Timing characteristics (figure 4) – Rainbow Electronics MAX126 User Manual
Page 5
MAX125/MAX126
2x4-Channel, Simultaneous-Sampling
14-Bit DAS
_______________________________________________________________________________________
5
CONDITIONS
ns
30
t
CW
CONVST Pulse Width
UNITS
MIN
TYP
MAX
SYMBOL
PARAMETER
TIMING CHARACTERISTICS
(Figure 4)
(AV
DD
= +5V, AV
SS
= -5V, DV
DD
= +5V, AGND = DGND = 0V, T
A
= T
MIN
to T
MAX
, unless otherwise noted.)
ns
0
t
CWS
CS to WR Setup Time
ns
0
t
CWH
CS to WR Hold Time
ns
30
t
WR
WR Low Pulse Width
ns
125
t
CSD
CS to CONVST Delay
ns
30
t
AS
Address Setup Time
ns
0
t
AH
Address Hold Time
25pF load
ns
30
t
ID
RD to INT Delay
ns
40
t
RD
Delay Time Between Reads
ns
0
t
CRS
CS to RD Setup Time
ns
0
t
CRH
CS to RD Hold Time
ns
30
t
RD
RD Low Pulse Width
25pF load (Note 13)
ns
30
t
DA
Data-Access Time
25pF load (Note 14)
ns
5
45
t
DH
Bus-Relinquish Time
Mode 1, 1 channel
µs
3
Mode 2, 2 channel
6
Mode 3, 3 channel
9
Mode 4, 4 channel
12
t
CONV
Exiting shutdown
µs
5
Start-Up Time
Note 1:
AV
DD
= +5V, AV
SS
= -5V, DV
DD
= +5V, V
REFIN
= 2.500V (external), V
IN
= ±5V (MAX125) or ±2.5V (MAX126).
Note 2:
Relative accuracy is the analog value’s deviation at any code from its theoretical value after the full-scale range has been
calibrated.
Note 3:
CLK synchronized with CONVST.
Note 4:
f
IN
= 10.06kHz, V
IN
= ±5V (MAX125) or ±2.5V (MAX126).
Note 5:
First five harmonics.
Note 6:
All inputs except CH1A driven with ±5V (MAX125) or ±2.5V (MAX126) 10kHz signal; CH1A connected to AGND and digitized.
Note 7:
Guaranteed by design. Not production tested.
Note 8:
AV
DD
= +5V, AV
SS
= -5V, DV
DD
= +5V, V
IN
= 0V (all channels).
Note 9:
Temperature drift is defined as the change in output voltage from +25°C to T
MIN
or T
MAX
. It is calculated as
TC = [
∆
REFOUT/REFOUT] /
∆
T.
Note 10:
See Figure 2.
Note 11:
Defined as the change in positive full scale caused by a ±5% variation in the nominal supply voltage. Tested with one input
at full scale and all others at AGND. V
REFIN
= 2.5V (internal).
Note 12:
Tested with V
IN
= AGND on all channels, V
REFIN
= 2.5V (internal).
Note 13:
The data-access time is defined as the time required for an output to cross 0.8V or 2.0V. It is measured using the circuit of
Figure 1. The measured number is then extrapolated back to determine the value with a 25pF load.
Note 14:
The bus-relinquish time is derived from the measured time taken for the data outputs to change 0.5V when loaded with the
circuit of Figure 1. The measured number is then extrapolated back to remove the effects of charging/discharging the 120pF
capacitor. Thus, the time given is the part’s true bus-relinquish time, independent of the external bus loading capacitance.
Conversion Time
Mode 1, 1 channel
ksps
250
Conversion Rate/Channel
Mode 2, 2 channel
142
Mode 3, 3 channel
100
Mode 4, 4 channel
76