Delta Electronics Q48SR User manual

The Delphi Series Q48SR Quarter Brick, 48V input, adjustable single
output, isolated, open frame DC/DC converters are the latest offering
from a world leader in power systems technology and manufacturing —
Delta Electronics, Inc. This product family provides up to 165 watts o
f
power or up to 60A of output current in an industry standard footprint.
This product represents the next generation of design technology which
may be utilized to provide high levels of current at very low outpu
t
voltages required by today’s leading-edge circuitry. Utilizing an
advanced patented thermal and electrical design technology; the Delphi
Series Q48SR converters are capable of providing higher output current
capability with excellent transient response and lower common mode
noise. Featuring a wide operating output voltage range and high curren
t
at low output voltages, these units offer more useable power over a
wide range of ambient operating conditions. The wide range trimmable
output feature allows the user to both reduce and standardize part
numbers across different and/or migrating voltage requirements. This
model covers the output range of 0.8V to 1.9V at 40A.
Delphi Series Q48SR, 165W Quarter Brick Family
DC/DC Power Modules: 48V in, 1.8V/40A out
Datasheet
DS_Q48SR1R840_12212004
Delta Electronics, Inc.
APPLICATIONS
 Telecom/DataCom
 Wireless Networks
 Optical Network Equipment
 Server and Data Storage
 Industrial/Test Equipment
OPTIONS
 Short lead lengths
 Non-latching over voltage protection
 Negative trim
 Positive on/off logic
FEATURES
 High efficiency: 87% @ 1.8V/40A
 Standard footprint:
57.9x36.8x10.2mm (2.28”x1.45”x0.40”)
 Industry standard pin out
 Fixed frequency operation
 Wide output trim range: 0.8V~1.9V
 Fully protected: OTP, OVP, OCP, UVLO
 No minimum load required
 Fast transient response
 Start up into pre-biased load
 Basic insulation
 ISO 9000, TL 9000, ISO 14001 certified
manufacturing facility
 UL/cUL 60950 (US & Canada) Recognized,
and TUV (EN60950) Certified
 CE mark meets 73/23/EEC and 93/68/EEC
directives

TECHNICAL SPECIFICATIONS
(TA=25°C, airflow rate=300 LFM, Vin=48Vdc, nominal Vout unless otherwise noted; mounted on board.)
PARAMETER NOTES and CONDITIONS Q48SR1R840NR A
Min. Typ. Max. Units
ABSOLUTE MAXIMUM RATINGS
Input Voltage
Continuous 80 Vdc
Transient (100ms) 100ms 100 Vdc
Operating Temperature Refer to Figure 24 for the measuring point -40 114 °C
Storage Temperature -55 125 °C
Input/Output Isolation Voltage 1 minute 1500 Vdc
INPUT CHARACTERISTICS
Operating Input Voltage 36 48 75 Vdc
Input Under-Voltage Lockout
Turn-On Voltage Threshold 33 34 35 Vdc
Turn-Off Voltage Threshold 31 32 33 Vdc
Lockout Hysteresis Voltage 1 2 3 Vdc
Maximum Input Current 100% Load, 36Vin 2.7 A
No-Load Input Current 50 100 mA
Off Converter Input Current 10 20 mA
Inrush Current(I2t) 0.03 A2S
Input Reflected-Ripple Current P-P thru 12µH inductor, 5Hz to 20MHz 20 mA
Input Voltage Ripple Rejection 120 Hz 70 dB
OUTPUT CHARACTERISTICS
Output Voltage Set Point Vin=48V, Io=Io.max, Ta=25C 1.75 1.8 1.85 Vdc
Output Voltage Regulation
Over Load Io=Io,min to Io,max ±2 ±5 mV
Over Line Vin=36V to 75V ±2 ±5 mV
Over Temperature Ta=-40C to 85C ±30 ±100 mV
Total Output Voltage Range over sample load, line and temperature 1.69 1.91 V
Output Voltage Ripple and Noise 5Hz to 20MHz bandwidth
Peak-to-Peak Full Load, 1µF ceramic, 10µF tantalum 20 100 mV
RMS Full Load, 1µF ceramic, 10µF tantalum 10 20 mV
Operating Output Current Range 0 40 A
Output DC Current-Limit Inception Output Voltage 10% Low 105 130 %
DYNAMIC CHARACTERISTICS
Output Voltage Current Transient 48V, 10µF Tan & 1µF Ceramic load cap, 0.1A/µs
Positive Step Change in Output Current 50% Io,max to 75% Io,max 50 150 mV
Negative Step Change in Output Current 75% Io,max to 50% Io,max 50 150 mV
Settling Time (within 1% Vout nominal) 100 uS
Turn-On Transient
Start-Up Time, From On/Off Control 15 30 mS
Start-Up Time, From Input 15 30 mS
Maximum Output Capacitance Full load; 5% overshoot of Vout at startup 20000 µF
EFFICIENCY
100% Load 87 %
60% Load 88.5 %
ISOLATION CHARACTERISTICS
Input to Output 1500 Vdc
Isolation Resistance 10 MΩ
Isolation Capacitance 2000 pF
FEATURE CHARACTERISTICS
Switching Frequency 260 kHz
ON/OFF Control, (Logic Low-Module ON)
Logic Low Von/off at Ion/off=1.0mA 0 0.8 V
Logic High Von/off at Ion/off=0.0 µA 15 V
ON/OFF Current Ion/off at Von/off=0.0V 1 mA
Leakage Current Logic High, Von/off=15V 50 uA
Output Voltage Trim Range Across Pins 9 & 5, Pout <= max rated powe
r
0.8 1.9 V
Output Voltage Remote Sense Range Pout <= max rated power 10 %
Output Over-Voltage Protection Over full temp range; % of nominal Vout 115 130 145 %
GENERAL SPECIFICATIONS
MTBF Io=80% of Io, max; Ta=25°C, airflow rate=300 LFM 2.3 M hours
Weight 3232 gramsgrams
Over-Temperature Shutdown Refer to Figure 24 for the measuring point 125 °C
2

