WM2637
Dual 10-Bit Serial Input Voltage Output DAC
with Internal Reference
Production Data, Rev 1.0, July 1999
FEATURES
•
•
•
•
•
Dual 10-bit voltage output DAC
Single 2.7V to 5.5V supply
DNL
±
0.1 LSBs, INL
±
0.4 LSBs
Internal programmable voltage reference
Low power consumption:
•
5.5 mW, slow mode - 5V supply
•
3.3 mW, slow mode - 3V supply
TM
TM
TMS320, (Q) SPI , and Microwire compatible serial
interface
Programmable settling time of 1µ s or 3.5µ s typical
µ
µ
Power down mode 10nA
DESCRIPTION
The WM2637 is a dual 10-bit voltage output, resistor string, digital-
to-analogue converter. A software controlled power down mode is
provided that reduces current consumption to 10nA.
The WM2637 features an internal programmable voltage reference
simplifying overall system design. A reference voltage may also be
supplied externally.
The device has been designed to interface efficiently to industry
standard microprocessors and DSPs, including the TMS320
family. The WM2637 is programmed with a 16-bit serial word
comprising of a latch address, mode DAC control bits and DAC or
control data.
Excellent performance is delivered with a typical DNL of 0.1 LSBs.
The programmable settling time allows the designer to optimize
speed versus power consumption. The output stage is buffered by
a x2 gain near rail-to-rail amplifier.
The device is available in an 8-pin SOIC package ideal for space-
critical applications. Commercial temperature (0° to 70°C) and
industrial temperature (-40° to 85
°C)
variants are supported.
•
•
•
APPLICATIONS
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•
•
•
•
•
•
Battery powered test instruments
Digital offset and gain adjustment
Battery operated/remote industrial controls
Machine and motion control devices
Wireless telephone and communication systems
Speech synthesis
Arbitrary waveform generation
ORDERING INFORMATION
DEVICE
WM2637CD
WM2637ID
TEMP. RANGE
0° to 70°C
-40° to 85°C
PACKAGE
8-pin SOIC
8-pin SOIC
BLOCK DIAGRAM
VDD
(8)
TYPICAL PERFORMANCE
0.2
5V = VDD, V
REF
= External, Speed = Slow mode, Load = 10k/100pF
0.15
c
REFERENCE
OUTPUT BUFFER
WITH OUPUT
ENABLE
REF(6)
X1
1.024V/2.048V
SELECTABLE
REFERENCE
0.1
0.05
DNL - LSB
(4) OUTA
(7) OUTB
2-BIT
REFERENCE
SELECT
LATCH
REFERENCE
INPUT
BUFFER
X1
0
DAC
OUTPUT
BUFFER
X2
DIN (1)
16-BIT
SHIFT
REGISTER
AND
CONTROL
LOGIC
10-BIT
DAC A
LATCH
-0.05
REFERENCE
INPUT BUFFER
X1
SCLK (2)
-0.1
DAC
OUTPUT
BUFFER
X2
NCS (3)
10-BIT
DAC B
HOLDING
LATCH
10-BIT
DAC B
LATCH
-0.15
-0.2
0
2-BIT
CONTROL
LATCH
POWERDOWN/
SPEED
CONTROL
256
512
DIGITAL CODE
767
1023
POWER-ON
RESET
WM2637
(5)
AGND
WOLFSON MICROELECTRONICS LTD
Lutton Court, Bernard Terrace, Edinburgh, EH8 9NX, UK
Tel: +44 (0) 131 667 9386
Fax: +44 (0) 131 667 5176
Email: sales@wolfson.co.uk
http://www.wolfson.co.uk
Production Data
contains final specifications
current on publication date. Supply of products
conforms to Wolfson Microelectronics' Terms
and Conditions.
Last printed 15/07/99 15:56
©1999
Wolfson Microelectronics Ltd
.
WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
