®
®
DAC-HF Series
Ultra-Fast, 8/10/12-Bit
Digital-to-Analog Converters
INNOVATION and EXCELLENCE
FEATURES
•
•
•
•
•
•
•
8, 10 and 12-Bit resolutions
Settling times to 25ns
±20ppm/°C max. gain tempco
Unipolar or bipolar operation
Current output
Internal feedback resistors
High-reliability MIL-STD-883 models
GENERAL DESCRIPTION
The DAC-HF Series of hybrid DAC’s are ultra high-speed,
current output devices. They incorporate state-of-the-art
performance in a miniature package, achieving maximum
output settling times of 25ns for the 8 and 10-bit models and
50ns for the 12-bit model. They can be used to drive a
resistor load directly for up to ±1V output or a fast operational
ampifier (such as DATEL’s AM-500) for higher voltage outputs
with sub-microsecond settling times. A tapped feedback
resistor and a bipolar offset resistor are included internally to
give five programmable output voltage ranges with an
external operational amplifier.
INPUT/OUTPUT CONNECTIONS, DAC-HF12B
The DAC-HF design combines proven hybrid construction
techniques with advanced circuit design to realize high-speed
current switching. The design incorporates fast PNP current
switches driving a low-impedance R-2R thin-film ladder
network. The nichrome thin-film resistor network is
deposited by electron beam evaporation on a lowcapacitance substrate to assure high-speed performance.
The resistors are then functionally trimmed by laser for
optimum linearity.
+15V SUPPLY
24
PIN
FUNCTION
PIN
FUNCTION
1
2
3
4
5
6
7
8
9
10
11
12
BIT 1 (MSB)
BIT 2
BIT 3
BIT 4
BIT 5
BIT 6
BIT 7
BIT 8
BIT 9 *
BIT 10 *
BIT 11 *
BIT 12 (LSB) *
24
23
22
21
20
19
18
17
16
15
14
13
+15V SUPPLY
GROUND
–15V SUPPLY
REFERENCE OUT
BIPOLAR OFFSET
10V RANGE
OUTPUT
20V RANGE
REFERENCE IN
GROUND
GROUND
GROUND
* See note in Figure 1
GROUNDS
13 14 15 23
–15V SUPPLY
22
–10V
REFERENCE
21
REFERENCE OUT
(–10.05V±0.05V)
20
BIPOLAR
OFFSET
4kW
2kW
THIN-FILM R-2R
LADDER NETWORK
2kW
17 20V RANGE
19 10V RANGE
18 OUTPUT
FAST PNP
CURRENT SWITCHES
PIN 1
BIT 1
MSB
2 3 4
2 3 4
5
5
6
6
8 9 10 11 12
8 9 10 11 12
* * * *
LSB
DIGITAL INPUTS
REFERENCE
CONTROL
CIRCUIT
16 REFERENCE IN
7
7
* FOR DAC-HF10B, PINS 11 & 12 ARE NO CONNECTION
FOR DAC-HF8B, PINS 9, 10, 11 & 12 ARE NO CONNECTION
Figure 1. Functional Block Diagram
®
®
DAC-HF Series
TECHNICAL NOTES
ABSOLUTE MAXIMUM RATINGS, ALL MODELS
Positive Supply, Pin 24
Negative Supply, Pin 22
Digital Input Voltage, Pins 1–12
Lead Temperature (soldering, 10s)
1. Proper operation of the DAC-HF Series converters is
dependent on good board layout and connection practices.
Bypass supplies as shown in the connection diagrams.
Mount bypass capacitors close to the converter, directly to
the supply pins where possible.
+18V
–18V
+15V
300°C
FUNCTIONAL SPECIFICATIONS
(Typical at +25°C and ±15V supplies unless otherwise noted.)
DESCRIPTION
INPUTS
Resolution, Bits
Coding, Unipolar Output
Coding, Bipolar Output
Input Logic Level, Bit ON ("1")
Input Logic Level, Bit OFF ("0")
8B
10B
12B
8
10
12
Straight binary
Offset binary
+2.0V to +5.5V at +40μA
0V to +0.8V at –2.6mA
PERFORMANCE
Nonlinearity Error, max.
TMIN to TMAX
Differential Nonlinearity Error, max.