3
ELECTRICAL CHARACTERISTICS CURVES
60
65
70
75
80
85
90
95
5 10152025303540
OUTPUT CURRENT (A)
EFFICIENCY (%)
36Vin 48Vin 75Vin
0.0
4.0
8.0
12.0
16.0
20.0
24.0
5 10152025303540
OUTPUT CURRENT(A)
POWER DISSIPATION (W)
36Vin 48Vin 75Vin
Figure 1: Efficiency vs. load current for minimum, nominal, and
maximum input voltage at 25°C. (Vout=1.8V)
Figure 2: Power dissipation vs. load current for minimum,
nominal, and maximum input voltage at 25°C. (Vout=1.8V)
60
65
70
75
80
85
10 20 30 40
OUTPUT CURRENT (A)
EFFICIENCY (%)
36Vin 48Vin 75Vin
0.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0
10 20 30 40
OUTPUT CURRENT(A)
POWER DISSIPATION (W)
36Vin 48Vin 75Vin
Figure 3: Efficiency vs. load current for minimum, nominal, and
maximum input voltage at 25°C. (Vout=0.8 V)
Figure 4: Power dissipation vs. load current for minimum,
nominal, and maximum input voltage at 25°C. (Vout=0.8V)

4
Figure 7: Typical input characteristics at room temperature Figure 8: Turn-on transient at full rated load current (resistive
load) (5 ms/div). Top Trace: Vout; 1V/div; Bottom Trace:
ON/OFF input: 2V/div
0.0
0.5
1.0
1.5
2.0
2.5
3.0
30 35 40 45 50 55 60 65 70 75
INPUT VOLTAGE (V)
INPUT CURREN (A)
Io=40A Io=24A Io=4A
Figure 5: Efficiency vs. output voltage for minimum, nominal,
and maximum input voltage at 25°C. (Iout=40A)
Figure 6: Power dissipation vs. output voltage for minimum,
nominal, and maximum input voltage at 25°C. (Iout=40A)
75
77
79
81
83
85
87
89
91
93
95
0.8 1.0 1.2 1.4 1.6 1.8
OUTPUT VOLTAGE (V)
EFFICIENCY (%)
36Vin 48Vin 75Vin
5.0
6.0
7.0
8.0
9.0
10.0
11.0
12.0
13.0
14.0
15.0
0.8 1.0 1.2 1.4 1.6 1.8
OUTPUT VOLTAGE (V)
POWER DISSIPATION (W)
36Vin 48Vin 75Vin
ELECTRICAL CHARACTERISTICS CURVES

