Delta Electronics Delphi Q48DC User manual

FEATURES
High efficiency: 88%@ ±12.1V/2.7A
Size: 57.9mm x 36.8mm x 9.7mm
(2.28”×1.45”×0.38”)
Industry standard pin out
Fixed frequency operation
Input UVLO, Output OCP, OVP, OTP
2250V isolation
No minimum load required
Adjustable output voltage
ISO 9001, TL 9000, ISO 14001, QS9000,
OHSAS18001 certified manufacturing
facility
UL/cUL 60950-1 (US & Canada), and TUV
(EN60950-1) - pending
Delphi Series Q48DC, 65W Quarter Brick Dual Output
DC/DC Power Modules: 48V in, ±12.1V, 2.7A Output
The Delphi Series Q48DC second generation Quarter Brick, 48V
input, positive and negative bipolar dual output, and isolated DC/DC
converters are the latest offering from a world leader in power system
and technology and manufacturing ―Delta Electronics, Inc. The
Q48DC product family is the second generation in the bipolar dual
output series and it provides even more cost effective solution of
positive and negative bipolar output (output voltage is 12.1V) and up
to 65 watts of power in an industry standard quarter brick package
size. Both output channels can be used independently. With creative
design technology and optimization of component placement, these
converters possess outstanding electrical and thermal performance,
as well as extremely high reliability under highly stressful operating
conditions. All models are fully protected from abnormal input/output
voltage, current, and temperature conditions. The Delphi Series
converters meet all safety requirements with basic insulation.
PRELIMINARY DATASHEET
DS_ Q48DC12003_03112008
OPTIONS
Positive On/Off logic
Output OVP hiccup available
APPLICATIONS
Telecom / DataCom
Wireless Networks
Optical Network Equipment
Server and Data Storage
Industrial / Test Equipment

DS_Q48DC12003_03112008
2
TECHNICAL SPECIFICATIONS
(TA=25°C, airflow rate=300 LFM, Vin=48Vdc, nominal Vout unless otherwise noted.)
PARAMETER NOTES and CONDITIONS Q48DC12003NR A
Min. Typ. Max. Units
ABSOLUTE MAXIMUM RATINGS
Input Voltage
Continuous 80 Vdc
Transient 100ms 100 Vdc
Operating Temperature Refer to Figure 20 for measuring point -40 124 °C
Storage Temperature -55 125 °C
Input/Output Isolation Voltage 2250 Vdc
INPUT CHARACTERISTICS
Operating Input Voltage 36 48 75 Vdc
Input Under-Voltage Lockout
Turn-On Voltage Threshold 32 33.5 35 Vdc
Turn-Off Voltage Threshold 29 30.5 32 Vdc
Lockout Hysteresis Voltage 2 3 4 Vdc
Maximum Input Current 100% Load, 36Vin 2.4 A
No-Load Input Current 50 mA
Off Converter Input Current 10 mA
Inrush Current(I2t) 1 A2s
Input Reflected-Ripple Current P-P thru 12µH inductor, 5Hz to 20MHz 20 mA
Input Voltage Ripple Rejection 120Hz 66 dB
OUTPUT CHARACTERISTICS
Output Voltage Set Point Vin=48V, lo=lo. Max, Tc=25℃Vout 1,2 ±11.98 ±12.10 ±12.22 V
Output Voltage Regulation
Over Load lo1=lo2=lo, min to lo, max Vout 1,2 ±20 ±180 mV
Over Line Vin=36V to 75V,Io1=Io2=full load Vout 1,2 ±20 ±120 mV
Cross Regulation |Io1-Io2|<20% Io,max ±360 mV
Over Temperature Tc=-40℃to 129℃, Io1=Io2= Io, min to Io, max ±120 mV
Total Output Voltage Range Over all load, line and temperature ±11.74 ±12.46 V
Output Voltage Ripple and Noise 5Hz to 20MHz bandwidth
Peak-to-Peak Io1, Io2 Full Load, 1µF ceramic, 10µFtantalum Vout 1, 2 40 80 mV
RMS Io1, Io2 Full Load, 1µF ceramic, 10µF tantalum Vout 1, 2 10 30 mV
Operating Output Current Range Vout 1, 2 0 2.7 A
Output DC Current-Limit Inception Iout 1＋lout 2 7.1 9 A
DYNAMIC CHARACTERISTICS
Output Voltage Current Transient 48V, 10µF Tan & 1µF Ceramic load cap, 0.1A/µs
Vout 1 400 600
Positive Step Change in Output Current Iout1 or Iout2 from50% Io, max
to 75% Io, max Vout 2 400 600 mV
Vout 1 400 600
Negative Step Change in Output Current Iout2 or Iout1 from 75% Io,max
to 50% Io, max Vout 2 400 600 mV
Cross dynamic ±120 ±360 mV
Settling Time (within 1% Vout nominal) 100 us
Turn-On Transient
Delay Time, From On/Off Control 2 ms
Delay Time, From Input 2 ms
Start-up Time, From On/Off Control 20 30 ms
Start-up Time, From Input 20 30 ms
Maximum Output Capacitance Full load; 5% overshoot of Vout at startup 5000 µF
EFFICIENCY
100% Load Iout1, Iout2 full load 88 %
60% Load Iout1, Iout2 60% of full load 86.5 %
ISOLATION CHARACTERISTICS
Input to Output <1 minute 2250 Vdc
Isolation Resistance 10 MΩ
Isolation Capacitance 1500 pF
FEATURE CHARACTERISTICS
Switching Frequency 330 kHz
ON/OFF Control, (Logic Low-Module ON)
Logic Low Von/off at Ion/off=1.0mA -0.7 1.8 V
Logic High Von/off at Ion/off=0.0 µA 3.5 12 V
ON/OFF Current Ion/off at Von/off=0.0V 1 mA
Leakage Current Logic High, Von/off=15V 300 uA
Output Voltage Trim Range Pout ≦max rated power (65W) -17 +5 %
Iout ≦max 120% rated Iout -25 -17 %
Output Over-Voltage Protection Over full temp range; %of nominal Vout 124 130 150 %
GENERAL SPECIFICATIONS
MTBF Io=80% of Io, max; Ta=40°C TBD M hours
Weight 31 grams
Over-Temperature Shutdown Refer to Figure 20 for measuring point 129 °C

