ADS-238Q
器件资料摘要：
Figure 1. ADS-238Q Functional Block Diagram
FEATURES
G183 20MHz sampling rate
G183 Low Power, 100mW, max
G183 100MHz full power input bandwidth
G183 Integral sample-and-hold
G183 Single +3V supply operation
G183 TTL compatible digital output
G183 Offset binary output coding
GENERAL DESCRIPTION
The ADS-238Q is a monolithic, 12-bit, 20MHz, sampling
analog-to-digital converter fabricated in a CMOS process.
The converter is designed for applications where high speed,
wide bandwidth and low power dissipation are essential.
These characteristics are provided through the use of a fully
differential pipeline A/D architecture with digital error
correction logic for the eleven most significant bits.
The ADS-238Q offers excellent dynamic performance while
consuming only 79mW, typical. The power dissipation is
approximately proportional to the sampling rate, thus the
ADS-238Q is ideal for low power applications between 1 and
20 MHz. With low distortion and high dynamic range, this
device provides the performance required for imaging,
telecommunications, multimedia, and instrumentation
applications.
The ADS-238Q is available in a 44-pin (plastic) TQFP
package and operates over the commercial 0°C to 70°C
temperature range.
C174 C174
C73C78C78C79C86C32C65C32C84C73C79C78C32C97C110C100C32C69C88C32C67C69C76C76C69C78C67C69
INPUT/OUTPUT CONNECTIONS
PIN FUNCTION PIN FUNCTION
1 GND 44 VS
2 CLK 43 BIT 12 (LSB)
3N.C. 42BIT 11
4VS 41 BIT 10
5VS 40 BIT 9
6VS 39 BIT 8
7VS 38 BIT 7
8VS 37 BIT 6
9VS 36 BIT 5
10 VREF– 35 BIT 4
11 VREF+ 34 BIT 3
12 N.C. 33 BIT 2
13 N.C. 32 BIT 1
14 N.C. 31 GND
15 GND 30 GND
16 BIAS1 29 GND
17 BIAS2 28 GND
18 VCM 27 GND
19 GND 26 GND
20 VIN+ 25 GND
21 VIN– 24 GND
22 GND 23 GND
ADS-238Q
12-Bit, 20MHz, Low Power
Sampling A/D Converters
DATEL, Inc., 11 Cabot Boulevard, Mansfield, MA 02048 (U.S.A.) G183 Tel: (508)339-3000 Fax: (508)339-6356 G183 For immediate assistance: (800) 233-2765
Note: Recommend that N.C. (no connect) pins be connected to analog ground.
X2
+
–
+
–
2 CLK
X2
S/H
å
Bias
Current
Adjust
2-Bit
Flash A/D
2-Bit
Flash A/D
2-Bit
Flash A/D
Stage 10
4 to 9, 44
+VS
1, 15, 19, 22 to 31
GND
Stage 1
Reference
Input
Common Mode
Voltage Reference
VREF+
BIAS2
BIAS1
VREF–
VIN+
VIN–
VCM
11
16
17
10
20
21
18
Clock
2-Bit
DAC
2-Bit
DAC
Digital Delay
and Error
Correction
32
33
34
35
36
37
38
39
40
41
42
43
Bit 1 (MSB)
Bit 2
Bit 3
Bit 4
Bit 5
Bit 6
Bit 7
Bit 8
Bit 9
Bit 10
Bit 11
Bit 12 (LSB)
å
FEATURES
G183 20MHz sampling rate
G183 Low Power, 100mW, max
G183 100MHz full power input bandwidth
G183 Integral sample-and-hold
G183 Single +3V supply operation
G183 TTL compatible digital output
G183 Offset binary output coding
GENERAL DESCRIPTION
The ADS-238Q is a monolithic, 12-bit, 20MHz, sampling
analog-to-digital converter fabricated in a CMOS process.
The converter is designed for applications where high speed,
wide bandwidth and low power dissipation are essential.
These characteristics are provided through the use of a fully
differential pipeline A/D architecture with digital error
correction logic for the eleven most significant bits.
The ADS-238Q offers excellent dynamic performance while
consuming only 79mW, typical. The power dissipation is
approximately proportional to the sampling rate, thus the
ADS-238Q is ideal for low power applications between 1 and
20 MHz. With low distortion and high dynamic range, this
device provides the performance required for imaging,
telecommunications, multimedia, and instrumentation
applications.
The ADS-238Q is available in a 44-pin (plastic) TQFP
package and operates over the commercial 0°C to 70°C
temperature range.
C174 C174
C73C78C78C79C86C32C65C32C84C73C79C78C32C97C110C100C32C69C88C32C67C69C76C76C69C78C67C69
INPUT/OUTPUT CONNECTIONS
PIN FUNCTION PIN FUNCTION
1 GND 44 VS
2 CLK 43 BIT 12 (LSB)
3N.C. 42BIT 11
4VS 41 BIT 10
5VS 40 BIT 9
6VS 39 BIT 8
7VS 38 BIT 7
8VS 37 BIT 6
9VS 36 BIT 5
10 VREF– 35 BIT 4
11 VREF+ 34 BIT 3
12 N.C. 33 BIT 2
13 N.C. 32 BIT 1
14 N.C. 31 GND
15 GND 30 GND
16 BIAS1 29 GND
17 BIAS2 28 GND
18 VCM 27 GND
19 GND 26 GND
20 VIN+ 25 GND
21 VIN– 24 GND
22 GND 23 GND
ADS-238Q
12-Bit, 20MHz, Low Power
Sampling A/D Converters
DATEL, Inc., 11 Cabot Boulevard, Mansfield, MA 02048 (U.S.A.) G183 Tel: (508)339-3000 Fax: (508)339-6356 G183 For immediate assistance: (800) 233-2765
Note: Recommend that N.C. (no connect) pins be connected to analog ground.
X2
+
–
+
–
2 CLK
X2
S/H
å
Bias
Current
Adjust
2-Bit
Flash A/D
2-Bit
Flash A/D
2-Bit
Flash A/D
Stage 10
4 to 9, 44
+VS
1, 15, 19, 22 to 31
GND
Stage 1
Reference
Input
Common Mode
Voltage Reference
VREF+
BIAS2
BIAS1
VREF–
VIN+
VIN–
VCM
11
16
17
10
20
21
18
Clock
2-Bit
DAC
2-Bit
DAC
Digital Delay
and Error
Correction
32
33
34
35
36
37
38
39
40
41
42
43
Bit 1 (MSB)
Bit 2
Bit 3
Bit 4
Bit 5
Bit 6
Bit 7
Bit 8
Bit 9
Bit 10
Bit 11
Bit 12 (LSB)
å