MAX1497 Datasheet, PDF (29/33 Pages) Maxim Integrated Products – 3.5- and 4.5-Digit, Single-Chip ADCs with LED Drivers and μC Interface

3.5- and 4.5-Digit, Single-Chip ADCs with LED
Drivers and µC Interface
Definitions
INL
Integral nonlinearity (INL) is the deviation of the values on
an actual transfer function from a straight line. This straight
line is either a best-straight-line fit or a line drawn between
the end points of the transfer function, once offset and
gain errors have been nullified. INL for the MAX1497/
MAX1499 is measured using the endpoint method.
DNL
Differential nonlinearity (DNL) is the difference between
an actual step width and the ideal value of ±1 LSB. A
DNL error specification of less than ±1 LSB guarantees
no missing codes and a monotonic transfer function.
Rollover Error
Rollover error is defined as the absolute-value differ-
ence between a near positive full-scale reading and
near negative full-scale reading. Rollover error is tested
by applying a full-scale positive voltage, swapping
AIN+ and AIN-, and adding the results.
Zero Input Reading
Ideally, with AIN+ connected to AIN-, the MAX1497/
MAX1499 digital ADC result is 0000h. Zero input read-
ing is the measured deviation from the ideal 0x0000
and the actual measured point.
Gain Error
Gain error is the amount of deviation between the mea-
sured full-scale transition point and the ideal full-scale
transition point.
Common-Mode Rejection
Common-mode rejection (CMR) is the ability of a
device to reject a signal that is common to both input
terminals. The common-mode signal can be either an
AC or a DC signal or a combination of the two. CMR is
often expressed in decibels.
Normal-Mode 50Hz and 60Hz Rejection
(Simultaneously)
Normal-mode rejection is a measure of how much output
changes when a 50Hz and a 60Hz signal is injected into
only one of the differential inputs. The MAX1497/
MAX1499 sigma-delta converter uses its internal digital
filter to provide normal-mode rejection to both 50Hz and
60Hz power-line frequencies simultaneously.
Power-Supply Rejection Ratio
Power-supply rejection ratio (PSRR) is the ratio of the input
supply change (in volts) to the change in the converter
output (in volts). It is typically measured in decibels.
Pin Configurations
TOP VIEW
TOP VIEW
VNEG 1
REF- 2
REF+ 3
AIN+ 4
AIN- 5
I_SET 6
GND 7
V_DD 8
CLK 9
EOC 10
CS 11
DIN 12
SCLK 13
DOUT 14
MAX1497
28 SEGDP
27 SEGG
26 SEGF
25 VLED
24 SEGE
23 SEGD
22 SEGC
21 SEGB
20 SEGA
19 DIG3
18 DIG2
17 GLED
16 DIG1
15 DIG0
SSOP/PDIP
REF+ 1
AIN+ 2
AIN- 3
I_SET 4
GND 5
AV_DD 6
DV_DD 7
CLK 8
32 31 30 29 28 27 26 25
MAX1499
24 SEGE
23 SEGD
22 SEGC
21 SEGB
20 SEGA
19 DIG4
18 DIG3
17 DIG2
9 10 11 12 13 14 15 16
TQFP
Chip Information
TRANSISTOR COUNT: 80,000
PROCESS: BiCMOS
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