Single/Dual/Quad, Wide-Bandwidth, Low-Power,

Single-Supply, Rail-to-Rail I/O Op Amps

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11

Power-Up and Shutdown Mode

The MAX4130–MAX4134 amplifiers typically settle with-

in 1µs after power-up. Figures 9 and 10 show the out-

put voltage and supply current on power-up, using the

test circuit of Figure 8.

The MAX4131 and MAX4133 have a shutdown option.

When the shutdown pin (SHDN) is pulled low, the sup-

ply current drops below 25µA per amplifier and the

amplifiers are disabled with the outputs in a high-

impedance state. Pulling SHDN high or leaving it float-

ing enables the amplifier. In the dual-amplifier

MAX4133, the shutdown functions operate indepen-

dently. Figures 11 and 12 show the output voltage and

supply current responses of the MAX4131 to a shut-

down pulse, using the test circuit of Figure 8.

Figure 7. Capacitive-Load Driving Circuit

SHDN

OUT

0V TO 2.7V

STEP FOR

SHUTDOWN

TEST

0V TO 2.7V STEP

FOR POWER-UP

TEST; 2.7V FOR

SHUTDOWN

ENABLE TEST.

SUPPLY-CURRENT

MONITORING POINT

µF

10

Ω

2k

*FOR SHUTDOWN TEST ONLY.

10k

2k

Figure 8. Power-Up/Shutdown Test Circuit

TIME (5

µs/div)

OUT

Figure 9. Power-Up Output Voltage

(1V/div)

TIME (5

µs/div)

(500

µA/div)

Figure 10. Power-Up Supply Current