PRELIMINARY
®
®
A SUBSIDIARY OF C&D TECHNOLOGIES
Triple Output
TWR Models
Isolated, High Reliability
1" x 2" DC/DC Converters
Features
■
■
■
±12V/±15V and 3.3V/5V outputs
10-18V, 18-36V or 36-75V inputs
Up to 22.5 Watts total output power with
overtemperature shutdown
To 87% efficiency; 80-100mV Ripple
and Noise
1" x 2" x 0.5" encapsulated package
1500Vdc isolation for both outputs
UL 60950, CSA-C22.2 No. 234, EN60950
safety approvals
Extensive self-protection with short
circuit shutdown
Output overvoltage and overcurrent
protection
Input under and overvoltage shutdown
Ideal for mixed analog/digital systems
■
■
■
■
■
■
■
■
Packaged in 1" x 2" encapsulated modules, the TWR 22W series DC/DC converters
offer three outputs arranged as a unipolar low voltage supply and a higher voltage
bipolar output pair. The unipolar section supplies either +3.3V at 4A maximum or
+5V at 3A maximum. The bipolar outputs are either ±12Vdc at 300mA maximum or
±15Vdc at 250mA and are ideal for op amps, linear or analog circuits. A single TWR
converter can power applications with combined analog and digital circuits such as a
CPU-controlled voice switch, embedded telephone modem or analytical instruments.
The input section is fully isolated from the outputs up to 1500Vdc minimum using
Basic insulation. Three wide input ranges are available including 10-18V (12Vdc
nominal), 18-36V (24Vdc nomimal) or 36-75V (48Vdc nominal). Peak-to-peak
output ripple/noise is typically 80-100mV at full load. Efficiencies range up to 87%.
The TWR 22W series outputs will limit their current if driven to overload and may
be short circuited indefinitely without damage. The inputs will shut down if input voltage
is either over or under limits or has reversed input voltage. These converters will
operate up to +65°C with no derating or at higher temperatures with adequate airflow.
The unipolar output features line and load regulation of ±1%. Excellent dynamic
response assures transient load change settling within 100 microseconds. Other
convenience features include a remote On/Off control to turn the outputs on via
digital logic, CPU bit, control transistor or a relay.
Fabrication uses DATEL’s advanced surface mount automated pick-and-place
assembly and computer-controlled parameter testing. All TWR 22W series are
designed to meet safety requirements in UL, EN60950 and CSA-C22.2 No.234.
½½½½½½
½½½½½½½½
½½½½½½
½½½½½½½½
½½½½½½
½½½½½
½½½½½½
½½½½½½½½
½½½½½½
½½½½½½
½½½½½½½
½½½½½½½
½½½½½½½½
½½½
½½½½½½½½½½
½½½½
½½½½½
½½½½½½
½½½½½½
½½½½½½½½½½½½
½½½½½½½½
½½½½½½½½½½½½
½½½½½½½½½½½½½½½
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
XWR Series
Performance Specifications and Ordering Guide
➀
Output
R/N (mvp-p)
Model
TWR-3.3/4-12/300-D12
TWR-3.3/4-12/300-D24
TWR-3.3/4-12/300-D48
TWR-3.3/4-15/250-D12
TWR-3.3/4-15/250-D24
TWR-3.3/4-15/250-D48
TWR-5/3-12/300-D12
TWR-5/3-12/300-D24
TWR-5/3-12/300-D48
TWR-5/3-15/250-D12
TWR-5/3-15/250-D24
TWR-5/3-15/250-D48
V
OUT
Volts
3.3
±12
3.3
±12
3.3
±12
3.3
±15
3.3
±15
3.3
±15
5
±12
5
±12
5
±12
5
±15
5
±15
5
±15
I
OUT
Amps
4
0.3
4
0.3
4
0.3
4
0.25
4
0.25
4
0.25
3
0.3
3
0.3
3
0.3
3
0.25
3
0.25
3
0.25
Typ.
80
100
80
100
80
100
80
100
80
100
80
100
80
100
80
100
80
100
80
100
80
100
80
100
Max.
100
150
100
150
100
150
100
150
100
150
100
150
100
150
100
150
100
150
100
150
100
150
100
150
2 2 WAT T, T R I P L E O U T P U T D C / D C C O N V E R T E R S
Input
Regulation (Max.)
