®
®
INNOVATION and EXCELLENCE
A-Series, UWR Models
A-SERIES
Single Output
High-Density, 3.3V
OUT
and 5V
OUT
26-40 Watt DC/DC Converters
The newest products in DATEL’s flagship A-Series are the UWR, 26-40 Watt
isolated singles. Housed in standard 2" x 2" metal packages (which have traditionally
carried 15-20 Watt devices), these power converters supply up to 9 Amps @ 3.3V
or 8 Amps at 5V. They exemplify DATEL’s relentless drive to bring designers more
power/current, in standard packages/pinouts, without compromising reliability or
resorting to thermal specmanship. Input voltage ranges are 10-18V (“D12” models),
18-36V (“D24” models) or 36-75V (“D48”) models.
Employing an advanced, fully synchronous, high-frequency (300-360kHz) for-
ward topology, UWR 26-40W singles attain 88-90% efficiencies enabling full-power
operation to ambient temperatures as high as +55°C without supplemental air flow.
Assembled using fully automated, SMT-on-pcb techniques, these DC/DC’s addition-
ally provide low noise (75mVp-p), high accuracy (±1%), tight line/load regulation
(±0.5%), quick step response (200µsec), and stable no-load operation.
All models feature input pi filters, input undervoltage and overvoltage shutdown,
output overvoltage protection, current limiting, short-circuit protection, and thermal
shutdown. Each model has a V
OUT
trim pin as well as an on/off control function that
may be ordered with either positive or negative polarity. These devices are fully iso-
lated (1500Vdc) and satisfy UL/EN/IEC60950 safety requirements for FUNCTIONAL
insulation. “D48” models (36-75V inputs) are CE marked.
Features
Standard 2" x 2" packages/pinouts
Output voltages/currents:
•
3.3 Volts @ 8/9 Amps
•
5 Volts @ 7/8 Amps
Choice of 3 input voltage ranges:
10-18V, 18-36V, 36-75V
Fully synchronous forward topology
Outstanding performance:
•
±1% setpoint accuracy
•
Efficiencies to 90%
•
Noise as low as 75mVp-p
•
Stable no-load operation
On/off control and V
OUT
trim pins
Fully isolated (1500Vdc); I/O protected
Qual/HALT/EMI tested; Thermal shutdown
UL/EN/IEC60950 certified; CE marked
+INPUT
(1)
+OUTPUT
(6)
SWITCH
CONTROL
–OUTPUT
(7)
–INPUT
(2)
THERMAL
SHUTDOWN
PWM
CONTROLLER
UVLO & OVLO
COMPARATORS
OPTO
ISOLATION
REFERENCE &
ERROR AMP
V
OUT
TRIM
(8)
ON/OFF
CONTROL
(4)
Figure 1. Simplified Schematic
DATEL, Inc., Mansfield, MA 02048 (USA)
•
Tel: (508)339-3000, (800)233-2765 Fax: (508)339-6356
•
Email: sales@datel.com
•
Internet: www.datel.com
A Series
Performance Specifications and Ordering Guide
Output
Model
UWR-3.3/8-D12A
UWR-3.3/9-D24A
UWR-3.3/9-D48A
UWR-5/7-D12A
UWR-5/8-D24A
UWR-5/8-D48A
2 6 - 4 0 W, S I N G L E O U T P U T D C / D C C O N V E RT E R S
➀
Input
Regulation (Max.)
Line
Load
➂
±0.5%
±0.5%
±0.5%
±0.5%
±0.5%
±0.5%
±0.5%
±0.5%
±0.5%
±0.5%
±0.5%
±0.5%
V
OUT
(Volts)
3.3
3.3
3.3
5
5
5
I
OUT
(Amps)
8
9
9
7
8
8
R/N (mVp-p)
➁
Typ.
Max.
75
75
75
75
75
75
110
110
110
110
110
110
V
IN
Nom.
(Volts)
12
24
48
12
24
48
Range
(Volts)
10-18
18-36
36-75
10-18
18-36
36-75
I
IN
➃
(mA/A)
145/2.51
50/1.4
25/0.7
160/3.26
70/1.85
25/0.93
Efficiency
Min.
