the creepage and clearance requirements of the end-
use safety requirements must be observed. These
documents include UL60950 - CSA60950-00 and
EN60950, although other or additional requirements
may be needed for specific applications.
The HHS40 Series converters have no internal fuse.
An external fuse must be provided to protect the system
from catastrophic failure, as illustrated in figure 5. Refer
to the “Input Fuse Selection for DC/DC converters”
application note on www.power-one.com for proper
selection of the input fuse. Both input traces and the
chassis ground trace (if applicable) must be capable of
conducting a current of 1.5 times the value of the fuse
without opening. The fuse must not be placed in the
grounded input line, if any.
In order for the output of the HHS40 Series converter to
be considered as SELV (Safety Extra Low Voltage) or
TNV-1, according to all IEC60950 based standards, one
of the following requirements must be met in the system
design:
• If the voltage source feeding the module is SELV or
TNV-2, the output of the converter may be
grounded or ungrounded.
• If the voltage source feeding the module is ELV, the
output of the converter may be considered SELV
only if the output is grounded per the
requirements of the standard.
• If the voltage source feeding the module is a
Hazardous Voltage Secondary Circuit, the
voltage source feeding the module must be
provided with at least Basic insulation
between the source to the converter and any
hazardous voltages. The entire system,
including the HHS40 converter, must pass a
dielectric withstand test for Reinforced
insulation. Design of this type of systems
requires expert engineering and under-
standing of the overall safety requirements
and should be performed by qualified
personnel.
Thermal Considerations
The HHS40 Series converters are designed for
natural or forced convection cooling. The
maximum allowable output current of the
converters is determined by meeting the derating
criteria for all components used in the converters.
For example, the maximum semiconductor
junction temperature is not allowed to exceed
120 °C to ensure reliable long-term operation of
the converters.
The graphs in Figures 8 & 9 show the maximum
output current of the HHS40 Series converters at
different ambient temperatures under both natural
and forced convection. (longitudinal airflow
direction, from pin 1 to pin 4).
For example, from Figure 8, the HHS40ZE
operating at 55 °C can deliver up to 27 A reliably
with 200 LFM forced air, while up to 36 A reliably
with 400 LFM forced air.
FEB 16, 2006 revised to JUN 15, 2006 Page 10 of 11 www.power-one.com
HHS40 DC-DC Series Data Sheet
40A Half-Brick Converter
Power Derating Characte ristics
THERMAL DERATING CURVE
Vin = 54V, Orientation : Vin- to Vin +
0
5
10
15
20
25
30
35
40
45
25 40 55 70 85
Ambient Temperature (Deg C)
Load Current (A)
NC (25 - 35 LFM) 100 LFM 200 LFM 300 LFM 400 LFM
HHS40ZE
Data Rev: 01
Figure 8. HHS40ZE (3.3V) Derating Curve
THERMAL DERATING CURVE
Vin = 54V, Orientation : Vin- to Vin +
0
5
10
15
20
25
30
35
40
45
25 40 55 70 85
A mbien t Temp er at ure (Deg C)
Load Current (A)
NC (25 - 35 LFM) 100 LFM 200 LFM 300 LFM 400 LFM
HHS40ZD
Data Rev: 01
Figure 9. HHS40ZD (2.5V) Derating Curves
Test Setup
Figure 10. Input Reflected Ripple Current Te st Set-up
Note: Measure input reflected-ripple current with a simulated
inductance (Ltest) of 12 µH. Capacitor Cs offsets possible
battery impedance. Measure current as shown above.
DUT
LOAD1
0.1uf
ceramic SCOPE
COPPER STRIPS (2 to 3 inches)
+Vo1
-Vo1
10uF
Tantalum
Figure 11. Output Ripple Measurement Test Setup
Note: Use a 0.1 µf ceramic and 10 µf tantalum capacitor.
Scope measurement should be made using a BNC socket.
BATTER
Y
Cs 220 uF
ESR < 0.1 OHM
@ 20 ºC, 100
kHz
Ltest
12 uH
22 uF
ESR < 0.7 OHM
@ 20 ºC, 100 kHz
Vi(+)
Vi(-)
TO OSCILLOSCOPE
FEB 16, 2006 revised to JUN 15, 2006 Page 11 of 11 www.power-one.com
HHS40 DC-DC Series Data Sheet
40A Half-Brick Converter
Mechanical Drawing
Mechanical Tolerances
Inches Millimeters
X.XX ±0.020 X.X ±0.5
X.XXX ±0.010 X.XX ±0.25
PIN DIA ±0.002 ±0.05
Ordering:
Table 8. Ordering Information
Options P/N Suffixes
Positive (Industry std) - Add “T” suffix Trim
Negative - no suffix required
Positive - no suffix required Remote ON/OFF
Negative - Add “N” suffix
0.18”- Standard - no suffix required
0.11”- Add “8” suffix 1
Pin Length
0.15”- Add “9” suffix 1
Notes: 1 Consult factory for available options.
NUCLEAR AND MEDICAL APPLICATIONS - Power-One products are not designed, intended for use in, or authorized for use as critical
components in life support systems, equipment used in hazardous environments, or nuclear control systems without the express written
consent of the respective divisional president of Power-One, Inc.
TECHNICAL REVISIONS - The appearance of products, including safety agency certifications pictured on labels, may change depending on
the date manufactured. Specifications are subject to change without notice.
Pin Function
1 -Vin
2 Case
3 On/Off
4 +Vin
5 -Vo
6 -Sense
7 Trim
8 +Sense
9 +Vo
Table 7. Pinout/Func tions
