ISL28271_07 Datasheet, PDF (10/14 Pages) Intersil Corporation – Dual Micropower, Single Supply, Rail-to- Rail Input and Output (RRIO) Instrumentation Amplifier

ISL28271, ISL28272
Pin Descriptions
ISL28271
ISL28272
16 Ld QSOP 16 Ld QSOP
2, 15
2, 15
PIN NAME
OUT_A,
OUT_B
3, 14
3, 14
FB+_A,
FB+_B
4, 13
4, 13
FB-_A,
FB-_B
5, 12
5, 12
IN-_A,
IN-_B
6, 11
6, 11
IN+_A,
IN+_B
7, 10
16
8
1, 9
7, 10
16
8
1, 9
EN_A,
EN_B
V+
V-
NC
EQUIVALENT
CIRCUIT
PIN FUNCTION
Circuit 3
Output Voltage. A complementary Class AB common-source output stage drives
the output of each channel. When disabled, the outputs are in a high impedance
state.
Circuit 1A,
Circuit 1B
Positive Feedback high impedance terminals. ISL28272 input circuit is shown in
Circuit 1A, and the ISL28271 input circuit is shown in Circuit 1B.
ISL28271: to avoid offset drift, it is recommended that the terminals of the
ISL28271 are not overdriven beyond 1V and the input current must never
exceed 5mA.
Circuit 1A,
Circuit 1B
Negative Feedback high impedance terminals. The FB- pins connect to an
external resistor divider to individually set the desired gain of the in-amp.
ISL28272 input circuit is shown in Circuit 1A, and the ISL28271 input circuit is
shown in Circuit 1B.
ISL28271: to avoid offset drift, it is recommended that the terminals of the
ISL28271 are not overdriven beyond 1V and the input current must never
exceed 5mA.
Circuit 1A,
Circuit 1B
High impedance Inverting input terminals. Connect to the low side of the input
source signal. ISL28272 input circuit is shown in Circuit 1A, and the ISL28271
input circuit is shown in Circuit 1B.
ISL28271: to avoid offset drift, it is recommended that the terminals of the
ISL28271 are not overdriven beyond 1V and the input current must never
exceed 5mA.
Circuit 1A,
Circuit 1B
High impedance Non-inverting input terminals. Connect to the high side of the
input source signal. ISL28272 input circuit is shown in Circuit 1A, and the
ISL28271 input circuit is shown in Circuit 1B.
ISL28271: to avoid offset drift, it is recommended that the terminals of the
ISL28271 are not overdriven beyond 1V and the input current must never
exceed 5mA.
Circuit 2
Active LOW logic pins. When pulled above 2V, the corresponding channel turns
off and OUT is high impedance. A channel is enabled when pulled below 0.8V.
Built-in pull downs define each EN pin LOW when left floating.
Circuit 4 Positive Supply terminal shared by all channels.
Circuit 4
Negative Supply terminal shared by all channels. Grounded for single supply
operation.
No Connect, pins can be left floating or grounded.
IN-
FB-
CIRCUIT 1A
IN-
FB-
V₊
IN+
FB+
V_-
LOGIC
PIN
V₊
IN+
FB+
V_-
V₊
V_-
CIRCUIT 2
V₊
OUT
V_-
CIRCUIT 3
V₊
CAPACITIVELY
COUPLED
ESD CLAMP
V_-
CIRCUIT 4
CIRCUIT 1B
10
FN6390.2
August 17, 2007