Typ.
85%
86%
86%
85.5%
86%
86%
87.5%
88.5%
88.5%
89.5%
90%
90%
Package
(Case,
Pinout)
C4, P6
C4, P6
C4, P6
C4, P6
C4, P6
C4, P6
➀
Typical at TA = +25°C under nominal line voltage and full-load conditions, unless noted.
➁
Ripple/Noise (R/N) is tested/speciifed over a 20MHz bandwidth. All models are specified with
an external 0.47µF multi-layer ceramic capacitor installed across their output pins. Using a 10µF
multi-layer ceramic capacitor instead (e.g. TDK part no. C3225X5R1C106M) will further reduce
the R/N to 35mVp-p typical and 75mVp-p maximum.
➂
Load regulation is specified over 0-100% load conditions. All models are stable and regulate
within spec under no-load conditions, with perhaps a slight increase in output ripple/noise.
➃
Nominal line voltage, no-load/full-load conditions.
P A R T
N U M B E R
S T R U C T U R E
M E C H A N I C A L
S P E C I F I C A T I O N S
U WR
-
3.3
/
9
-
D48 A
N
Output Configuration:
U
= Unipolar
Wide Range Input
Nominal Output Voltage:
3.3 or 5 Volts
Maximum Output Current
in Amps
Add "N" suffix
as desired
A-Series
High Reliability
0.45
(11.43)
2.00
(50.80)
METAL CASE
Case C4
INSULATED BASE
0.20 MIN
(5.08)
0.040 ±0.002 DIA.
(1.016 ±0.051)
Input Voltage Range:
D12
= 10-18 Volts (12V nominal)
D24
= 18-36 Volts (24V nominal)
D48
= 36-75 Volts (48V nominal)
0.200
(5.08)
1.800
(45.72)
0.10
(2.54)
5
Part Number Suffixes
UWR 26-40W DC/DC's are designed so the On/Off Control function
on pin 4 can be ordered with either positive (open or "high" = on)
or negative (open = off, pull low = on) polarity. The standard part
number with no suffix denotes positive polarity. Add an "N" suffix
to select negative polarity.
No Suffix
On/Off Control function (positive polarity) on pin 4.
0.100
(2.54)
1
2
0.400
(10.16)
4
6
7
1.200
(30.48)
3 EQ. SP. @
0.400 (10.16)
2.00
(50.80)
8
"N" Suffix
On/Off Control function (negative polarity) on pin 4.
0.40
(10.16)
BOTTOM VIEW
DIMENSIONS ARE IN INCHES (MM)
I/O Connections
Pin
Function P6
1
+Input
2
–Input
3
No Pin
4
On/Off Control
5
No Pin
6
+Output
7
–Output
8
Trim
Note
For D12A and D24A models,
the case is connected to
Pin 2 (–Input).
For D48A models, the case is
connected to Pin 1 (+Input).
2
2 6 - 4 0 W, S I N G L E O U T P U T D C / D C C O N V E RT E R S
UWR Models
Performance/Functional Specifications
Typical @ T
A
= +25°C under nominal line voltage and full-load conditions, unless noted.
➀➁
Input
Input Voltage Range:
D12 Models
D24 Models
D48 Models
Overvoltage Shutdown:
D12 Models
D24 Models
D48 Models
Start-Up Threshold:
➂
D12 Models
D24 Models
D48 Models
Undervoltage Shutdown:
➂
D12 Models
D24 Models
D48 Models
Input Current:
Normal Operating Conditions
Standby Mode (Off, OV, UV)
Input Reflected Ripple Current
Input Filter Type
D12 Models
D24 Models
D48 Models
Reverse-Polarity Protection
On/Off Control:
➃ ➄
"N" Models
10-18 Volts (12V nominal)
18-36 Volts (24V nominal)
36-75 Volts (48V nominal)
19-23 Volts (21V typical)
37-43 Volts (40V typical)
76.5-81 Volts (78V typical)
8.5-10 Volts (9V typical)
16-18 Volts (17V typical)
33.5-36 Volts (35V typical)
7.5-9 Volts (8V typical)
15-17 Volts (16V typical)
31-33.5 Volts (32V typical)
See Ordering Guide
5mA
250mAp-p
Capacitive (13.2µF)
Pi (0.01µF-1µH-6.6µF)
Pi (0.01µF-2.2µH-2µF)
Brief duration, 5A maximum
On = open or 13V - +V
IN
, I
IN
= 1.6mA max.
