TL H 11015
ADC08231ADC08234ADC08238
8-Bit
2
m
s
Serial
IO
AD
Converters
with
MUX
Reference
and
TrackHold
December 1994
ADC08231 ADC08234 ADC08238 8-Bit 2 ms Serial I O
A D Converters with MUX Reference and Track Hold
General Description
The ADC08231 ADC08234 ADC08238 are 8-bit succes-
sive approximation A D converters with serial I O and con-
figurable input multiplexers with up to 8 channels The serial
I O is configured to comply with the NSC MICROWIRE
TM
serial data exchange standard for easy interface to the
COPS
TM
family of controllers and can easily interface with
standard shift registers or microprocessors
Designed for high-speed low-power applications the devic-
es are capable of a fast 2 ms conversion when used with a
4 MHz clock
All three devices provide a 2 5V band-gap derived reference
with guaranteed performance over temperature
A track hold function allows the analog voltage at the posi-
tive input to vary during the actual A D conversion
The analog inputs can be configured to operate in various
combinations of single-ended differential or pseudo-differ-
ential modes In addition input voltage spans as small as 1V
can be accommodated
Applications
Y
High-speed data acquisition
Y
Digitizing automotive sensors
Y
Process control monitoring
Y
Remote sensing in noisy environments
Y
Disk drives
Y
Portable instrumentation
Y
Test systems
Features
Y
Serial digital data link requires few I O pins
Y
Analog input track hold function
Y
4- or 8-channel input multiplexer options with address
logic
Y
On-chip 2 5V band-gap reference (
g
2% over tempera-
ture guaranteed)
Y
No zero or full scale adjustment required
Y
TTL CMOS input output compatible
Y
0V to 5V analog input range with single 5V power
supply
Y
Pin compatible with Industry-Standards ADC0831 4 8
Key Specifications
Y
Resolution
8 Bits
Y
Conversion time (f
C
e
4 MHz)
2 ms (Max)
Y
Power dissipation
20 mW (Max)
Y
Single supply
5 V
DC
(
g
5%)
Y
Total unadjusted error
g
LSB and
g
1 LSB
Y
Linearity Error (V
REF
e
2 5V)
g
LSB
Y
No missing codes (over temperature)
Y
On-board Reference
a
2 5V
g
1 5% (Max)
ADC08238 Simplified Block Diagram
TL H 11015 4
TRI-STATE
is a registered trademark of National Semiconductor Corporation
COPS
TM
microcontrollers and MICROWIRE
TM
are trademarks of National Semiconductor Corporation
C1995 National Semiconductor Corporation
RRD-B30M75 Printed in U S A
Absolute Maximum Ratings
(Notes 1
3)
If Military Aerospace specified devices are required
please contact the National Semiconductor Sales
Office Distributors for availability and specifications
Supply Voltage (V
CC
)
6 5V
Voltage at Inputs and Outputs
b
0 3V to V
CC
a
0 3V
Input Current at Any Pin (Note 4)
g
5 mA
Package Input Current (Note 4)
g
20 mA
Power Dissipation at T
A
e
25 C (Note 5)
800 mW
ESD Susceptibility (Note 6)
1500V
Soldering Information
N Package (10 sec )
260 C
TSSOP and SO Package (Note 7)
Vapor Phase (60 sec )
215 C
Infrared (15 sec )
220 C
Storage Temperature
b
65 C to
a
150 C
Operating Ratings
(Notes 2
3)
Temperature Range
T
MIN
s
T
A
s
T
MAX
ADC08231BIN ADC08231CIN
b
40 C
s
T
A
s
a
85 C