Line
±1%
±5%
±1%
±5%
±1%
±5%
±1%
±5%
±1%
±5%
±1%
±5%
±1%
±5%
±1%
±5%
±1%
±5%
±1%
±5%
±1%
±5%
±1%
±5%
Load
±1%
±5%
±1%
±5%
±1%
±5%
±1%
±5%
±1%
±5%
±1%
±5%
±1%
±5%
±1%
±5%
±1%
±5%
±1%
±5%
±1%
±5%
±1%
±5%
V
IN
Nom.
(Volts)
12
24
48
12
24
48
12
24
48
12
24
48
Range
(Volts)
10-18
18-36
36-75
10-18
18-36
36-75
10-18
18-36
36-75
10-18
18-36
36-75
Input Current
No Load
(mA)
170
25
25
170
25
25
25
90
25
170
80
45
Full Load
(Amps)
2
1
0.5
2.1
1
0.5
2.2
1.1
0.6
2.3
1.1
0.6
Efficiency
Min.
82%
85%
85%
82%
85%
85%
83%
83%
85%
81%
83%
84%
Typ.
85%
87%
87%
84%
87%
87%
85%
86%
87%
83%
86%
87%
Packag
(Case/
Pinout)
C39/P61
C39/P61
C39/P61
C39/P61
C39/P61
C39/P61
C39/P61
C39/P61
C39/P61
C39/P61
C39/P61
C39/P61
T WR
-
5
/
3
-
12
/
300
-
D48 N
Output Configuration
Wide Range Input
Nominal Primary Output
Maximum Primary Output
On/Off Control Polarity
Input Voltage Range
Maximum Auxiliary Output
Nominal Auxiliary Output
See page 9 for complete Part Number Structure and Ordering Information
M E C H A N I C A L
S P E C I F I C A T I O N S
½½½½
½½½½½½½
½½½½½½½½½½½½
½½½½
½½½½½½½
I/O Connections
½½½½½½½½
½½½½½½½½½½½½
½½½½½½½½
½½½½½½
½½½½½½½½½½½½½½½½½
½½½½½½½½½½½½½½
½½½½½
½½½½½½½
½
½
½
½
½
½
½½½½½½½½½½½
½½½½½½½½½½½½½½½½½½½½½½½½½½½½½
½½½½
½½½½½½
½½½½½
½½½½½½
Pin
1
2
3
4
5
6
7
Function P61
+Input
–Input
On/Off Control
+12V/15V Output
–12V/15V Output
Common
+3.3/5V Output
½½½½½
½½½½½½
½½½½
½½½½½
½½½½½
½½½½½½½ ½½½½½½½
½½½½½½½
½
Alternate pin length and/or other output
voltages are available under special
quantity order.
½½½½
½½½½½½
2
2 2 WAT T, T R I P L E O U T P U T D C / D C C O N V E R T E R S
TWR Models
Short Circuit Duration
(no damage)
Overvoltage Protection:
3.3V or 5V Output
±12V or ±15V Outputs
Performance/Functional Specifications
Input
See Ordering Guide
Continuous, output shorted to ground
3.8Vdc minimum, 4.2Vdc maximum
30Vdc maximum
Method: magnetic feedback
Typical @ T
A
= +25°C under nominal line voltage, nominal output voltage, natural air convection,
external caps and full-load conditions unless noted.
➀
Input Voltage Range
Start-Up Threshold:
➂
12V Models
24V Models
48V Models
Undervoltage Shutdown:
➂
12V Models
24V Models
48V Models
Overvoltage Shutdown:
12V Models
24V Models
48V Models
Reflected (Back) Ripple Current
➁
Dynamic Characteristics
Dynamic Load Response
(50-100% loadstep)
3.3V or 5V Output
150µsec to ±1.5% of final value
±12V or ±15V Outputs
150µsec to ±10% of final value
Start-Up Time
TBD msec for V
OUT
= nominal
V
IN
to V
OUT
regulated
Switching Frequency
330kHz ±20kHz
9V minimum, 9.5V typical
16.5V minimum, 17V typical
34V minimum, 35V typical
8V minimum, 8.5V typical
16V minimum, 16.5V typical
32.5V minimum, 34.5V typical
20V typical, 21V maximum
38V typical, 40V maximum
78.5V typical, 81V maximum
12mA typical, 20mAp-p maximum
See Ordering Guide
25mA typical, 50mA maximum
170mA typical, 200mA maximum
TBD
Off = ground pin to +1.2V maximum
On = open pin to +V
IN
maximum
2mA maximum
On = ground pin to +1.2V maximum
Off = open pin to +V
IN
maximum
18mA maximum
Input Current:
Full Load Conditions
No Load V
IN
= nominal
12V and 24V Models
48V Models
Low-Line Voltage (V
IN
= V
MIN
, full load)
Remote On/Off Control
➄
Positive Logic (no model suffix)
Current
Negative Logic (N model suffix)
Current
V
OUT
Range
V
OUT
Accuracy:
3.3V or 5V Output
±12V or ±15V Outputs
Environmental
Calculated MTBF
➃
TBD
Operating Temperature:
(Ambient)
➆
–40 to +65°C
No Derating (Natural convection)
With Derating
See Derating Curves
–40 to +100°C maximum
Operating Case Temperature
–40 to +120°C
Storage Temperature