5
ELECTRICAL CHARACTERISTICS CURVES
Figure 9: Turn-on transient at zero load current (5 ms/div).
Top Trace: Vout: 1V/div; Bottom Trace: ON/OFF input:
2V/div
Figure 10: Output voltage response to step-change in load
current (75%-50%-75% of Io, max; di/dt = 0.1A/µs). Load cap:
10µF, tantalum capacitor and 1µF ceramic capacitor. Top Trace:
Vout (50mV/div), Bottom Trace: Iout (20
A
/div). Scope
measurement should be made using a BNC cable (length shorter
than 20 inches). Position the load between 51 mm to 76 mm (2
inches to 3 inches) from the module..
Figure 11: Output voltage response to step-change in load
current (75%-50%-75% of Io, max: di/dt = 2.5A/µs). Load
cap: 470µF, 35m
Ω

ESR solid electrolytic capacitor and 1µF
ceramic capacitor. Top Trace: Vout (100mV/div), Bottom
Trace: Iout (20
A
/div). Scope measurement should be made
using a BNC cable (length shorter than 20 inches
)
. Position
the load between 51 mm to 76 mm (2 inches to 3 inches
)
from the module.
Figure 12: Test set-up diagram showing measurement points for
Input Terminal Ripple Current and Input Reflected Ripple Current.
Note: Measured input reflected-ripple current with a simulated
source Inductance (LTEST) of 12 µH. Capacitor Cs offset possible
battery impedance. Measure current as shown above.

6
ELECTRICAL CHARACTERISTICS CURVES
Figure 13: Input Terminal Ripple Current, ic, at full rated
output current and nominal input voltage with 12µH source
impedance and 33µF electrolytic capacitor (500 mA/div).
Figure 14: Input reflected ripple current, is, through a 12µH
source inductor at nominal input voltage and rated load current
(5 mA/div).
Vo(-)
Vo(+)
10u 1u
Copper Strip
SCOPE RESISTIV
E
LOAD
Figure 15: Output voltage noise and ripple measurement
test setup
Figure 16: Output voltage ripple at nominal input voltage and
rated load current (20 mV/div). Load capacitance: 1µF ceramic
capacitor and 10µF tantalum capacitor. Bandwidth: 20 MHz.
Scope measurement should be made using a BNC cable (length
shorter than 20 inches). Position the load between 51 mm to 76
mm (2 inches to 3 inches) from the module.

7
ELECTRICAL CHARACTERISTICS CURVES
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
0 102030405060
LOAD CURRENT (A)
OUTPUT VOLTAGE (V)
Vin=48V
Figure 17: Output voltage vs. load current showing typical
current limit curves and converter shutdown points.

