AD1555 Analog Devices, AD1555 Datasheet - Page 5

• Manufacturer Part Number: AD1555
• Description: 24-Bit, 121 dB typical SNR, Sigma-Delta A/D converter with Integrated PGA
• Manufacturer: Analog Devices

Specifications of AD1555

• Resolution (bits): 24bit
• # Chan: 2
• Sample Rate: 256kSPS
• Interface: Byte,Ser
• Analog Input Type: Diff-Bip,SE-Bip
• Ain Range: Bip 2.25V/(PGA Gain)
• Adc Architecture: Sigma-Delta Modulator
• Pkg Type: LCC

TIMING SPECIFICATIONS
CLKIN Frequency
CLKIN Duty Cycle Error
MCLK Output Frequency
SYNC Setup Time
SYNC Hold Time
CLKIN Rising to MCLK Output Falling on SYNC
CLKIN Falling to MCLK Output Rising
CLKIN Falling to MCLK Output Falling
MCLK Input Falling to MDATA Falling
MCLK Input Rising to MDATA and MFLG Valid
TDATA Setup Time after SYNC
TDATA Hold Time
RESET Setup Time
RESET Hold Time
CLKIN Falling to DRDY Rising
CLKIN Rising to DRDY Falling
CLKIN Rising to ERROR Falling
RSEL to Data Valid
RSEL Setup to SCLK Falling
DRDY to Data Valid
DRDY High Setup to SCLK Falling
R/W to Data Valid
R/W High Setup to SCLK Falling
CS to Data Valid
CS Low Setup to SCLK Falling
SCLK Rising to DOUT Valid
SCLK High Pulsewidth
SCLK Low Pulsewidth
SCLK Period
SCLK Falling to DRDY Falling
CS High or R/W Low to DOUT Hi-Z
R/W Low Setup to SCLK Falling
CS Low Setup to SCLK Falling
Data Setup Time to SCLK Falling
Data Hold Time after SCLK Falling
R/W Hold Time after SCLK Falling
NOTES
1
2
Specifications subject to change without notice.
REV. B
The gain of the modulator is proportional to f
With DRDYBUF low only. When DRDYBUF is high, this timing also depends on the value of the external pull-down resistor.
1
1
2
2
CLKIN
(+V
CLKIN = 1.024 MHz; AGND = DGND = 0 V; C
Figure 2. Load Circuit for Digital Interface Timing
and MCLK frequency.
A
= +5 V
TO OUTPUT
PIN
5%; –V
50pF
C
L
A
= –5 V
Symbol
f
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
CLKIN
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
–5–
500 A
1.6mA
5%; AD1555 V
I
I
OH
OL
L
= 50 pF; T
Min
0.975
45
10
10
5
5
15
15
10
10
10
10
25
25
70
10
10
10
10
10
1.4V
L
= 5 V
A
= T
5%, AD1556 V
MIN
Typ
1.024
f
CLKIN
to T
MAX
/4
, unless otherwise noted)
L
AD1555/AD1556
= 2.85 V to 5.25 V;
Max
1.075
55
20
20
20
30
100
20
20
50
25
25
25
25
25
20
20
Unit
MHz
%
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns