DAC-HF
Ultra-Fast, 8ꢁ10ꢁ12-Bit Digital-to-Analog Converters
FEATURES
8, 10 and 12-Bit resolutions
Settling times to 25ns
20ppmꢁ/C max. gain tempco
Unipolar or bipolar operation
Current output
Internal feedback resistors
High-reliability MIL-STD-883 models
PRODUCT OVERVIEW
INPUT/OUTPUT CONNECTIONS
The DAC-HF Series of hybrid DAC’s are ultra
high-speed, current output devices. They incorpo-
rate state-of-the-art performance in a miniature
The DAC-HF design combines proven hybrid
construction techniques with advanced circuit
design to realize high-speed current switching.
PIN FUNCTION
PIN FUNCTION
1
BIT 1 (MSB)
BIT 2
24
23
22
21
20
19
18
17
16
15
14
13
+15V SUPPLY
2
GROUND
package, achieving maximum output settling times The design incorporates fast PNP current switches
3
BIT 3
–15V SUPPLY
REFERENCE OUT
BIPOLAR OFFSET
10V RANGE
OUTPUT
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 1ꢀ 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.
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.
4
BIT 4
5
BIT 5
6
BIT 6
7
BIT 7
8
BIT 8
20V RANGE
REFERENCE IN
GROUND
9
BIT 9 *
BIT 10 *
BIT 11 *
BIT 12 (LSB) *
10
11
12
GROUND
GROUND
* See note in Figure 1
BLOCK DIAGRAM
GROUNDS
13 14 15 23
+15V SUPPLY
24
–15V SUPPLY
22
REFERENCE OUT
(–10.05V±0.05V)
–10V
REFERENCE
21
20
4k
BIPOLAR
OFFSET
2k
2k
THIN-FILM R-2R
17 20V RANGE
19 10V RANGE
18 OUTPUT
LADDER NETWORK
REFERENCE
CONTROL
CIRCUIT
FAST PNP
CURRENT SWITCHES
16 REFERENCE IN
PIN
BIT
1
1
9 10 811 127
9 170 11612
6
5
4
3
2
8
5
4
3
2
*
*
*
*
MSB
LSB
FOR DAC-HF10B, PINS 11 & 12 ARE NO CONNECTION
FOR DAC-HF8B, PINS 9, 10, 11 & 12 ARE NO CONNECTION
DIGITAL INPUTS
*
Figure 1. DAC-HF Functional Block Diagram
DATEL, Inc. 11 Cabot Boulevard, Mansfield, MA 02048-1151 USA
•
Tel: (508) 339-3000
•
www.datel.com
•
e-mail: help@datel.com
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