Thermal Protection/Shutdown
Density Altitude
Relative Humidity
Dimensions
Case and Header Material
Pin Dimensions/Material
Weight
Electromagnetic Interference
Safety
+110°C minimum to 120°C maximum
0 to 10,000 feet
10% to 90%, non-condensing
Physical
See Mechanical Specifications
Black Diallyl Phthalate plastic
0.04" (1.016mm) dia. solder-coated brass
TBD
TBD
UL/cUL 60950 CSA-C22.2 No.234
IEC/EN 60950
Output
See Ordering Guide
±1% of V
NOM
±10% of V
NOM
(See Technical Notes)
±0.02% of V
OUT
range/°C
See Technical Notes
No minimum load
60mA minimum load
See Ordering Guide
See Ordering Guide & Technical Notes
See Ordering Guide
TBD
TBD
1500Vdc minimum
100MΩ
470pF
Functional insulation
5 Amps minimum, 6.2 Amps maximum
4 Amps minimum, 5.2 Amps maximum
0.36 Amps minimum, 1 Amp maximum
0.5 Amps minimum, 1.2 Amps maximum
Magnetic feedback
Magnetic feedback plus voltage clamp
Current limiting with hiccup autorestore.
Remove overload for recovery.
2 Amps maximum
1 Amp maximum
Temperature Coefficient
Minimum Loading:
3.3V or 5V Output
±12V or ±15V Outputs
Ripple/Noise
(20MHz BW)
➀ ➁ ➃
Line/Load Regulation
➉
Efficiency
Maximum Capacitive Loading:
3.3V or 5V Output
±12V or ±15V Outputs
Isolation:
Input to Output Voltage
Resistance
Capacitance
Isolation Safety Rating
Current Limit Inception:
(98% of V
OUT
)
3.3V Output
5V Output
±12V Outputs
±15V Outputs
Short-Circuit Detection:
3.3V or 5V Output
±12V or ±15V Outputs
Short-Circuit Potection Method
Short-Circuit Current:
3.3V or 5V Output
±12V or ±15V Outputs
➀
All models are tested/specified with two external 0.047µF output capacitors. These capacitors
are necessary to accommodate our test equipment and may not be required to achieve speci-
fied performance in your applications. All models are stable and regulate within spec under
no-load conditions.
➁
Input Reflected Ripple Current is tested/specified over a 20MHz bandwidth. Input filtering is
C
IN
= 33µF, 100V tantalum; C
BUS
= 220µF, 100V electrolytic; L
BUS
= 12µH. See Technical Notes.
➂
For consistent operation, the instantaneous input voltage for full output load must not go below
the low shutdown voltage
AT ALL TIMES.
Beware of excessive voltage drop from long input
wiring. For reliable startup, be sure to apply input power promptly and fully as a step function.
➃
Mean Time Before Failure is calculated using the Telcordia (Belcore) SR-332 Method 1, Case
3, ground fixed conditions, T
CASE
= +25°C, full load, natural air convection.
➄
The On/Off Control may be driven with external logic or the application of appropriate voltages
(referenced to Common). The On/Off Control input should use either an open collector/open drain
transistor or logic gate which does not exceed +V
IN
. The On/Off Control may be supplied with with
negative logic (LO = on, HI = off) using the "N" model suffix.
➅
Maximum Power Derating curves indicate an average current at nominal input voltage. At higher
temperatures and/or lower airflow, the DC/DC converter will tolerate brief full current outputs if
the total RMS current over time does not exceed the derating curve.
➆
All models are fully operational and meet published specifications, including cold start at –40°C.
➇
Output noise may be further reduced by adding an external filter. See I/O Filtering and Noise
Reduction.
➈
The outputs share a common isolated return. The two output sections are not isolated from
each other.
➉
Regulation specifications describe the deviation as the line input voltage or output load current
is varied from a nominal midpoint value to either extreme.
