AD7937AR-REEL Analog Devices Inc, AD7937AR-REEL Datasheet

no-image

AD7937AR-REEL

Manufacturer Part Number
AD7937AR-REEL
Description
IC DAC 12BIT DUAL 8+4 24-SOIC
Manufacturer
Analog Devices Inc
Datasheet

Specifications of AD7937AR-REEL

Rohs Status
RoHS non-compliant
Settling Time
1µs
Number Of Bits
12
Data Interface
Parallel
Number Of Converters
2
Voltage Supply Source
Single Supply
Power Dissipation (max)
24mW
Operating Temperature
-40°C ~ 85°C
Mounting Type
Surface Mount
Package / Case
24-SOIC (7.5mm Width)
a
GENERAL DESCRIPTION
The AD7937 contains two 12-bit current output DACs on one
monolithic chip. A separate reference input is provided for each
DAC. The dual DAC saves valuable board space, and the mono-
lithic construction ensures excellent thermal tracking. Both DACs
are guaranteed 12-bit monotonic over the full temperature range.
The AD7937 has a 2-byte (eight LSBs, four MSBs) loading
structure. It is designed for right-justified data format. The control
signals for register loading are A0, A1, CS, WR, and UPD. Data
is loaded to the input registers when CS and WR are low. To
transfer this data to the DAC registers, UPD must be taken
low with WR.
Added features on the AD7937 include an asynchronous CLR
line which is very useful in calibration routines. When this is
taken low, all registers are cleared. The double buffering of the
data inputs allows simultaneous update of both DACs. Also,
each DAC has a separate AGND line. This increases the device
versatility; for instance, one DAC may be operated with AGND
biased while the other is connected in the standard configuration.
The AD7937 is manufactured using the Linear Compatible
CMOS (LC
microprocessors and accepts TTL, 74HC, and 5 V CMOS logic
level inputs.
2
MOS) process. It is speed compatible with most
PRODUCT HIGHLIGHTS
1. DAC-to-DAC Matching
2. Small Package Size
3. Wide Power Supply Tolerance
UPD
CLR
WR
CS
A1
A0
(8+4) Loading Dual 12-Bit DAC
Since both DACs are fabricated on the same chip, precise
matching and tracking is inherent. Many applications that are
not practical using two discrete DACs are now possible.
Typical matching: 0.5%.
The AD7937 is packaged in a small 24-lead SOIC.
The device operates on a 5 V V
this nominal figure. All specifications are guaranteed over
this range.
CONTROL
AD7937
LOGIC
V
FUNCTIONAL BLOCK DIAGRAM
DD
DB7–DB0
INPUT REG
INPUT REG
DAC A MS
DAC B MS
DD
DAC A REGISTER
DAC B REGISTER
4
4
, with ± 10% tolerance on
DGND
DAC A
DAC B
12
12
INPUT REG
INPUT REG
DAC A LS
DAC B LS
AD7937
8
8
LC
2
MOS
AGNDA
R
R
I
V
V
I
AGNDB
OUTA
OUTB
FBA
FBB
REFA
REFB

Related parts for AD7937AR-REEL

AD7937AR-REEL Summary of contents

Page 1

GENERAL DESCRIPTION The AD7937 contains two 12-bit current output DACs on one monolithic chip. A separate reference input is provided for each DAC. The dual DAC saves valuable board space, and the mono- lithic construction ensures excellent thermal tracking. ...

Page 2

AD7937–SPECIFICATIONS Parameter A Version ACCURACY Resolution 12 ± 1 Relative Accuracy ± 1 Differential Nonlinearity ± 6 Gain Error 2 Gain Temperature Coefficient ; ∆Gain/∆Temperature ± 5 Output Leakage Current I 5 OUTA OUTB 10 REFERENCE INPUT ...

Page 3

... Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Model Temperature Range AD7937AR –40°C to +85°C AD7937BR –40°C to +85°C CAUTION ESD (electrostatic discharge) sensitive device ...

Page 4

AD7937 PIN FUNCTION DESCRIPTIONS Pin Mnemonic Description 1 AGNDA Analog Ground for DAC Current output terminal of DAC A. OUTA 3 R Feedback resistor for DAC A. FBA 4 V Reference input to DAC A. REFA CS ...

Page 5

UNIPOLAR BINARY OPERATION (2-QUADRANT MULTIPLICATION) Figure 4 shows the circuit diagram for unipolar binary operation. With an ac input, the circuit performs 2-quadrant multiplication. The code table for Figure 4 is given in Table II. Operational amplifiers A1 and A2 ...

Page 6

AD7937 SEPARATE AGND PINS The DACs in the AD7937 have separate AGND lines taken to pins AGNDA and AGNDB on the package. This increases the applications versatility of the part. Figure example of this. DAC A is ...

Page 7

APPLICATION HINTS Output Offset: CMOS D/A converters in circuits such as Fig- ures 4 and 5 exhibit a code-dependent output resistance which in turn can cause a code-dependent error voltage at the output of the amplifier. The maximum amplitude of ...

Page 8

AD7937 PIN 1 0.0118 (0.30) 0.0040 (0.10) OUTLINE DIMENSIONS Dimensions shown in inches and (mm). 24-Lead Small Outline SOIC (R-24) 0.6141 (15.60) 0.5985 (15.20 0.2992 (7.60) 0.2914 (7.40) 0.4193 (10.65 0.3937 (10.00) 0.1043 (2.65) 0.0926 (2.35) ...

Related keywords