INNOVATION and EX C ELL E N C E
Figure 1. Simplifi ed Schematic
NEW
DATEL, Inc., Mansfi eld, MA 02048 (USA) Tel: (508)339-3000, (800)233-2765 Fax: (508)339-6356 Email: sales@datel.com Internet: www.datel.com
+LOAD
+LOAD
FAULT
LOAD
LOAD
BUFFER
AMPLIFIER
+5 VOLT
SUPPLY
+5 VOLT
RETURN
CONTROL
VOLTAGE IN (+)
CONTROL
VOLTAGE IN ()
ISOLATION
AMPLIFIER
ISOLATED
DC/DC
CONVERTER
ISOLATED
DC/DC
CONVERTER
AMPLIFIER
CURRENT
DRIVER
ERROR
DETECTION
+
The DTL22A is an isolated (500Vdc), near-ideal (Z
IN
= Z
OUT
10M
), analog/
voltage-controlled current sink. Its 0-20A output/load current is straightforwardly
"programmed" by applying a 0-10V input. The control signal can be generated by
circuits as simple as the wiper of a trimpot or as sophisticated as programmable logic
controllers (PLC's) or analog-output computer I/O boards (D/A boards). The DTL22A
supports any combination of I
OUT
= 0-20 Amps and V
OUT
= 2.5-50 Volts. Its thermally
effi cient, metal package, when properly heat sunk, can dissipate output/load power
up to 100 Watts.
The easy-to-use DTL22A is an excellent building block for low-cost, fully fl exible,
power-supply (AC/DC or DC/DC) or power-component (MOSFET's, diodes, etc.) test
and burn-in applications. It is accurate (5mA offset error, 1% overall accuracy),
fast (200sec full-scale step response), and capable of impressive resolution. If it is
controlled with a 12-bit, 0-10V D/A converter, for example, one LSB (least signifi cant
bit) of the D/A corresponds to a 5mA change in the DTL22A's output/load current.
The DTL22A is packaged in a small (2" x 2" x 0.5"), thermally effi cient metal
package incorporating an aluminum baseplate with threaded inserts. It is powered by
a single +5V supply and draws a mere 150mA.
The DTL22A has an output compliance voltage of 2.5-50 Volts. Should the
output/load voltage drop below the 2.5V required for proper biasing, an internal
monitoring circuit activates the DTL22A's output Fault line. See DATEL's DTL22A-LC
for compliance voltages as low as 0.6V.
The DTL22A and other electronic loads, controller boards, and software from
DATEL are outstanding building-block components for power-supply burn-in and test
systems. They are extremely reliable, cost-effective solutions that enable you to
quickly confi gure impressively accurate systems.
Features
Applications
0-10V input/control voltage
0-20A output/load current
2.5-50V output compliance voltage
0-100W output/load power
10M
output impedance
500Vdc isolation
1% accuracy under all conditions
200sec full-scale step response
2" x 2", shielded metal package
Operate in parallel for higher power
Power-supply test and characterization
Static/dynamic power-supply burn-in
Power-resistor substitution
Real-time load simulation
Capacitor discharge testing
DTL Series
DTL22A Model
Voltage-Controlled, 20 Amp
100 Watt, Electronic Loads
DTL Series
Pin
Function P51
Pin
Function P51
1
+5 Volt Supply
7
Control Voltage In ()
2
+5
Volt
Return
8
Load
3
Fault
9
Load
4
No
Pin
10
+Load
5
Control Voltage In (+)
11
+Load
6
No
Pin
Performance Specifi cations and Ordering Guide
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
Input
Output
DTL
22
DATEL
Electronic Load
Voltage Range:
22 = 2.5 to 50V
A
A-Series
High Reliability
T E M P E R A T U R E D E R A T I N G
11
8
9
10
1
2
4
3
5
6
7
METAL CASE
ALUMINUM BASEPLATE
2.00
(50.80)
2.00
(50.80)
0.20 MIN
(5.08)
1.20
(30.48)
6 EQ. SP. @
0.200 (5.08)
1.800
(45.72)
1.640
(41.66)
1.640
(41.66)
0.50
(12.70)
0.060 0.002 DIA.
(1.524 0.051)
0.040 0.002 DIA.
(1.016 0.051)
#4-40 CLEAR THRU
(TYP. 4 PL)
BOTTOM VIEW
0.10
(2.54)
0.08
(2.03)
0.22
(5.59)
0.40
(10.16)
I/O Connections
Contact DATEL for Heat Sink information.
The horizontal axis of the above chart references the temperature of the DTL22A's
aluminum baseplate. The device can continually dissipate up to 100 Watts if the baseplate
is maintained at or below +50C. At +25C ambient temperature, with no heat sink or
supplemental air fl ow, the DTL22A can reliably dissipate a continuous 10 Watts.
2
Case C24
Control
Compliance
Voltage Impedance Current Resolution Voltage
Power
Package
Model
(Volts)
(Minimum)
(Amps)
(mA)
(Volts)
(Watts)
(Case,
Pinout)
DTL22A 0
to
+10 10M
0-20
5 2.5-50 0-100
C24,
P51
Typical at T
A
= +25C with nominal +5V supply voltage, unless noted.