3
XWR Series
2 2 WAT T, T R I P L E O U T P U T D C / D C C O N V E R T E R S
Absolute Maximum Ratings
Input Voltage:
Continuous or transient
12V Models
24V Models
48V Models
On/Off Control
(Pin 1)
Input Reverse-Polarity Protection
Output Overvoltage Protection
Output Current
Input 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. Once
operating, devices will not turn off until the instantaneous input voltage drops
below the Undervoltage Shutdown limit. Subsequent restart will not occur
until the input is brought back up to the Start-Up Threshold. This built-in
hysteresis avoids any unstable on/off situations occurring at a single input
voltage. However, you should be aware that poorly regulated input sources
and/or higher input impedance sources (including long power leads) which
have outputs near these voltages may cause cycling of the converter outputs.
Ripple Current and Output Noise
All TWR converters are tested and specified for input reflected ripple current
(also called Back Ripple Current) and output noise using specified filter com-
ponents and test circuit layout as shown in the figures below. Input capacitors
must be selected for low ESR, high AC current-carrying capability at the
converter’s switching frequency and adequate bulk capacitance. The switch-
ing nature of DC/DC converters requires this low AC impedance to absorb
the current pulses reflected back from the converter’s input.
½½½
½½½½½½½½½½½½
½½½½½½½
½½½½½
½
½½½
½
½½½
½
½½½½½½
½
½½½
½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½
½
½½½
½½½½½½½
½
½½
½½½½½½½
½
½½
–0.3V minimum or +18V maximum
–0.3V minimum or +36V maximum
–0.3V minimum or +75V maximum
–0.3V minimum or +V
IN
maximum
See Fuse section
V
OUT
+20% maximum
Current limited. Devices can
withstand sustained output short
circuits without damage.
–40 to +120°C
+300°C
Storage Temperature
Lead Temperature
(soldering 10 sec. max.)
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
Load Dependency and Regulation
The high voltage bipolar output section derives its regulation as a slave to the
low voltage unipolar output. Be aware that large load changes on the unipolar
section will change the voltage somewhat on the bipolar section. To retain
proper regulation, the bipolar voltage section must have a minimum load of
at least 10% of rated full output. With this minimal load (or greater), the high
voltage bipolar section will meet all its regulation specifications. If there is no
load, the output voltage may exceed the regulation somewhat.
Input Fusing
Certain applications and/or safety agencies require fuses at the inputs of
power conversion components. Fuses should also be used if there is the pos-
sibility of sustained, non-current limited reverse input polarity. DATEL recom-
mends slow-blow type fuses approximately twice the maximum input current
at nominal input voltage but no greater than 5 Amps. Install these fuses in the
high side (ungrounded input) power lead to the converter.
Input Voltage
12 Volts
24 Volts
48 Volts
Input Source Impedance
The external source supplying input power must have low AC impedance.
Failure to insure adequate low AC impedance may cause stability problems,
increased output noise, oscillation, poor settling and aborted start-up. The
converter’s built-in front end filtering will be sufficient in most applications.
However, if additional AC impedance reduction is needed, consider adding
an external capacitor across the input terminals mounted close to the con-
verter. The capacitor should have low internal Equivalent Series Resistance
(ESR) and low inductance. Often, two or more capacitors are used in parallel.
A ceramic capacitor gives very low AC impedance while a parallel electrolytic
capacitor offers improved energy storage.
Fuse Value
4 Amps
2 Amps
1 Amp
½
½
½½
½½½½½½
Figure 2. Measuring Input Ripple Current
Output Overcurrent Detection
Overloading the power converter’s output for extended periods (but not a
short circuit) at high ambient temperatures may overheat the output com-
ponents and possibly lead to component failure. Brief moderate overcurrent
operation (such as charging up reasonably-sized external bypass capacitors
when first starting) will not cause problems. The TWR series include current
limiting to avoid heat damage. However, you should remove a sustained
overcurrent condition promptly as soon as it is detected. Combinations of
low airflow and/or high ambient temperature for extended periods may cause
overheating even though current limiting is in place.
Current Return Paths
Make sure to use adequately sized conductors between the output load and
the Common connection. Avoid simply connecting high current returns only
through the ground plane unless there is adequate copper thickness. Also,
route the input and output circuits directly to the Common pins. Failure to
observe proper wiring may cause instability, poor regulation, increased noise,
aborted start-up or other undefined operation.
