Detailed Description

The MAX9030/MAX9031/MAX9032/MAX9034 are sin-

gle/dual/quad low-cost comparators. They have an

operating supply voltage from +2.5V to +5.5V when

operating from a single supply and from ±1.25V to

±2.75V when operating from dual power supplies, and

consume only 35µA. Their common-mode input voltage

range extends from the negative supply to within 1.1V

of the positive supply. Internal hysteresis ensures clean

output switching, even with slow-moving input signals.

Shutdown Mode

The MAX9030 comparator comes with a power-saving

shutdown mode. When in shutdown, the supply current

drops from a typical 35µA to 0.05µA, and the outputs

become high impedance. SHDN has a high input imped-

applied to SHDN places the device in the shutdown

applied to SHDN will enable normal operation. To dis-

Applications Information

Adding Hysteresis

Hysteresis extends the comparator’s noise margin by

increasing the upper threshold and decreasing the

lower threshold. A voltage-divider from the output of the

comparator sets the trip voltage. Therefore, the trip volt-

age is related to the output voltage.

These comparators have 4mV internal hysteresis.

Additional hysteresis can be generated with two resis-

tors using positive feedback (Figure 1). Use the follow-

ing procedure to calculate resistor values:

Low-Cost, Ultra-Small, Single/Dual/Quad

Single-Supply Comparators

6

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Pin Description

PIN

MAX9030

MAX9031

MAX9032

MAX9034

NAME

FUNCTION

11

——

IN+

Comparator Noninverting Input

224

11

Negative Supply Voltage. Bypass with a 0.1µF capacitor.

33

——

IN-

Comparator Inverting Input

44

——

OUT

Comparator Output

5

——

—

SHDN

Shutdown

658

4

Positive Supply Voltage. Bypass with a 0.1µF capacitor.

——

1

1

OUTA

Comparator A Output

——

2

2

INA-

Comparator A Inverting Input

——

3

3

INA+

Comparator A Noninverting Input

——

5

5

INB+

Comparator B Noninverting Input

——

6

6

INB-

Comparator B Inverting Input

——

7

7

OUTB

Comparator B Output

——

—

8

OUTC

Comparator C Output

——

—

9

INC-

Comparator C Inverting Input

——

—

10

INC+

Comparator C Noninverting Input

——

—

12

IND+

Comparator D Noninverting Input

——

—

13

IND-

Comparator D Inverting Input

——

—

14

OUTD

Comparator D Output