WM2639 Datasheet, PDF (1/10 Pages) Wolfson Microelectronics plc – 12-Bit Parallel Input Voltage Output DAC with Internal Reference

WM2639
12-Bit Parallel Input Voltage Output DAC
with Internal Reference
Production Data, July 1999, Rev 1.0
FEATURES
• 12-bit voltage output DAC
• Single supply 2.7V to 5.5V operation
• DNL ±0.3 LSBs, INL ±1.2 LSBs
• Internal programmable voltage reference
• Settling time 1µs typical
• 12-bit microprocessor compatible interface
• Power down mode 10nA
APPLICATIONS
• 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
• Mass storage devices
DESCRIPTION
The WM2639 is a 12-bit voltage output, resistor string, digital-to-
analogue converter. A hardware controlled power down mode is
provided that reduces current consumption to 10nA. The device
has been designed to interface efficiently to industry standard
microprocessors and DSPs.
The WM2639 features an internal programmable voltage reference
simplifying overall system design. The reference voltage can also
be supplied externally.
Excellent performance is delivered with a typical DNL of 0.3 LSBs
and typical INL of 1.2 LSBs. The output stage is buffered by a x2
gain near rail-to-rail amplifier, which features a Class A output
stage (slow mode, Class AB). The 12 data bits are double buffered
enabling the output to be asynchronously updated under hardware
control. The settling time of the DAC is software programmable to
allow the designer to optimise speed versus power dissipation.
The device is available in a 20-pin TSSOP package. Commercial
temperature (0° to 70°C) and Industrial temperature (-40° to 85°C)
variants are supported.
ORDERING INFORMATION
DEVICE
WM2639CDT
WM2639IDT
TEMP. RANGE
0° to 70°C
-40° to 85°C
PACKAGE
20-pin TSSOP
20-pin TSSOP
BLOCK DIAGRAM
REF(12)
REFERENCE
OUTPUT BUFFER
WITH OUPUT
ENABLE
X1
1.024V/2.048V
SELECTABLE
REFERENCE
VDD
(11)
D[0-11]
(19,20, 1-10)
NWE (17)
NCS (18)
REG (15)
2-BIT
REFERENCE
SELECT
LATCH
12-BIT
INPUT
REGISTER
data
12-BIT
DAC
LATCH
2-BIT
CONTROL
LATCH
REFERENCE
INPUT
BUFFER
X1
POWERDOWN
CONTROL
DAC
OUTPUT
BUFFER
X2
POWER-ON
RESET
(14)
GND
(16)
NLDAC
WM2639
(13) OUT
TYPICAL PERFORMANCE
1
5V = VDD, VREF
0.8
0.4
0.2
-0.2
-0.4
-0.8
-1
512
1024
2048
2559
3583
4095
WOLFSON MICROELECTRONICS LTD
Lutton Court, Bernard Terrace, Edinburgh, EH8 9NX, UK
Tel: [phone]
Fax: [phone]
Email: [e-mail]
http://www.wolfson.co.uk
Production Data contain final specifications
current on publication date. Supply of products
conforms to Wolfson Microelectronics’ Terms
and conditions..
Master 15/07/99 15:02
©1999 Wolfson Microelectronics Ltd.