ADC08234BIN ADC08234CIN
ADC08238BIN ADC08238CIN
ADC08231BIWM ADC08231CIWM
ADC08234BIWM ADC08238BIWM
ADC08234CIWM ADC08238CIWM
ADC08234CIMF
Supply Voltage (V
CC
)
4 5 V
DC
to 6 3 V
DC
Electrical Characteristics
The following specifications apply for V
CC
e a
5 V
DC
V
REF
e a
2 5 V
DC
and f
CLK
e
4 MHz R
Source
e
50X unless otherwise
specified Boldface limits apply for T
A
e
T
J
e
T
MIN
to T
MAX
all other limits T
A
e
T
J
e
25 C
ADC08231
ADC08234 and
ADC08238 with BIN
Units
Symbol
Parameter
Conditions
CIN BIWM
(Limits)
CIWM or CIMF Suffixes
Typical
Limits
(Note 8)
(Note 9)
CONVERTER AND MULTIPLEXER CHARACTERISTICS
Linearity Error
V
REF
e a
2 5 V
DC
BIN BIWM
g
LSB (max)
CIN CIMF CIWM
g
1
LSB (max)
Gain Error
V
REF
e a
2 5 V
DC
BIN BIWM
g
1
LSB (max)
CIN CIMF CIWM
g
1
LSB (max)
Zero Error
V
REF
e a
2 5 V
DC
BIN BIWM
g
1
LSB (max)
CIN CIMF CIWM
g
1
LSB (max)
Total Unadjusted Error
V
REF
e a
5 V
DC
BIN BIWM
(Note 10)
g
1
LSB (max)
CIN CIMF CIWM
g
1
LSB (max)
Differential Linearity
V
REF
e a
2 5 V
DC
8
Bits (min)
R
REF
Reference Input Resistance
(Note 11)
3 5
kX
1 3
kX (min)
6 0
kX (max)
V
IN
Analog Input Voltage
(Note 12)
(V
CC
a
0 05)
V (max)
(GND
b
0 05)
V (min)
3
Electrical Characteristics
(Continued)
The following specifications apply for V
CC
e a
5 V
DC
V
REF
e a
2 5 V
DC
and f
CLK
e
4 MHz R
source
e
50X unless otherwise
specified Boldface limits apply for T
A
e
T
J
e
T
MIN
to T
MAX
all other limits T
A
e
T
J
e
25 C
ADC08231
ADC08234 and
ADC08238 with BIN
Units
Symbol
Parameter
Conditions
CIN BIWM
(Limits)
CIWM or CIMF Suffixes
Typical
Limits
(Note 8)
(Note 9)
CONVERTER AND MULTIPLEXER CHARACTERISTICS
(Continued)
DC Common-Mode Error
V
REF
e a
2 5 V
DC
g
LSB (max)
Power Supply Sensitivity
V
CC
e a
5V
g
5%
g
LSB (max)
V
REF
e a
2 5 V
DC
On Channel Leakage
On Channel
e
5V
0 2
m
A (max)
Current (Note 13)
Off Channel
e
0V
1
On Channel
e
0V
b
0 2
m
A (max)
Off Channel
e
5V
b
1
Off Channel Leakage
On Channel
e
5V
b
0 2
m
A (max)
Current (Note 13)
Off Channel
e
0V
b
1
On Channel
e
0V
0 2
m
A (max)
Off Channel
e
5V
1
DYNAMIC CHARACTERISTICS
(see Typical Converter Performance Characteristics)
S
N
a
D
Signal-to-
V
REF
e a
5V
(Noise
a
Distortion)
Sample Rate
e
286 kHz
Ratio
V
IN
e a
5 V
p-p
f
IN
e
10 kHz
48 35
dB
f
IN
e
50 kHz
48 00
dB
f
IN
e
100 kHz
47 40
dB
DIGITAL AND DC CHARACTERISTICS
V
IN(1)
Logical ``1'' Input Voltage
V
CC
e
5 25V
2 0
V (min)
V
IN(0)
Logical ``0'' Input Voltage
V
CC
e
4 75V
0 8
V (max)
I
IN(1)
Logical ``1'' Input Current
V
IN
e
5 0V
1
m
A (max)
I
IN(0)
Logical ``0'' Input Current
V
IN
e
0V
b
1
m
A (max)
V
OUT(1)
Logical ``1'' Output Voltage
V
CC
e
4 75V
I
OUT
e b
360 mA
2 4
V (min)
I
OUT
e b
10 mA
4 5
V (min)
V
OUT(0)
Logical ``0'' Output Voltage
V
CC
e
4 75V
0 4
V (max)
I
OUT
e
1 6 mA
I
OUT
TRI-STATE Output Current
V
OUT
e
0V
b
3 0
m
A (max)
V
OUT
e
5V
3 0
m
A (max)
I
SOURCE
Output Source Current
V
OUT
e
0V
b
6 5
mA (min)
I
SINK
Output Sink Current
V
OUT
e
V
CC
8 0
mA (min)
I
CC
Supply Current
CS
e
HIGH
ADC08234 ADC08238
3 0
mA (max)
ADC08231 (Note 16)
6 0
mA (max)
4
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