ISL28166_08 Datasheet, PDF (9/13 Pages) Intersil Corporation – 39μA Micropower Single and Dual Rail-to-Rail Input-Output Low Input Bias Current (RRIO) Op Amps

Pin Descriptions
ISL28166
(6 Ld SOT-23)
ISL28266
(8 Ld SOIC)
(8 Ld MSOP)
4
2 (A)
6 (B)
3
3 (A)
5 (B)
2
4
1
1 (A)
7 (B)
ISL28166, ISL28266
PIN NAME
IN-
IN-_A
IN-_B
IN+
IN+_A
IN+_B
V-
OUT
OUT_A
OUT_B
FUNCTION
Inverting input
EQUIVALENT CIRCUIT
V+
IN-
IN+
Non-inverting input (See Circuit 1)
V-
Circuit 1
Negative supply
Output
V+
OUT
6
8
V+
Positive supply
5
ENABLE
Chip enable
V-
Circuit 2
V+
CE
Applications Information
Introduction
The ISL28166 is a single BiMOS rail-to-rail input, output
(RRIO) operational amplifier with an enable feature. The
ISL28266 is a dual version without the enable feature. Both
devices are designed to operate from single supply (2.4V to
5.0V) or dual supplies (±1.2V to ±2.5V) while drawing only
39µA of supply current per amplifier. This combination of low
power and precision performance makes this device suitable
for a variety of low power applications including battery
powered systems.
Rail-to-Rail Input/Output
These devices feature bi-polar inputs which have an input
common mode range that extends to the rails, and CMOS
outputs that can typically swing to within about 4mV of the
supply rails with a 100kΩ load. The NMOS sinks current to
swing the output in the negative direction. The PMOS sources
current to swing the output in the positive direction.
Input Protection
All input terminals have internal ESD protection diodes to both
positive and negative supply rails, limiting the input voltage to
V-
Circuit 3
within one diode beyond the supply rails. They also contain
back-to-back diodes across the input terminals. For
applications where the input differential voltage is expected to
exceed 0.5V, external series resistors must be used to ensure
the input currents never exceed 5mA (Figure 35).
-
R_IN
V_IN
+
R_L
V_OUT
FIGURE 35. INPUT CURRENT LIMITING
Enable/Disable Feature
The ISL28166 offers an EN pin that disables the device
when pulled up to at least 2.0V. In the disabled state (output
in a high impedance state), the part consumes typically
10µA. By disabling the part, multiple ISL28166 parts can be
connected together as a MUX. In this configuration, the
outputs are tied together in parallel and a channel can be
selected by the EN pin. The EN pin also has an internal
pull-down. If left open, the EN pin will pull to the negative rail
and the device will be enabled by default.
9
FN6155.3
March 20, 2008