4
2 2 WAT T, T R I P L E O U T P U T D C / D C C O N V E R T E R S
TWR Models
Safety Considerations
The TWR’s must be installed with consideration for any local safety,
certification or regulatory requirements. These vary widely but generally are
concerned with properly sized conductors, adequate clearance between
higher voltage circuits, life testing, thermal stress analysis of components
and flammability of components. Contact DATEL if you need further advice
on these topics.
Remote On/Off Control
The TWR models include an input pin which can turn on or shut off the
converter by remote signal. For positive logic models (no model number
suffix), if this pin is left open, the converter will always be enabled as long as
proper input power is present. On/Off signal currents are referred to the Input
Common pin on the converter. There is a short time delay of several mil-
liseconds (see the specifications) for turn on, assuming there is no significant
external output capacitance.
The On/Off Control may also be supplied with negative logic (LO = on, HI =
off) using the “N” model number suffix. Here again, leaving the pin open on
either model will enable the converter. Positive logic models must have this
control pin pulled down for shutoff. Negative logic models must pull up this
control pin for shutoff.
Dynamic control of this On/Off input is best done with either a mechanical
relay (ground the pin to turn it off), solid state relay (SSR), an open collector
or open drain transistor, CPU bit or a logic gate. The pull down current is
18mA max. Observe the voltage limits listed in the specifications for proper
operation. Suggested circuits are shown below.
½½½½½½
½½½½
½½½½½
½½½½½½
½½½½½½½
½½½½½½
½½½½½½
½½½½½½
Isolation Considerations
These converters use both transformer and optical coupling to isolate the
inputs from the outputs. Ideal “floating” isolation implies ZERO CURRENT
flowing between the two Common return sections of the input and output up
to the working isolation voltage limit. Real-world isolation on this converter
includes both an AC current path (through some small coupling capaci-
tance) and some DC leakage current between the two ground systems. To
avoid difficulties in your application, be sure that there are not wideband,
high amplitude AC difference voltages between the two ground systems. In
addition, ground difference voltages applied by your external circuits which
exceed the isolation voltage, even momentarily, may damage the converter’s
isolation barrier. This can either destroy the converter or instantly render it
non-isolated.
Current Limiting and Short Circuit Condition
As the output load increases above its maximum rated value, the converter
will enter current limiting mode. The output voltage will decrease and the
converter will essentially deliver constant power. This is commonly called
power limiting.
If the current continues to increase, the converter will enter short circuit
operation and the PWM controller will shut down. Following a time-out
period, the converter will automatically attempt to restart. If the short circuit
is detected again, the converter will shut down and the cycle will repeat. This
operation is called hiccup autorecovery. Please be aware that excessive
external output capacitance may interfere with the hiccup autorestart.
Output Filtering and Noise Reduction
All switching DC/DC converters produce wideband output noise which
radiates both through the wiring (conducted emission) and is broadcast into
the air (radiated emission). This output noise may be attenuated by adding
a small amount of capacitance in parallel with the output terminals. Please
refer to the maximum output capacitance in the Specifications.
½½½½½½½½½½
½½½½½½½
½½½½½½½½
Figure 3. On/Off Control With An External CMOS Gate
The amount of capacitance to add depends on the placement of the cap
(near the converter versus near the load), the distance from the converter
to the load (and resulting series inductance), the topology and locations of
load elements if there are multiple parallel loads and the nature of the loads.
For switching loads such as CPU’s and logic, this last item recommends
that small bypass capacitors be placed directly at the load. Very high clock
speeds suggest smaller caps unless the instantaneous current changes are
high. If the load is a precision high-gain linear section, additional filtering and
shielding may be needed.
Many applications will need no additional capacitance. However, if more
capacitance is indicated, observe these factors:
1. Understand the noise-reduction objective. Are you improving the switching
threshold of digital logic to reduce errors? (This may need only a small
amount of extra capacitance). Or do you need very low noise for a preci-
sion linear “front end”?
½½½½½½
½½½½½½½½½½½
½½½½½½½½½½½½½½½½
½½½½½½½½
½½½½½
½½½½½½
½½½½½½½½½½
½½½½½½½½
½½½½½½½
½½½½½½
½½½½½½½
½½½½½½
½½½½½½
½½½½½½
½½½½½½½½½½
2. Use just enough capacitance to achieve your objective. Additional capaci-
tance trades off increasing instability (actually adding noise rather than
reducing it), poor settling response, possible ringing or outright oscillation
by the converter. Excessive capacitance may also disable the hiccup
autorestart. Do not exceed the maximum output capacitance specification.
Figure 4. On/Off Control With An External Transistor ½
5
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