Operating Temperature Refer to Figure 16 for the measuring point -40 105 °C
Storage Temperature
Input/Output Isolation Voltage 1 minute 1500 Vdc
INPUT CHARACTERISTICS
Operating Input Voltage
Input Under-Voltage Lockout
Turn-On Voltage Threshold
Turn-Off Voltage Threshold
Lockout Hysteresis Voltage
Input Over-Voltage Lockout
Turn-0ff Voltage Threshold
Turn-on Voltage Threshold
Maximum Input Current 100% Load, 18Vin 1.3 A
No-Load Input Current 30 mA
Off Converter Input Current 4
Inrush Current(I2t) 1 A2s
Input Reflected-Ripple Current P-P thru 12µH inductor, 5Hz to 20MHz 5 mA
Input Voltage Ripple Rejection 120 Hz 55 dB
OUTPUT CHARACTERISTICS
Output Voltage Set Point
Output Voltage Regulation
Over Load Io=Io,min to Io,max ±5 ±15 mV
Over Line Vin=18V to 60V ±2 ±7 mV
Over Temperature
Total Output Voltage Range Over sample load, line and temperature 3.16 3.44 V
Output Voltage Ripple and Noise 5Hz to 20MHz bandwidth
Peak-to-Peak Full Load, 1µF ceramic, 10µF tantalum 60 100 mV
RMS Full Load, 1µF ceramic, 10µF tantalum 15 25 mV
Operating Output Current Range 0 4.5 A
Output DC Current-Limit Inception Output Voltage 10% Low 5 6 8 A
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 100% Io,max 65 100 mV
Negative Step Change in Output Current 100% Io,max to 50% Io.max 65 100 mV
Settling Time to 1% of Final value 600 µs
Turn-On Transient
Start-Up Time, From On/Off Control 6 10 ms
Start-Up Time, From Input 5 10
Maximum Output Capacitance Full load; 5% overshoot of Vout at startup 2000 µF
EFFICIENCY
100% Load
ISOLATION CHARACTERISTICS
Isolation Voltage 1500 V
Isolation Resistance 100 MΩ
Isolation Capacitance 500 pF
FEATURE CHARACTERISTICS
Switching Frequency 280 kHz
ON/OFF Control, (Logic Low-Module ON)
Logic Low Von/off at Ion/off=1.0mA 0 0.7 V
Logic High Von/off at Ion/off=0.0 µA 2 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
Output Over-Voltage Protection(Hiccup) Over full temp range; % of nominal Vout 115 125 140 %
GENERAL SPECIFICATIONS
Calculated MTBF Io=80% of Io, max; Tc=40°C 4.5 M hours
Weight (Open Frame) 12.5 grams
NOTES and CONDITIONS S36SS3R304NRFA
Min. Typ. Max. Units
Vin=48V, Io=50%Io.max, Tc=25℃
Tc=-40℃ to 100℃
78 81 %
cross Trim Pin & +Vo or –Vo, Pout≦max rated
70 Vdc
-55 125 °C
18 60 V
16 17 18 V
15 16 17 V
0.5 1.5 2.5 V
64 V
63 V
3.23 3.30 3.37
100 300
m
m/℃
ms
-10 +10 %
V
2
Page 3
ELECTRICAL CHARACTERISTICS CURVES
90
4.0
85
80
75
70
EFFI CI ENC Y (%)
65
60
55
50
0.511.522.533.544.5
OUTPUT CURRENT (A)
18Vin
24Vin
48Vin
60Vin
Figure 1: Efficiency vs. load current for minimum, nominal, and
maximum input voltage at 25
1.00
0.80
°C.
Io=4.5A
I0=2.7A
Io=0.45
3.5
3.0
2.5
2.0
1.5
POWER DISSIPATION (W)
1.0
0.5
0.0
0.511.522.533.544.5
OUTPUT CURRENT(A)
18Vin
24Vin
48Vin
60Vin
Figure 2: Power dissipation vs. load current for minimum,
nominal, and maximum input voltage at 25
°C.
0.60
0.40
INPUT CURRENT (A)
0.20
0.00
15202530354045505560
INPUT V OL TA GE ( V )
Figure 3: Typical input characteristics at room temperature. Figure 4: Turn-on transient at full rated load current (resistive
load) (2 ms/div). Top Trace: Vout (1V/div); Bottom Trace:
ON/OFF Control (2V/div).
3
Page 4
ELECTRICAL CHARACTERISTICS CURVES
)
Figure5: Turn-on transient at zero load current (2 ms/div). Top
Trace: Vout (1V/div); Bottom Trace: ON/OFF Control (2V/div).
Figure 6: Output voltage response to step-change in load
current (50%-100%-50% of Io, max; di/dt = 0.1A/µs). Load
cap: 10µF, 100 m
ceramic capacitor. Top Trace: Vout (50mV/div), Bottom
Trace: Iout (2A/div).
Ω
ESR tantalum capacitor and 1µF
i
s
TEST
12uH
Cs:68uF/100V68uF/100V
ESR< 0.3ESR< 0.3
Ω
20﹫100KHz℃20℃100KHz﹫
Ω
Vi(+)
Vi(-)
Figure 7: Test set-up diagram showing measurement points for
Input Reflected Ripple Current (Figure 8).
Note: Measured input reflected-ripple current with a simulated
source Inductance (L
battery impedance.
of 12 µH. Capacitor Cs offset possible
TEST
Figure 8:
output current and nominal input voltage with 12
impedance and 68
. Input Reflected Ripple Current, i
µF electrolytic capacitor (2 mA/div).