Off = 0-0.8V, I
IN
= 2.6mA max.
On = 0-0.8V, I
IN
= 1mA max.
Off = open or 3.3-+V
IN
, I
IN
= 1mA max.
Dynamic Characteristics
Dynamic Load Response:
(50-100% load step to 1% V
OUT
)
Start-Up Time:
V
IN to
V
OUT
On/Off
to
V
OUT
Switching Frequency:
UWR-3.3/8-D12A
UWR-3.3/9-D24A, -D48A
UWR-5/7-D12A
UWR-5/8-D24A, -D48A
MTBF
➅
UWR-5/8-D24A
Operating Temperature
(Ambient):
➁
D12A Models
D24A/D48A Models
With Derating
Thermal Shutdown
Storage Temperature
Dimensions
Case Material
200µsec maximum
10ms
10ms
360kHz (±36kHz)
300kHz (±30kHz)
360kHz (±36kHz)
310kHz (±30kHz)
Environmental
Bellcore, ground fixed, full power
25°C ambient
1.6 million hours
+50°C
+55°C
To +100°C (see Derating Curves)
+110°C case
–40 to +120°C
Physical
2" x 2" x 0.45" (50.8 x 50.8 x 11.43mm)
Corrosion resistant steel with
non-conductive, epoxy-based, black
enamel finish and plastic baseplate
Brass, solder coated
2.7 ounces (76.5 grams)
Pin Material
Weight:
Output
V
OUT
Accuracy
(50% load):
Minimum Loading for Stability:
➆
Ripple/Noise
(20MHz BW)
➀ ➅
Line/Load Regulation
Efficiency
Trim Range
➁
Isolation Voltage:
Input-to-Output
Output to Case
Isolation Capacitance
Isolation Resistance
Current Limit Inception
(@98%V
OUT
):
3.3V
OUT
Models
5V
OUT
Models
Short Circuit Current:
(Average)
3.3V
OUT
Models
5V
OUT
Models
Overvoltage Protection:
3.3V
OUT
Models
5V
OUT
Models
Temperature Coefficient
±1.0%, maximum
No load
See Ordering Guide
See Ordering Guide
See Ordering Guide
±5%
1500Vdc minimum
1500Vdc minimum
470pF
100MΩ
10.5-11.5 Amps
8.5-9.5 Amps
3 Amps maximum
4 Amps maximum
Output voltage comparator
3.7-4.1 Volts
5.6-7.1 Volts
±0.02% per °C.
Minimum Loading for Specification:
➁
10% of I
OUT
maximum
Primary to Secondary Insulation Level
Functional
➀
All models are specified with external 0.47µF ceramic output capacitor.
➁
See Technical Notes/Graphs for details.
➂
Applying a voltage to On/Off Control (pin 4) when no input power is applied to the converter
can cause permanent damage.
➃
Output noise may be further reduced with the addition of additional external output
capacitors. See Technical Notes.
➄
The On/Off Control is designed to be driven with open-collector logic or the application
of appropriate voltage levels. Voltages may be referenced to the –Input (pin 2).
➅
Demonstrated MTBF available on request.
3
A Series
2 6 - 4 0 W, S I N G L E O U T P U T D C / D C C O N V E RT E R S
Absolute Maximum Ratings
Input Voltage:
Continuous:
D12A Models
D24A Models
D48A Models
Transient (100msec):
D12A Models
D24A Models
D48A Models
On/Off Control (pin 4) Max. Voltages
Referenced to –Input (pin 2)
No Suffix
"N" Suffix
Input Reverse-Polarity Protection
Output Current
Input Fusing
Certain applications and/or safety agencies may require the installation of
fuses at the inputs of power conversion components. Fuses should also be
used if the possibility of sustained, non-current-limited, input-voltage polarity
reversals exists. For DATEL A-Series UWR 26-40 Watt DC/DC Converters,
you should use slow-blow type fuses with values no greater than the following.