TMIN to TMAX
Monotonicity
Gain Tempco, max.
Offset Tempco, Bipolar, max.
Zero Tempco, max.
Settling Time, ns max. ➂
Power Supply Sensitivity
±0.012%
±0.024%
±0.012%
±0.024%
Guaranteed over oper. temp. range
±20ppm/°C
±10ppm/°C of FSR ➁
±1.5ppm/°C of FSR ➁
25
25
50
±0.01%/% Supply
OUTPUTS
Output
Output
Output
Output
Current Range, Unipolar
Current Range, Bipolar
Compliance Voltage
Voltage Ranges ➀
Output Resistance
Output Capacitance
Output Leakage Current, All Bits OFF
0 to +5mA
±2.5mA
±1.2V
0 to –5V
0 to –10V
±2.5V
±5V
±10V
400 Ohms ±10%
15pF
15nA
±15V ±0.5V
40mA
45mA
17mA
17mA
50mA
17mA
PHYSICAL ENVIRONMENTAL
Operating Temperature Range, Case
Storage Temperature Range
Package Type
Weight
0°C to +70°C (BMC)
–55°C to +125°C (BMM, 883)
–65°C to +150°C
24-pin ceramic DDIP
0.22 ounces (6.3 grams)
Footnotes
➀ With external operational amplifier.
➁ FSR is Full Scale Range, or the difference between minimum
and maximum output values.
➂ Full-scale current change to ±1LSB with 400Ω load.
3. When the converter is configured for voltage output with an
external operational amplifier, keep the leads from the
converter to the output amplifier as short as possible.
4. The high-speed current switching technique used in the
DAC-HF Series inherently reduces the amplitude and
duration of large transient spikes at the output (“glitches”).
The most severe glitches occur at half-scale, the major
carry transition from 011 … 1 to 100 … 0 or vice versa. At
this time, a skewing of the input codes can create a
transition state code of 111 … 1. The duration of the
“transition state code” is dependent on the degree of
skewing, but its effect is dependent on the speed of the
DAC (an ultra-fast DAC will respond to these brief
spurious inputs to a greater degree than a slow DAC).
Minimize the effects of input skewing by using a highspeed input register to match input switching times. The
input register recommended for use with the DAC-HF is
easily implemented with two Texas Instruments
SN74S174 hex D-type flip-flops. This register will reduce
glitches to a very low level and ensure fast output settling
times.
5. Test the DAC-HF using a low-capacitance test probe (such
as a 10X probe). Take care to assure the shortest
possible connection between probe ground and circuit
ground. Long probe ground leads may pick up
environmental E.M.I. causing artifacts on the scope
display, i.e., signals that do not originate at the unit under
test.
POWER REQUIREMENTS
Supply Voltages
Positive Quiescent Current, max.
Negative Quiescent Current, max.
2. Use of a ground plane is particularly important in highspeed D/A converters as it reduces high-frequency noise
and aids in decoupling the digital inputs from the analog
output. Avoid ground loop problems by connecting all
grounds on the board to the ground plane. The remainder
of the ground plane should include as much of the circuit
board as possible.
6. Passive components used with the DAC-HF may be as
indicated here: 0.1μF and 1μF bypass capacitors should
be ceramic type and tantalum type respectively; the 400Ω
output load is a ±0.1%, 10ppm/°C, metal-film type;
adjustment potentiometers are ceremet types; other
resistors may be ±10% carbon composition types.
7. Output voltage compliance is ±1.2V to preserve the
linearity of the converter. In the bipolar mode, the DAC-HF
can be operated with no load to give an output voltage of
±1.0V. In the unipolar mode, the load resistance must be
less than 600Ω to give less than +1.2V output. The
specified output currents of 0 to +5mA and ±2.5mA are
measured into a short circuit or an operational amplifier
summing junction.
®
®
DAC-HF Series
CALIBRATION PROCEDURE
Table 1. 12-Bit Unipolar Output Coding
ANALOG OUTPUT
UNIPOLAR
INPUT CODING
SCALE
STRAIGHT BINARY 0 to 1V F.S. 0 to –5V F.S. 0 to –10V F.S.
Unipolar Output Current
1. Connect the converter as shown in Figure 2.
2. Set all inputs low and adjust the ZERO ADJUST
potentiometer for a reading of 0V at the output.