8
Do not ground one of the input pins without grounding
one of the output pins. This connection may allow a
non-SELV voltage to appear between the output pin
and ground.
The power module has extra-low voltage (ELV) outputs
when all inputs are ELV.
This power module is not internally fused. To achieve
optimum safety and system protection, an input line
fuse is highly recommended. The safety agencies
require a normal-blow fuse with 20A maximum rating to
be installed in the ungrounded lead. A lower rated fuse
can be used based on the maximum inrush transient
energy and maximum input current.
Soldering and Cleaning Considerations
Post solder cleaning is usually the final board assembly
process before the board or system undergoes
electrical testing. Inadequate cleaning and/or drying
may lower the reliability of a power module and
severely affect the finished circuit board assembly test.
Adequate cleaning and/or drying is especially important
for un-encapsulated and/or open frame type power
modules. For assistance on appropriate soldering and
cleaning procedures, please contact Delta’s technical
support team.
DESIGN CONSIDERATIONS
Input Source Impedance
The impedance of the input source connecting to the
DC/DC power modules will interact with the modules
and affect the stability. A low ac-impedance input
source is recommended. If the source inductance is
more than a few µH, we advise adding a 10 to 100 µF
electrolytic capacitor (ESR < 0.7 Ωat 100 kHz)
mounted close to the input of the module to improve the
stability.
Layout and EMC Considerations
Delta’s DC/DC power modules are designed to operate
in a wide variety of systems and applications. For
design assistance with EMC compliance and related
PWB layout issues, please contact Delta’s technical
support team. An external input filter module is
available for easier EMC compliance design.
Application notes to assist designers in addressing
these issues are pending release.
Safety Considerations
The power module must be installed in compliance with
the spacing and separation requirements of the end-
user’s safety agency standard, i.e., UL60950,
CAN/CSA-C22.2 No. 60950-00 and EN60950:2000 and
IEC60950-1999, if the system in which the power
module is to be used must meet safety agency
requirements.
When the input source is 60 Vdc or below, the power
module meets SELV (safety extra-low voltage)
requirements. If the input source is a hazardous voltage
which is greater than 60 Vdc and less than or equal to
75 Vdc, for the module’s output to meet SELV
requirements, all of the following must be met:
 The input source must be insulated from any
hazardous voltages, including the ac mains, with
reinforced insulation.
 One Vi pin and one Vo pin are grounded, or all the
input and output pins are kept floating.
 The input terminals of the module are not operator
accessible.
 A SELV reliability test is conducted on the system
where the module is used to ensure that under a
single fault, hazardous voltage does not appear at
the module’s output.

9
Vo(+)Vi(+)
Vo(-)
Sense(-)
Sense(+)
Vi(-)
ON/OFF
Figure 18: Remote on/off implementation
Remote Sense
Remote sense compensates for voltage drops on the
output by sensing the actual output voltage at the point
of load. The voltage between the remote sense pins
and the output terminals must not exceed the output
voltage sense range given here:
[Vo(+) – Vo(–)] – [SENSE(+) – SENSE(–)] ≤10% ×Vout
This limit includes any increase in voltage due to
remote sense compensation and output voltage set
point adjustment (trim).
Vi(-)
Vi(+)
Vo(-)
Vo(+)
Sense(+)
Sense(-)
Resistance
Contact Contact and Distributio
n
Losses
Figure 19: Effective circuit configuration for remote sense
operation
If the remote sense feature is not used to regulate the
output at the point of load, please connect SENSE(+)
to Vo(+) and SENSE(–) to Vo(–) at the module.
The output voltage can be increased by both the
remote sense and the trim; however, the maximum
increase is the larger of either the remote sense or the
trim, not the sum of both.
When using remote sense and trim, the output voltage
of the module is usually increased, which increases the
power output of the module with the same output
current.
Care should be taken to ensure that the maximum
output power does not exceed the maximum rated
power.
FEATURES DESCRIPTIONS
Over-Current Protection
The modules include an internal output over-current
protection circuit, which will endure current limiting for
an unlimited duration during output overload. If the
output current exceeds the OCP set point, the modules
will automatically shut down (hiccup mode).
The modules will try to restart after shutdown. If the
overload condition still exists, the module will shut down
again. This restart trial will continue until the overload
condition is corrected.
Over-Voltage Protection
The modules include an internal output over-voltage
protection circuit, which monitors the voltage on the
output terminals. If this voltage exceeds the over-
voltage set point, the module will shut down and latch
off. The over-voltage latch is reset by cycling the input
power for one second.
Over-Temperature Protection
The over-temperature protection consists of circuitry
that provides protection from thermal damage. If the
temperature exceeds the over-temperature threshold
the module will shut down.
The module will try to restart after shutdown. If the over-
temperature condition still exists during restart, the
module will shut down again. This restart trial will
continue until the temperature is within specification.
Remote On/Off
The remote on/off feature on the module can be either
negative or positive logic. Negative logic turns the
module on during a logic low and off during a logic high.
Positive logic turns the modules on during a logic high
and off during a logic low.
Remote on/off can be controlled by an external switch
between the on/off terminal and the Vi(-) terminal. The
switch can be an open collector or open drain.
For negative logic if the remote on/off feature is not
used, please short the on/off pin to Vi(-). For positive
logic if the remote on/off feature is not used, please
leave the on/off pin floating.