DS_Q48DC12003_03112008
3
ELECTRICAL CHARACTERISTICS CURVES
60
63
66
69
72
75
78
81
84
87
90
0.3 0.7 1.1 1.5 1.9 2.3 2.7
OUTPUT CURRENT( A )
EFFICIENCY (%) 1
48Vin 75Vin
36Vin
3.0
3.8
4.6
5.4
6.2
7.0
7.8
8.6
9.4
10.2
0.3 0.7 1.1 1.5 1.9 2.3 2.7
OUTPUT CURRENT(A )
POWER DISSIPATION(W)1
36Vin
48Vin
75Vin
Figure 1: Efficiency vs. load current for minimum, nominal, and
maximum input voltage at 25°C. Io1=Io2. Figure 2: Power dissipation vs. load current for minimum, nominal, and maximum input voltage at 25°C. Io1=Io2.
0.5
0.7
0.9
1.1
1.3
1.5
1.7
1.9
2.1
2.3
2.5
25 30 35 40 45 50 55 60 65 70 75
INPUT V OL TA GE ( V )
INPUT CURRENT (A)1
Figure 3: Typical input characteristics at room temperature
(Io=full load).

DS_Q48DC12003_03112008
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ELECTRICAL CHARACTERISTICS CURVES
Figure 4: Turn-on transient at zero load current (10ms/div).
Vin=48V. Top Trace: Vout: 5V/div; Bottom Trace: ON/OFF input:
5V/div.
Figure 5: Turn-on transient at full rated load current (resistive
load) (10 ms/div). Vin=48V. Top Trace: Vout; 5V/div; Bottom
Trace: ON/OFF input: 5V/div.
Figure 6: Turn-on transient at zero load current (10ms/div).
Vin=48V. Top Trace: Vout: 5V/div; Bottom Trace: Vin input:
50V/div.
Figure 7: Turn-on transient at full rated load current (resistive
load) (10 ms/div). Vin=48V. Top Trace: Vout; 5V/div; Bottom
Trace: Vin input: 50V/div.

