LTC1290BIJ Linear Technology, LTC1290BIJ Datasheet - Page 25

• Manufacturer Part Number: LTC1290BIJ
• Description: 12-BIT SERIAL I/O ADC W/8 CH MUX
• Manufacturer: Linear Technology
• Type: Data Acquisition System (DAS), ADCr

Specifications of LTC1290BIJ

• Resolution (bits): 12 b
• Sampling Rate (per Second): 50k
• Data Interface: Serial, Parallel
• Voltage Supply Source: Dual ±
• Voltage - Supply: ±5V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Through Hole
• Package / Case: *
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

How the various power supplies to the LTC1290 are
applied can also lead to overvoltage conditions. For single
supply operation (i.e., unipolar mode), if V
not tied together, then V
REF
from REF
A
PPLICATI
+
. If this sequence cannot be met, connecting a diode
V
IN
+
Figure 20. Overvoltage Protection for MUX
to V
1k
CC
O
LTC1290
is recommended (see Figure 21).
U
CH0
DGND
S
REF
LTC1290
V
CC
CC
Figure 21
+
I FOR ATIO
should be turned on first, then
U
20
14
AGND
V
V
CC
–
1N4148
W
22µF
5V
22µF
CC
1290 F21
5V
V
REF
0.1µF
1290 F20
and REF
–5V
U
+
are
For dual supplies (bipolar mode) placing two Schottky
diodes from V
power supply reversal from occurring when an input
source is applied to the analog MUX before power is
applied to the device. Power supply reversal occurs, for
example, if the input is pulled below V
a diode drop below ground which could cause the device
not to power up properly. Likewise, if the input is pulled
above V
ground. If no inputs are present on the MUX, the Schottky
diodes are not required if V
Because a unique input protection structure is used on the
digital input pins, the signal levels on these pins can
exceed the device V
CC
then V
Figure 22. Power Supply Reversal
DGND
CC
LTC1290
and V
–
CC
AGND
will be pulled a diode drop above
V
V
–
CC
without damaging the device.
–
to ground (Figure 23) will prevent
–
is applied first, then V
1N5817
1N5817
–
then V
LTC1290
22µF
0.1µF
1290 F22
5V
CC
–5V
will pull
25
CC
1290fe
.