MAX9910 Maxim, MAX9910 Datasheet - Page 10

• Manufacturer Part Number: MAX9910
• Description: The single MAX9910/MAX9911 and dual MAX9912/MAX9913 operational amplifiers (op amps) feature a maximized ratio of gain bandwidth (GBW) to supply current and are ideal for battery-powered applications such as portable instrumentation, portable medical
• Manufacturer: Maxim

200kHz, 4µA, Rail-to-Rail
I/O Op Amps with Shutdown
rejection ratio of 95dB (typ) allows the devices to be
powered directly from a battery, simplifying design and
extending battery life.
The MAX9910–MAX9913 typically require 5µs after
power-up. Supply settling time depends on the supply
voltage, the value of the bypass capacitor, the output
impedance of the incoming supply, and any lead resis-
tance or inductance between components. Op-amp
settling time depends primarily on the output voltage
and is slew-rate limited. Figure 3 shows the MAX991_ in
a noninverting voltage follower configuration with the
input held at midsupply. The output settles in approxi-
mately 18µs for V
Characteristics for power-up settling time).
The MAX9911/MAX9913 feature active-low shutdown
inputs. The MAX9911/MAX9913 enter shutdown in 2µs
(typ) and exit in 30µs (typ). The amplifiers’ outputs are
in a high-impedance state in shutdown mode. Drive
SHDN low to enter shutdown. Drive SHDN high to
enable the amplifier. The MAX9913 dual-amplifier fea-
tures separate shutdown inputs. Shut down both ampli-
fiers for the lowest quiescent current.
To minimize noise, bypass V
to ground, as close to the pin as possible.
Good layout techniques optimize performance
by decreasing the amount of stray capacitance and
inductance to the op amps’ inputs and outputs.
Minimize stray capacitance and inductance by placing
external components close to the IC.
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Power-Supply Bypassing and Layout
DD
= 3V (see the Typical Operating
Power-Up Settling Time
DD
with a 0.1µF capacitor
Shutdown Mode
Figure 1. Rail-to-Rail Output Voltage Range
Figure 2. Using a Resistor to Isolate a Capacitive Load from
the Op Amp
Figure 3. Power-Up Test Configuration
0V
0V
3V
3V
0V
RAIL-TO-RAIL OUTPUT VOLTAGE RANGE
5.5V
MAX9910–
MAX9913
100kΩ
100kΩ
200µs/div
IN+
IN-
R
ISO
MAX991_
A
V
=
V
V
R
DD
SS
L
R
L
+ R
R
L
ISO
≈ 1V/V
IN_
OUT_
1V/div
1V/div
C
L
OUT