Model
UWR-3.3/8-D12
UWR-3.3/9-D24
UWR-3.3/9-D48
UWR-5/7-D12
UWR-5/8-D24
UWR-5/8-D48
Fuse Value
7 Amps
4 Amps
2 Amps
8 Amps
5 Amps
3 Amps
23 Volts
42 Volts
81 Volts
25 Volts
50 Volts
100 Volts
+V
IN
+V
IN
Current must be <5 Amps. Brief
duration only. Fusing recommended.
Current limited. Devices can
withstand sustained output short
circuits without damage.
+100°C
–40 to +120°C
+300°C
Start-Up and Undervoltage Shutdown
Under normal start-up conditions, UWR 26-40W converters will not begin
to regulate properly until the ramping input voltage exceeds the Start-Up
Threshold. Once operating, devices will turn off when the applied voltage
droops below the Undervoltage Shutdown point. Devices will remain off as
long as the undervoltage condition continues. Units will automatically restart
when the applied voltage is brought back above the Start-Up Threshold.. The
hysteris is built into the function avoids an indeterminate on/off condition at
a single input voltage . See Performance/Functional Specifications table for
actual limits.
On/Off Control
The input-side, remote On/Off Control function (pin 4) can be ordered to
operate with either polarity. Positive-polarity devices (standard, no part-num-
ber suffix) are enabled when pin 4 is left open or is pulled high (+13V to
V
IN
applied with respect to –Input, pin 2, (see Figure 2). Positive-polarity
devices are disabled when pin 4 is pulled low (0-0.8V with respect to –Input).
Negative-polarity devices are off when pin 4 open or pulled high (3.3V to
+V
IN
), and on when pin 4 is pulled low (0-0.8V). See Figure 3.
Case Temperature
Storage Temperature
Lead Temperature
(soldering, 10 sec.)
These are stress ratings. Exposure of devices to any of these conditions may adversely
affect long-term reliability. Proper operation under conditions other than those listed in the
Performance/Functional Specifications Table is not implied.
T E C H N I C A L
N O T E S
Floating Outputs
Since these are isolated DC/DC converters, their outputs are "floating," with
respect to the input. Designers will normally use the –Output (pin 7) as the
ground/return of the load circuit. You can, however, use the +Output (pin 6) as
ground/return to effectively reverse the output polarity.
Minimum Output Loading Requirements
UWR 26-40 Watt converters employ a synchronous-rectifier design topology.
All models regulate within spec and are stable under no-load conditions.
Filtering and Noise Reduction
All UWR 26-40 Watt DC/DC Converters achieve their rated ripple and
noise specifications using the external output capacitor specified in the
Performance/Functional Specifications table. In critical applications, input/
output noise may be further reduced by installing additional external I/O caps.
Input capacitors should be selected for bulk capacitance, low ESR and
high rms-ripple-current ratings. Input capacitors serve as energy-storage
devices to minimize variations in line voltage caused by transient IR drops in
PCB conductors from backplane to the DC/DC. Output capacitors should be
selected for low ESR and appropriate frequency response. All caps should
have appropriate voltage ratings and be mounted as close to the converters
as possible.
The most effective combination of external I/O capacitors will be a function
of your particular load and layout conditions. Our Applications Engineers can
recommend potential solutions. Contact our Applications Engineering Group
for additional details.
1
+INPUT
13V CIRCUIT
4
ON/OFF
CONTROL
5V CIRCUIT
2
–INPUT
Figure 2. Driving the Positive Polarity On/Off Control Pin
4
2 6 - 4 0 W, S I N G L E O U T P U T D C / D C C O N V E RT E R S
UWR Models
Current Limiting
1
+INPUT
4
ON/OFF
CONTROL
2
–INPUT
Figure 3. Driving the Negative Polarity On/Off Control Pin
When output power increases above the rated output current, (see Current
Limit in Performance/Functional Specifications) the DC/DC converter will go
into a current limiting mode. In this condition the output voltage will decrease
proportionately with increases in output current, thereby maintaining a
somewhat constant power dissipation. This is commonly referred to as
power limiting. Current limit inception is defined as the point where the full-
power output voltage falls below the specified tolerance. See Performance/
Functional Specifications. If the load current being drawn from the converter
is significant enough, the unit will go into a short circuit condition. See "Short
Circuit Condition."