3. Set all inputs high and adjust the GAIN ADJUST
potentiometer for a reading of –F.S. + 1LSB (See Table 1).
Bipolar Output Current
–F.S. + 1LSB
–3/4F.S.
–1/2F.S.
–1/4F.S.
–1LSB
0
+0.9998V
+0.7500V
+0.5000V
+2.5000V
+0.0002V
0.0000V
–4.9988V
–3.7500V
–2.5000V
–1.2500V
–0.0012V
0.0000V
2. Set all inputs low and adjust the OFFSET ADJUST and
LOAD potentiometer for an output reading of +F.S. (See
Table 2).
3. Set all inputs high and adjust the GAIN ADJUST potentiometer for an output reading of –F.S. + 1LSB (See Table 2).
+15V
+
1µF
BIPOLAR
SCALE
–F.S. + 1LSB
–1/2F.S.
–1LSB
0
+1/2F.S.
+F.S. – 1LSB
+F.S.
ANALOG OUTPUT
INPUT CODING
OFFSET
±0.5V F.S. ±2.5V F.S. ±5V F.S.
BINARY
1111 1111 1111
1100 0000 0000
1000 0000 0001
1000 0000 0000
0100 0000 0000
0000 0000 0001
0000 0000 0000
+0.4998V
+0.1250V
+0.0002V
0.0000V
–0.1250V
–0.4998V
–0.5000V
–2.4988V
–1.2500V
–0.0012V
0.0000V
+1.2500V
+2.4988V
+2.5000V
–4.9976V
–2.5000V
–0.0024V
0.0000V
+2.5000V
+4.9976V
+5.0000V
19
1
17
OUTPUT
I OUT
18
FEEDBACK
OUTPUT VOLTAGE
CONNECTIONS
RANGE
0 to –5V
0 to –10V
±2.5V
±5V
±10V
100W
200W
DAC-HF
LOAD
(444W NOMINAL)
(FOR 0 TO ±0.5V FS)
OFFSET
ADJUST
20
370W
21
100W
–9.9951V
–5.0000V
–0.0049V
0.0000V
+5.0000V
+9.9951V
+10.0000V
CONNECT THESE
PINS TOGETHER
PIN 19
PIN 19
PIN 19
PIN 19
PIN 17
PIN 17 to PIN 18 / PIN 20 to PIN 23
PIN 20 to PIN 23
PIN 17 to PIN 18 / PIN 20 to PIN 18
PIN 20 to PIN 18
PIN 20 to PIN 18
In all programmable output ranges, pin 18 connects to
external operational amplifier inverting input.
GAIN
ADJUST
16
15
14
12
4k = 0.1%
13
22
23
–15V
20
BIPOLAR
OFFSET
21
REF OUT
(–10V = 2%)
19
2kΩ FEEDBACK
(10V RANGE)
17
4kΩ FEEDBACK
(20V RANGE)
1µF
0.1µF
+
Figure 3. Bipolar Current Output Connections
2k
2k
+15V
18 OUTPUT
+
0.1µF
1µF
400Ω, ±10%
5mA
+15V
BIT 1
19
1
23 GROUND
ZERO
ADJUST
25kW
24
2MW
17
–15V
Figure 4. Equivalent Output Circuit
OUTPUT
18
I OUT
400W LOAD
(FOR 0 TO
+1V FS)
20
21
DAC-HF
15
2V/DIV
GAIN
ADJUST
16
2V/DIV
100W
14
12
BIT 12
±10V F.S.
Table 3. Programmable Output Range Pin Connections
24
BIT 1
BIT 12
–9.9976V
–7.5000V
–5.0000V
–2.5000V
–0.0024V
0.0000V
Table 2. 12-Bit Bipolar Output Coding
1. Connect the converter as shown in Figure 3.
0.1µF
1111 1111 1111
1100 0000 0000
1000 0000 0000
0100 0000 0000
0000 0000 0001
0000 0000 0000
13
22
23
–15V
1µF
0.1µF
+
Figure 2. Unipolar Current Output Connections
50nsec/DIV
50nsec/DIV
DAC-HF with AM-500, ±5V output full scale (10V) step
Figure 5. Voltage Output Waveforms
®
®
DAC-HF Series
APPLICATIONS
+ 1 5 V
0 .1 µ F
+
*
F E E D B A C K ; S e e p r o g r a m m a b le
o u tp u t r a n g e c o n n e c tio n s , T a b le 3 .