Listed resolution (5mA) is for a typical application in which the DTL22A is controlled by a voltage
generated by a 12-bit D/A converter with a 0-10V output range. One LSB (least signifi cant bit) of the D/A
corresponds to 0.0244% (1/4096) of full scale (20 Amps), which equals approximately 5mA.
For proper operation, the unit's output/load voltage must remain within this range. Voltages greater than the listed
maximum can damage the device. Voltages less than the minimum provide insuffi cient bias for the output stage
and will result in unpredictable or no operation. See Output Compliance Voltage and the Fault Line for details.
Output P
o
wer/Load (W
atts)
Baseplate Temperature (
C)
100
90
80
70
60
50
40
30
20
10
0
10
20
30
40
50
60
70
80
90
100
1 0 0 W A T T , V O L T A G E - C O N T R O L L E D E L E C T R O N I C L O A D
DTL22A Model
Input
Control Voltage 0-10 Volts
Impedance 10M
, minimum
Output
Transfer Function I
OUT
(Amps) = 2V
IN
(Volts)
Current:
Range 0-20 Amps
Resolution
0.025%FS (5mA)
Offset Error
5mA, maximum
Gain Error 0.25%, maximum
Absolute Accuracy
1%, maximum
Voltage
2.5-50 Volts
Power
0-100 Watts
Impedance 10M
, minimum
Isolation Voltage:
Analog Input to Load 500Vdc, minimum
+5V Power to Input or Load 500Vdc, minimum
Any Pin to Case 500Vdc, minimum
Isolation Resistance 100M
, minimum
Fault Logic Levels:
Logic "1" (@ 150A) +3.5 Volts, minimum
Logic "0" (@ 1.6mA) +0.4 Volts, maximum
Dynamic Performance
Output Slew Rate 0.4A/sec, minimum
Output Settling Time
200sec
Dynamic Loading:
10mA to 20A 5kHz
0 to 20A 1kHz
Power Requirements
Power Supply Range (+V
CC
, Pin 1) +4.75-5.25 Volts (+5V nominal)
Power Supply Current 110mA typ., 150mA max.
Environmental
Operating Temperature
25 to +85C
Storage Temperature 40 to +85C
Humidity (Non-condensing) to 95%
Altitude Above Sea Level 10,000 feet
Physical
Dimensions 2" x 2" x 0.5" (51 x 51 x 12.7mm)
Shielding 6-sided
Case Material Tin-plated steel shell with
aluminum baseplate
Pin Material Brass, solder coated
Mounting Holes Through-hole spacers, #4-40 clearance
Weight 1.9 ounces (54 grams)
Listed resolution (5mA) is for a typical application in which the DTL22A is controlled by a voltage
generated by a 12-bit D/A converter with a 0-10V output range. One LSB (least signifi cant bit) of the D/A
corresponds to 0.0244% (1/4096) of full scale (20 Amps), which equals approximately 5mA.
Offset error is defi ned as the current sunk/sourced by the DTL22A's output, under any output-voltage
conditions, when the applied control voltage is 0 Volts.
Applies over all ranges/combinations of specifi ed output current, load voltage, output power,
operating temperature and V
CC
.
For proper operation, the DTL22A's output voltage must remain within the range listed. Voltages greater
than the listed maximum can damage the device. Voltages less than the listed minimum provide
insuffi cient bias for the output stage and will result in unpredictable or no operation. See Ouput
Compliance Voltage and the Fault Line for details.
The DTL22A can achieve its maximum output/load power only when its baseplate temperature is
properly maintained. See Temperature Derating.
Specifi ed for the full-scale step from 10mA to 20 Amps settling to 1% (200mA) of fi nal value. A
minimal loading of 10mA is recommended to achieve the fastest dynamic response.
Baseplate temperature. See Note 5 and Temperature Derating.
Supply Voltage (+V
CC
, Pin 1) 0.5 to +5.5 Volts
Input Voltage (Pin 4) 0.5 to 15 Volts
Output Reverse-Polarity Protection No protection
Output Overvoltage Protection No protection
Output Undervoltage Protection Yes (See Fault Line)
Case Temperature +85C
Storage Temperature (Ambient) 40 to +85C
Lead Temperature (Soldering, 10 sec.) +300C
Absolute Maximum Ratings
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 Specifi cations Table is not implied.
T E C H N I C A L N O T E S
3
Overview
The DTL22A is an analog programmable (0 to +10V control) current sink. It's
output/load current range is 0 to 20 Amps over a compliance voltage range
of 2.5 to 50 Volts and an output/load power range of 0 to 100 Watts. The
device's transfer function is as follows:
Iout (Amps) = 2V
IN
(Volts)
Examples: Control V
IN
= 1 Volt, I
OUT
= 2 Amps
Control
V
IN
= 10 Volts, I
OUT
= 20 Amps
In a typical power-supply test or burn-in application, the "positive" output and
"return" pins of the device under test (DUT) are connected to the DTL22A's
+Load (pins 10 and 11) and Load (pins 8 and 9) outputs.