Short Circuit Condition
Dynamic control of the remote on/off function is best accomplished with
a mechanical relay or an open-collector/open-drain drive circuit (optically
isolated if appropriate). The drive circuit should be able to sink appropriate
current (see Performance Specs) when activated and withstand appropriate
voltage when deactivated.
Applying an external voltage to pin 4 when no input power is applied to the
converter can cause permanent damage to the converter.
Sync Function
(Optional)
Contact DATEL for further information.
Start-Up Time
The V
IN
to V
OUT
start-up time is the interval of time where the input voltage
crosses the turn-on threshold point, and the fully loaded output voltage enters
and remains within its specified accuracy band. Actual measured times will
vary with input source impedance, external input/output capacitance, and
load. The UWR 26-40 Watt implements a soft start circuit that limits the duty
cycle of the PWM controller at power up, thereby limiting the Input Inrush
current.
The On/Off Control to V
OUT
start-up time assumes the converter has its
nominal input voltage applied but is turned off via the On/Off Control
pin. The specification defines the interval between the time at which
the converter is turned on and the fully loaded output voltage enters
and remains within its specified accuracy band. Similar to the V
IN
to V
OUT
start-up, the On/Off Control to V
OUT
start-up time is also governed by the
internal soft start circuitry and external load capacitance.
Input Overvoltage/Undervoltage Shutdown and Start-Up Threshold
Under normal start-up conditions, devices will not begin to regulate until
the ramping-up input voltage exceeds the Start-Up Threshold Voltage (35V
for "D48" models). Once operating, devices will not turn off until the input
voltage drops below the Undervoltage Shutdown limit (34V for "D48" models).
Subsequent re-start will not occur until the input is brought back up to the
Start-Up Threshold. This built in hysteresis prevents any unstable on/off
situations from occurring at a single input voltage.
Input voltages exceeding the input overvoltage shutdown specification listed
in the Performance/Functional Specifications will cause the device to shut-
down. A built-in hysteresis of 0.6 to 1.6 Volts for all models will not allow the
converter to restart until the input voltage is sufficiently reduced.
When a converter is in current limit mode the output voltages will drop as
the output current demand increases. If the output voltage drops too low, the
magnetically coupled voltage used to develop primary side voltages will also
drop, thereby shutting down the PWM controller.
Following a time-out period the PWM will restart causing the output voltages
to begin ramping to their appropriate values. If the short-circuit condition
persists, another shutdown cycle will be initiated. This on/off cycling is
referred to as "hiccup" mode. The hiccup cycling reduces the average output
current, thereby preventing internal temperatures from rising to excessive
levels. The UWR 26-40 Watt A-Series is capable of enduring an indefinite
short circuit output condition.
Thermal Shutdown
These A-Series converters are equipped with Thermal Shutdown Circuitry.
If environmental conditions cause the internal temperature of the DC/DC
converter to rise above the designed operating temperature, a precision
temperature sensor will power down the unit. When the internal temperature
decreases below the threshold of the temperature sensor the unit will self
start. See Performance/Functional Specifications.
Output Overvoltage Protection
The output voltage is monitored for an overvoltage condition via magnetic
coupling to the primary side. If the output voltage rises to a fault condition,
which could be damaging to the load circuitry (see Performance Specifica-
tions), the sensing circuitry will power down the PWM controller causing the
output voltage to decrease. Following a time-out period the PWM will restart,
causing the output voltage to ramp to its appropriate value. If the fault
condition persists, and the output voltages again climb to excessive levels,
the overvoltage circuitry will initiate another shutdown cycle. This on/off
cycling is referred to as "hiccup" mode.
5
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