1 µ F
*
2 4
B IT 1
*
1 9
1
+
0 .1 µ F
2 4
B IT 1
+ 1 5 V
1 µ F
*
1 9
1
1 7
F E E D B A C K ; S e e p r o g r a m m a b le
o u tp u t r a n g e c o n n e c tio n s , T a b le 3 .
1 7
4
1 8
A M -5 0 0
1 0
2
1 8
O U T P U T
D A C -H F
7 5 0 k
1 0 0 Ω
G A IN
A D J U S T
R =
1 4
B IT 1 2
2 2
2 3
1 5 V
0 .1 µ F
+
1 0 0 Ω
1 µ F
1 6
R F E E D B A C K x 4 0 0
R F E E D B A C K + 4 0 0
1 5
1 4
OUTPUT
STEP
TYPICAL SETTLING
TIME TO 1LSB
20V
10V
5V
300ns
200ns
150ns
B IT 1 2
1 3
1 5 V
1
OUTPUT
STEP
TYPICAL SETTLING
TIME TO 1LSB
20V
10V
5V
2μs
600ns
400ns
Figure 7. Unipolar Fast Voltage Output Circuit
ORDERING INFORMATION
1.31 MAX.
(33.27)
Dimension Tolerances (unless otherwise indicated):
2 place decimal (.XX) ±0.010 (±0.254)
3 place decimal (.XXX) ±0.005 (±0.127)
0.80 MAX.
(20.32)
1 µ F
+
MECHANICAL DIMENSIONS INCHES (mm)
13
2 2
2 3
0 .1 µ F
Figure 6. Unipolar Ultra-Fast Voltage Output Circuit
24
2 0 k Ω
G A IN
A D J U S T
1 2
1 3
1 5 V
O F F S E T
A D J U S T
1 5 V
1 5
1
5
2 1
D A C -H F
Z E R O
A D J U S T
2 0 k 9
R
1 6
1 2
2 0
+ 1 5 V
2 1
O U T P U T
7
3
2 0
6
A M -4 5 2
5
Lead Material: Kovar alloy
Lead Finish: 50 microinches (minimum) gold plating
over 100 microinches (nominal) nickel plating
12
0.100 TYP.
(2.540)
1.100
(27.940)
0.235 MAX.
(5.969)
MODEL
OPERATING
TEMP. RANGE
BITS
DAC-HF8BMC
DAC-HF8BMM
DAC-HF8/883 ➀
DAC-HF10BMC
DAC-HF10BMM
DAC-HF10/883 ➀
DAC-HF12BMC
DAC-HF12BMM
DAC-HF12/883 ➀
0 to +70°C
–55 to +125°C
–55 to +125°C
0 to +70°C
–55 to +125°C
–55 to +125°C
0 to +70°C
–55 to +125°C
–55 to +125°C
8
8
8
10
10
10
12
12
12
0.200 MAX.
(5.080)
+0.002
0.010 –0.001
(0.254)
0.190 MAX.
(4.826)
0.018 ±0.002
(0.457)
®
0.100
(2.540)
0.040
(1.016)
SEATING
PLANE
0.025
(0.635)
0.600 ±0.010
(15.240)
®
0.100
(2.540)
USA:
Tucson (Az), Tel: (800) 547 2537, email: [email protected]
Portland (OR), Tel: 971 206 2800, email: [email protected]
Canada: Toronto, Tel: (905) 944 2850, email: [email protected]
United Kingdom: Milton Keynes, Tel: +44 (0)1908 615232,
email: [email protected]
C&D Technologies, Inc.
11 Cabot Boulevard, Mansfield, MA 02048-1151 U.S.A.
Tel: (508) 339-3000
(800) 233-2765 Fax: (508) 339-6356
www.cd4power.com
email: [email protected]
ISO 9001 REGISTERED
DS-0132C 6/2007
C&D Technologies, Inc. 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. Specifications are subject to change without notice.
France: Montigny Le Bretonneux, Tel: +33 (0)1 34 60 01 01,
email: [email protected]
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Website: www.cd4power.jp
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