FEATURES DESCRIPTIONS (CON.)
Output Voltage Adjustment (TRIM)
To increase or decrease the output voltage set point,
connect an external resistor between the TRIM pin
and either the SENSE(+) or SENSE(-). The TRIM pin
should be left open if this feature is not used.
Figure 20: Circuit configuration for trim-up (increase output
voltage)
If the external resistor is connected between the TRIM
and SENSE (+) pins, the output voltage set point
increases (Fig. 20). The external resistor value
required to obtain a percentage of output voltage
change △% is defined as:
Figure 21: Circuit configuration for trim-down (decrease
output voltage)
If the external resistor is connected between the TRIM
and SENSE (-) the output voltage set point decreases
(Fig. 21). The external resistor value required to obtain
a percentage output voltage change △% is defined
as:
()
Ω−
∆
ΚΩ
=∆ k11
10
Rtrim_down
where
Vonom = nominal Vout (3.3V or 1.8V)
∆= trim expressed as decimal fraction, i.e. 40% is
written as 0.4
Ex. When trim down to 0.8V from 1.8V
Vonom = 1.8V
∆= (1.8-0.8)/1.8 = 0.5556
Ω=Ω−=− KK
K
downRtrim 711
5556.0
10
Ωk
The output voltage can be increased by both the remote
sense and the trim, however the maximum increase
allowed is the larger of either the remote sense spec or
the trim spec, not the sum of both.
When using remote sense and trim, the output voltage
of the module is usually increased, which increases the
power output of the module with the same output
current.
Care should be taken to ensure that the maximum
output power of the module remains at or below the
maximum rated power.
Output voltage Resistor value ( )
1.5V 49.00
1.2V 19.00
1.0V 11.50
0.9V 9.0
0.8V 7.0
Figure 22: Trim resistor value example for popular output
voltages. Connect the resistor between the TRIM and
SENSE (-) pins.
10
()
Ω−Ω
⎥
⎦
⎤
⎢
⎣
⎡
∆
−∆+
=kk
ref refonom 1110
V
V1V
)Rtrim_up(∆
()
where
Vonom = nominal Vout (3.3V or 1.8V)
Vref = 1.225V
∆= trim expressed as decimal fraction, i.e. 10% is written
as 0.1
Ex. When trim up to 1.9V from 1.8V
Vonom = 1.8V
Vref = 1.225V
∆= (1.9-1.8)/1.8 = 0.05556
⇒
Ω=Ω−
Ω×
−×
=−
K
K
KupRtrim
18.8811
10
05556.0*225.1
225.105556.18.1

11
THERMAL CURVES
Figure 24: Hot spot location
＊ The allowed maximum hot spot temperature is defined at 114 ℃
THERMAL CONSIDERATIONS
Thermal management is an important part of the
system design. To ensure proper, reliable operation,
sufficient cooling of the power module is needed over
the entire temperature range of the module. Convection
cooling is usually the dominant mode of heat transfer.
Hence, the choice of equipment to characterize the
thermal performance of the power module is a wind
tunnel.
Thermal Testing Setup
Delta’s DC/DC power modules are characterized in
heated vertical wind tunnels that simulate the thermal
environments encountered in most electronics
equipment. This type of equipment commonly uses
vertically mounted circuit cards in cabinet racks in which
the power modules are mounted.
The following figure shows the wind tunnel
characterization setup. The power module is mounted
on a test PWB and is vertically positioned within the
wind tunnel. The space between the neighboring PWB
and the top of the power module is constantly kept at
6.35mm (0.25’’).
Thermal Derating
Heat can be removed by increasing airflow over the
module. The module’s maximum device temperature is
114 ℃and the measured location is illustrated in Figure
24. To enhance system reliability, the power module
should always be operated below the maximum
operating temperature. If the temperature exceeds the
maximum module temperature, reliability of the unit
may be affected.
Note: Wind Tunnel Test Setup Figure Dimensions are in millimeters and (Inche
12.7 (0.5”)
MODULE
A
IR FLOW
50.8
(
2.0”
)
FACING PWB PWB
AIR VELOCIT
Y
AND AMBIENT
TEMPERATURE
MEASURED BELOW
THE MODULE
Figure 23: Wind tunnel test setup

