Datasheet

5
LTC1290
1290fe
LTC1290B/LTC1290C/LTC1290D
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
IH
High Level Input Voltage V
CC
= 5.25V ● 2.0 V
V
IL
Low Level Input Voltage V
CC
= 4.75V ● 0.8 V
I
IH
High Level Input Current V
IN
= V
CC
● 2.5 µA
I
IL
Low Level Input Current V
IN
= 0V ● –2.5 µA
V
OH
High Level Output Voltage V
CC
= 4.75V I
O
= 10µA 4.7 V
I
O
= 360µA ● 2.4 4.0 V
V
OL
Low Level Output Voltage V
CC
= 4.75V I
O
= 1.6mA ● 0.4 V
I
OZ
High-Z Output Leakage V
OUT
= V
CC
, CS High ● 3 µA
V
OUT
= 0V, CS High ● –3 µA
I
SOURCE
Output Source Current V
OUT
= 0V –20 mA
I
SINK
Output Sink Current V
OUT
= V
CC
20 mA
I
CC
Positive Supply Current CS High ● 612 mA
CS High LTC1290BC, LTC1290CC ● 510 µA
Power Shutdown LTC1290DC, LTC1290BI
ACLK Off LTC1290CI, LTC1290DI
LTC1290BM, LTC1290CM ● 515 µA
LTC1290DM
(OBSOLETE)
I
REF
Reference Current V
REF
= 5V ● 10 50 µA
I
–
Negative Supply Current CS High ● 150 µA
V
CC
levels (4.5V), as high level reference or analog inputs (5V) can cause
this input diode to conduct, especially at elevated temperatures and cause
errors for inputs near full scale. This spec allows 50mV forward bias of
either diode. This means that as long as the reference or analog input does
not exceed the supply voltage by more than 50mV, the output code will be
correct. To achieve an absolute 0V to 5V input voltage range will therefore
require a minimum supply voltage of 4.950V over initial tolerance,
temperature variations and loading.
Note 8: Channel leakage current is measured after the channel selection.
Note 9: To minimize errors caused by noise at the chip select input, the
internal circuitry waits for two ACLK falling edge after a chip select falling
edge is detected before responding to control input signals. Therefore, no
attempt should be made to clock an address in or data out until the
minimum chip select setup time has elapsed.
Note 10: Increased leakage currents at elevated temperatures cause the
S/H to droop, therefore it's recommended that f
ACLK
≥ 125kHz at 85°C and
f
ACLK
≥ 15kHz at 25°C.
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: All voltage values are with respect to ground with DGND, AGND
and REF
–
wired together (unless otherwise noted).
Note 3: V
CC
= 5V, V
REF
+
= 5V, V
REF
–
= 0V, V
–
= 0V for unipolar mode and
–5V for bipolar mode, ACLK = 4.0MHz unless otherwise specified.
Note 4: These specs apply for both unipolar and bipolar modes. In bipolar
mode, one LSB is equal to the bipolar input span (2V
REF
) divided by 4096.
For example, when V
REF
= 5V, 1LSB (bipolar) = 2(5V)/4096 = 2.44mV.
Note 5: Integral nonlinearity is defined as the deviation of a code from a
straight line passing through the actual endpoints of the transfer curve.
The deviation is measured from the center of the quantization band.
Note 6: Recommended operating conditions.
Note 7: Two on-chip diodes are tied to each reference and analog input
which will conduct for reference or analog input voltages one diode drop
below V
–
or one diode drop above V
CC
. Be careful during testing at low
E
LECTR
IC
AL C CHARA TER ST
ICS
DIGITAL
A
D
U
I
DC
The ● denotes the specifications which
apply over the full operating temperature range, otherwise specifications are at T
A
= 25°C. (Note 3)