DS_Q48DC12003_03112008
5
ELECTRICAL CHARACTERISTICS CURVES
60
63
66
69
72
75
78
81
84
87
90
0.3 0.7 1.1 1.5 1.9 2.3 2.7
OUTPUT CURRENT( A )
EFFICIENCY (%) 1
48Vin 75Vin
36Vin
3.0
3.8
4.6
5.4
6.2
7.0
7.8
8.6
9.4
10.2
0.3 0.7 1.1 1.5 1.9 2.3 2.7
OUTPUT CURRENT( A )
POWER DISSIPATION(W)1
36Vin
48Vin
75Vin
Figure 1: Efficiency vs. load current for minimum, nominal, and
maximum input voltage at 25°C. Io1=Io2. Figure 2: Power dissipation vs. load current for minimum, nominal, and maximum input voltage at 25°C. Io1=Io2.
0.5
0.7
0.9
1.1
1.3
1.5
1.7
1.9
2.1
2.3
2.5
25 30 35 40 45 50 55 60 65 70 75
INPUT V OL TA GE ( V )
INPUT CURRENT (A)1
Figure 3: Typical input characteristics at room temperature
(Io=full load).
ELECTRICAL CHARACTERISTICS CURVES
Figure 8: Output voltage response to step-change in load
current Iout1 (75%-50%-75% of Io, max; di/dt = 0.1A/µs,
200uS/DIV)). Vin=48V. Load cap: 10µF, tantalum capacitor
and 1µF ceramic capacitor. Top trace: Vout (100mV/div),
Bottom trace: Iout (1A/div). Scope measurement should be
made using a BNC cable (length short than 20 inch). Position
the load between 51 mm and 76 mm (2inch and 3 inch) from
the module.
Figure 9: Output voltage response to step-change in load
current Iout2 (75%-50%-75% of Io, max; di/dt = 0.1A/µs,
200uS/DIV). Vin=48V. Load cap: 10µF, tantalum capacitor and
1µF ceramic capacitor. Top trace: Vout (100mV/div), Bottom
trace: Iout (1A/div). Scope measurement should be made using
a BNC cable (length short than 20 inch). Position the load
between 51 mm and 76 mm (2inch and 3 inch) from the module.

DS_Q48DC12003_03112008
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ELECTRICAL CHARACTERISTICS CURVES
Figure 10: 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.
Figure 11: 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 12: Input reflected ripple current, is, through a 12µH
source inductor at nominal input voltage and rated load current
(20 mA/div).

DS_Q48DC12003_03112008
7
ELECTRICAL CHARACTERISTICS CURVES
Vo(-)
Vo(+)
10u 1u
CopperStrip
SCOPE RESISTI
V
LOAD
Figure 13: Output voltage noise and ripple measurement
test setup. Figure 14: Output voltage ripple at nominal input voltage (Vin=48V) and rated load current (Io1=Io2=2.7A,20 mV/div). Load
capacitance: 1µF ceramic capacitor and 10µF tantalum capacitor.
Bandwidth: 20 MHz. (See Figure 13). Scope measurement should
be made using a BNC cable (length short than 20 inch). Position
the load between 51 mm and 76 mm (2inch and 3 inch) from the
module.
0
1
2
3
4
5
6
7
8
9
10
11
12
13
0123456789
LOA D CURRENT( A )
OUTPUT VOLTAGE(V) 1
Figure 15: Output voltage vs. load current showing typical
current limit curves and converter shutdown points.

DS_Q48DC12003_03112008
8
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 insulate from any
hazardous voltage, including the ac mains, with
reinforced insulation.
One Vi pin and one Vo pin are grounder, or all the
input and output pins are kept floating.
The input terminals of the module are not operator
accessible.
If the metal baseplate is grounded the output must
be also grounded.
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.
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 7A 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.

DS_Q48DC12003_03112008
9
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 either cycling the input
power or by toggling the on/off signal 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 to floating.
Vo(+)
Trim
Vo(-)
Rtn
Vi(+)
Vi(-)
ON/OFF
Figure 16: Remote on/off implementation

DS_Q48DC12003_03112008
10
FEATURES DESCRIPTIONS (CON.)
Output Voltage Adjustment (TRIM)
To increase or decrease the output voltage set point,
the modules may be connected with an external
resistor between the TRIM pin and either the Vo(+) or
Vo(-). The TRIM pin should be left open if this feature
is not used.
Rtrim-down
Vo(+)
Trim
Vo(-)
Rtn
Figure 17: Circuit configuration for trim-down (decrease
output voltage)
If the external resistor is connected between the TRIM
and Vo(+) pins, the output voltage set point decreases
(Fig.17). The external resistor value required to obtain
a percentage of output voltage change △% is defined
as:
() Ω
⎥
⎦
⎤
⎢
⎣
⎡−
Δ
=− KdownRtrim 46.9
749
Ex. When Trim-down -25%(12.1V×0.75=9.08V)
() ()
Ω=Ω
⎥
⎦
⎤
⎢
⎣
⎡−=− KKdownRtrim 5.2046.9
25
749
Vo(+)
Trim
Vo(-)
Rtn
Rtrim-up
Figure 18: Circuit configuration for trim-up (increase output
voltage)
If the external resistor is connected between the TRIM and
Rtn the output voltage set point increases (Fig.18). The
external resistor value required to obtain a percentage
output voltage change △% is defined as:
()
Ω
Δ
=− KupRtrim 197
Ex. When Trim-up +5%(12 .1V×1.05=12.71V)
() Ω==− KupRtrim 4.39
5
197
When using 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.