, at full rated
s
µH source
4
Page 5
ELECTRICAL CHARACTERISTICS CURVES
V
E
StripCopper
Vo(+)
SCOPERESISTIV
10u
Vo(-)
Figure 9: Output voltage noise and ripple measurement test
setup. 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.
3.5
1u
LOAD
Figure 10: Output voltage ripple at nominal input voltage and
rated load current (20 mV/div). Load capacitance: 1
capacitor and 10
µF ceramic
µF tantalum capacitor. Bandwidth: 20 MHz.
3.0
2.5
2.0
1.5
OUTPUT VO LT AGE (
1.0
0.5
0.0
Figure 11: Output voltage vs. load current showing typical
current limit curves and converter shutdown points.
Vin=48V
0.02.04.06.08.0
LOA D CURRENT ( A )
5
Page 6
DESIGN CONSIDERATION
A
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 Ω at 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 enduser’s safety agency standard if the system in which the
power module is to be used must meet safety agency
requirements.
When the input source is 60Vdc 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.
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 nonSELV voltage to appear between the output pin and
ground.
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 3A 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.
6
Page 7
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 overvoltage set point, the module will shut down (Hiccup
mode). The modules will try to restart after shutdown. If
the fault condition still exists, the module will shut down
again. This restart trial will continue until the fault
condition is corrected.
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.
Vo(+)
Trim
Vo(-)
Figure 12: 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.
The external resistor value required to obtain a
percentage of output voltage change △Vo% is defined
as:
=−
downRtrim−
Ex. When trim-down –10% (3.3V X 0.9 = 2.97V)
R
trim-down
−
∆
∆
Vo673.32373.20
+
018.0Vo3.3
[]
ΚΩ
2.10
1.0637.32373.20
downRtrim=−
=−
Vo(+)
Trim
Vo(-)
×−
018.01.03.3
+×
R
96.382.10
trim-up
[]
ΚΩ
Figure 13: Circuit configuration for trim-up (increase output
voltage)
If the external resistor is connected between the TRIM
and Vo - the output voltage set point increases. The
external resistor value required to obtain a percentage
output voltage change △Vo% is defined as:
upRtrim−
=−
2636.12
−
∆
018.0Vo3.3
[]
ΚΩ
2.10
Ex. When trim-up +10% (3.3V X 1.1 = 3.63V)
upRtrim=−
=−
Care should be taken to ensure that the maximum
output power of the module remains at or below the
maximum rated power.
2636.12
−×
018.01.03.3
[]
ΚΩ
11.292.10
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. If the remote on/off feature
is not used, please short the on/off pin to Vi(-) for
negative logic and let the pin open for positive logic.
Vi(+)Vo(+)
ON/OFF
Vi(-)
Trim
Vo(-)
Figure 14: Circuit configuration for remote ON/OFF
7
Page 8
THERMAL CONSIDERATIONS
t
r
y
A
Y
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 or a heat sink is
6.35mm (0.25”).
Thermal Derating
Heat can be removed by increasing airflow over the
module. The module’s hot spot temperature is defined a
+105°C. To enhance system reliability, the powe
module should always be operated below the maximum
operating temperature. If the temperature exceeds the
maximum module temperature, reliability of the unit ma
be affected.
FACING PWB
PWB
MODULE
AIR VELOCIT
AND AMBIENT
TEMPERATURE
MEASURED BELOW
THE MODULE
IR FLOW
Note: Wind Tunnel Test Setup Figure Dimensions are in millimeters and (Inches)
Figure 15: Wind tunnel test setup
50.8 (2.0”)
10 (0.4”)
8
Page 9
THERMAL CURVES
Figure 16: Temperature measurement location. Pin locations
are for reference only.
*
The allowed maximum hot spot temperature is defined at
℃
105
5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0.0
40455055606570758085
Figure 17: Output current vs. ambient temperature and air
velocity (Vin=24V)
Output Current(A)
5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0.0
40455055606570758085
Figure 18: Output current vs. ambient temperature and air
velocity (Vin=48V)
S36SS3R304(Standard) Output Current vs. Ambient Temperature and Air Velocity
Output Current(A)
S36SS3R304(Standard) Output Current vs. Ambient Temperature and Air Velocity
Natural
Convection
100LFM
200LFM
300LFM
400LFM
500LFM
600LFM
@ Vin = 24V
Natural
Convection
100LFM
200LFM
300LFM
400LFM
@ Vin = 48V
Ambient Temperature (℃)
Ambient Temperature (℃)
S36SS3R304(Standard) Out put Current vs. Ambient Temperature and Air Vel ocity
Output Current(A)
5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0.0
Natural
Convection
100LFM
200LFM
300LFM
400LFM
500LFM
600LFM
40455055606570758085
@ Vin = 60V
Figure 19: Output current vs. ambient temperature and air
velocity (Vin=60V)
Ambient Temperature (℃)
9
Page 10
MECHANICAL DRAWING
Pin No. Name Function
1 +Vout Positive output voltage
2 -Vout Negative output voltage
3 Trim Output voltage trim
4 NC No Connection
5 NC No Connection
6 NC No Connection
7 NC No Connection
8 ON/OFF ON/OFF Logic
9 NC No Connection
10 NC No Connection
11 -Vin Negative input voltage
12 +Vin Positive input voltage
Telephone:
East Coast: (888) 335 8201
West Coast: (888) 335 8208
Fax: (978) 656 3964
Email:
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.