Figure 27: Output current vs. ambient temperature and air
velocity (Vin=48V, Vout=1.0V, transverse orientation)
Figure 26: Output current vs. ambient temperature and air
velocity (Vin=48V, Vout=1.5V, transverse orientation)
Q48SR1R840(Standard) Output Current vs. Ambient Temperature and Air Velocity
@ Vin = 48V, Vo = 1.0V (Tranverse Orientation)
0
5
10
15
20
25
30
35
40
45
20 25 30 35 40 45 50 55 60 65 70 75 80 85
Ambient Temperature (℃)
Output Current(A)
Natural
Convection
100LFM
200LFM
300LFM
400LFM
500LFM
600LFM
Q48SR1R840(Standard) Output Current vs. Ambient Temperature and Air Velocity
@ Vin = 48V, Vo = 1.5V (Tranverse Orientation)
0
5
10
15
20
25
30
35
40
45
20 25 30 35 40 45 50 55 60 65 70 75 80 85
Ambient Temperature (℃)
Output Current(A)
Natural
Convection
100LFM
200LFM
300LFM
400LFM
500LFM
600LFM
Figure 25: Output current vs. ambient temperature and air
velocity (Vin=48V, Vout=1.8V, transverse orientation)
Q48SR1R840(Standard) Output Current vs. Ambient Temperature and Air Velocity
@ Vin = 48V, Vo = 1.8V (Tranverse Orientation)
0
5
10
15
20
25
30
35
40
45
20 25 30 35 40 45 50 55 60 65 70 75 80 85
Ambient Temperature (℃)
Output Current(A)
Natural
Convection
100LFM
200LFM
300LFM
400LFM
500LFM
600LFM
THERMAL CURVES (CON.)
12

13
MECHANICAL DRAWING
Pin No. Name Function
1
2
3
4
5
6
7
8
-Vin
ON/OFF
+Vin
+Vout
+SENSE
TRIM
-SENSE
-Vout
Negative input voltage
Remote ON/OFF
Positive input voltage
Positive output voltage
Positive remote sense
Output voltage trim
Negative remote sense
Negative output voltage
Notes:
1
2
3
Pins 1-3, 5-7 are 1.00mm (0.040”) diameter
Pins 4 and 8 are 1.50mm (0.060”) diameter
All pins are copper with tin plating

14
PART NUMBERING SYSTEM
The part numbering system for Delta’s Q48SR DC/DC converters have the following format:
Q 48 S R 1R8 40 N R
A
Form Factor Input
Voltage Number of Outputs Product Series Output Voltage Output Current ON/OFF Logic Pin Length Space Option Code
Q - Quarter
Brick
48V S - Single R - Single
Board
1R8 - 1.8V 40 - 40A N - Negative
P - Positive
R - 0.170”
N - 0.145”
K - 0.110”
A - Standard
Functions
MODEL LIST
MODEL NAME INPUT OUTPUT EFF @ 100% LOAD
Q48SR1R840NR A 36V~75V 2.7A 0.8V - 1.9V 40A - 72W 87%
Q48SR1R860NR A 36V~75V 4.0A 0.8V - 1.9V 60A - 108W 88%
Q48SR3R335NR A 36V~75V 4.2A 1.7V - 3.6V 35A - 115W 90%
Q48SR3R350NR A 36V~75V 5.9A 1.7V - 3.6V 50A - 165W 91%
Note: Please contact us for factory pre-set fixed output voltages.
CONTACT: www.delta.com.tw/dcdc
USA:
Telephone:
East Coast: [phone]
West Coast: [phone]
Fax: [phone]
Email: [email protected]
Europe:
Telephone: [phone]
Fax: [phone]
Email: [e-mail]
Asia & the rest of world:
Telephone: [phone] x6220
Fax: [phone]
Email: [email protected]
WARRANTY
Delta offers a two (2) year limited warranty. Complete warranty information is listed on our web site or is available
upon request from Delta.
Information furnished by Delta is believed to be accurate and reliable. However, no responsibility is assumed by Delta
for its use, nor for any infringements of patents or other rights of third parties, which may result from its use. No license
is granted by implication or otherwise under any patent or patent rights of Delta. Delta reserves the right to revise
these specifications at any time, without notice.