1 0 0 W A T T , V O L T A G E - C O N T R O L L E D E L E C T R O N I C L O A D
Performance/Functional Specifi cations
Typical @ T
A
= +25C with nominal +5V supply voltage, unless noted.
DATEL makes no representation that the use of its products in the circuits described herein, or the use of other technical information contained herein, will not infringe upon existing or future patent rights. The descriptions contained herein
do not imply the granting of licenses to make, use, or sell equipment constructed in accordance therewith. Specifi cations are subject to change without notice. The DATEL logo is a registered DATEL, Inc. trademark.
DATEL (UK) LTD. Tadley, England Tel: (01256)-880444
DATEL S.A.R.L. Montigny Le Bretonneux, France Tel: 01-34-60-01-01
DATEL GmbH Mnchen, Germany Tel: 89-544334-0
DATEL KK Tokyo, Japan Tel: 3-3779-1031, Osaka Tel: 6-6354-2025
DATEL, Inc. 11 Cabot Boulevard, Mansfi eld, MA 02048-1151
Tel: (508) 339-3000 (800) 233-2765 Fax: (508) 339-6356
Internet: www.datel.com Email: sales@datel.com
DS-0497 5/01
ISO 9001 REGISTERED
INNOVATION and EX C ELL E N C E
Output Compliance Voltage and the Fault Line
For proper operation, the DTL22A's output/load voltage must always be
between 2.5 and 50 Volts. The device cannot be used to directly load
extremely low-voltage (such as 1.5V or 1.8V) power components or to
simulate a true short circuit (0 Volts). Voltages greater than 50V can damage
the device. Voltages <2.5V will result in insuffi cient biasing of the output
current source and consequently unpredictable or no operation. Accordingly,
we have installed an internal output/load-voltage monitoring circuit. If the
output/load voltage drops below 2.5V and the DTL22A's output is at risk of
becoming disabled, the Fault line activates.
The Fault line is an active-low function with an open-collector output (internal
10k
pull-up resistor to +5V). Under normal conditions, its output is high
(logic "1"). Under fault conditions (V
OUT
< 2.5V), its output drops to a logic "0."
There is no output/load-voltage monitoring circuit for voltages greater than
50V, and operation above 50V can damage the device.
An "offset supply" can be inserted between the DTL22A's Load output (pins
8 and 9) and the power device under test (DUT) to "translate" the DTL22A's
47.5V output/load voltage range. The offset supply must have adequate
current capabilities and be connected with the polarities indicated in Figure
2 below. Under no circumstances should the voltage across the DTL22A's
output be allowed to experience a polarity reversal.
If a 5V/20A offset supply is inserted as shown, the range of DUT voltages will
be 2.5 to +45 Volts. Such a confi guration can be used for true short-circuit
testing. A mechanical relay can be used to short the outputs of the DUT
while the offset supply ensures the DTL22A always sees at least 5 Volts
across its outputs.
Thermal Considerations
The DTL22A can reliably handle 100W loads if its aluminum baseplate tem-
perature is maintained at or below +50C. With no heat sinking or auxiliary
cooling, the device can only handle loads up to 10 Watts. Please refer to
the Temperature Derating Curve for additional information. DATEL's Electronic
Load Applications Engineers can assist you in developing heat-sink solutions
for your higher-power DTL22A applications. Contact us for details about our
DTL-HS100D12 heat sinks.
Figure 2. An "Offset Supply" Enables
True Short-Circuit Testing
4
Constant-Resistance Application
The DTL22A operates as a constant-current electronic load in its typical
confi guration. A constant-resistance mode of operation can be achieved as
follows:
The DTL22A has a high-impedance, isolated analog input that permits the
inputs to be connected directly across the load. The DTL22A sinks 20 Amps
for a 10 Volt full-scale input or I = 2
V
IN
. If you make V
IN
= V
LOAD
, (the
voltage across the load), then R = V
LOAD
/I = V
LOAD
/ (2
V
LOAD
) = 0.5 Ohms.
Consequently, the load looks like a 0.5 Ohm resistor.
Furthermore, if you make V
IN
= k
V
LOAD
by connecting a potentiometer or
resistive divider across the load, then R = V
LOAD
/ (2
k
V
LOAD
) = 0.5/k.
Adjusting the potentiometer effectively gives you an adjustable power resis-
tor. At k = 0.5, R = 1 Ohm; at k = 0.25, R = 2 Ohms, etc. The only
limitations you must observe are the maximum load voltage (50V) and the
maximum100 Watt power dissipation. A multiplying digtal-to-analog converter
or a digital potentiometer can also be used to effectively make a program-
mable resistance.
T E C H N I C A L N O T E S
+LOAD
DTL22A
LOAD
9
8
11
10
5V
+
+
DUT
SHORT
CIRCUIT
RELAY
DTL Series
1 0 0 W A T T , A N A L O G - C O N T R O L L E D E L E C T R O N I C L O A D
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