High-Speed, Micropower, Low-Voltage,

SOT23, Rail-to-Rail I/O Comparators

10

______________________________________________________________________________________

Zero-Crossing Detector

Figure 3 shows a zero-crossing detector application.

The MAX987’s inverting input is connected to ground,

and its noninverting input is connected to a 100mVp-p

signal source. As the signal at the noninverting input

crosses 0V, the comparator’s output changes state.

Logic-Level Translator

Figure 4 shows an application that converts 5V logic lev-

els to 3V logic levels. The MAX988 is powered by the +5V

supply voltage, and the pullup resistor for the MAX988’s

open-drain output is connected to the +3V supply volt-

age. This configuration allows the full 5V logic swing with-

out creating overvoltage on the 3V logic inputs. For 3V to

5V logic-level translation, simply connect the +3V supply

MAX987

IN+

4

3

OUT

1

2

5

100mV

IN-

0.1µF

MAX988

IN-

100kΩ

100kΩ

4

3

3V (5V)

LOGIC OUT

OUT

1

5

2

+5V (+3V)

+3V (+5V)

5V (3V) LOGIC IN

IN+

0.1µF

Figure 3. Zero-Crossing Detector

Figure 4. Logic-Level Translator

Pin Configurations (continued)

14

13

12

11

10

9

8

1

2

3

4

5

6

7

OUTD

IND-

IND+

INA+

INA-

OUTA

MAX995

MAX996

INC+

INC-

OUTC

OUTB

INB-

INB+

SO/TSSOP

OUT

N.C.

1

2

8

7

N.C.

IN-

IN+

N.C.

SO

TOP VIEW

3

4

6

5

MAX987

MAX988

INB-

INB+

1

2

8

7

OUTB

INA-

INA+

OUTA

SO/µMAX/SOT23

3

4

6

5

MAX991

MAX992