Datasheet

9
Maxim Integrated
MAX985/MAX986/MAX989/
MAX990/MAX993/MAX994
Micropower, Low-Voltage, UCSP/SC70,
Rail-to-Rail I/O Comparators
Zero-Crossing Detector
Figure 3 shows a zero-crossing detector application.
The MAX985’s inverting input is connected to ground,
and its noninverting input is connected to a 100mV
P-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 MAX986 is powered by the 5V
supply voltage, and the pullup resistor for the MAX986’s
open-drain output is connected to the 3V supply voltage.
This configuration allows the full 5V logic swing without
creating overvoltage on the 3V logic inputs. For 3V to 5V
logic-level translation, simply connect the 3V supply to
V
CC
and the 5V supply to the pullup resistor.
MAX985
IN+
3
4
OUT
1
2
5
V
CC
100mV
V
CC
V
EE
IN-
MAX986
IN-
100kΩ
100kΩ
4
3
R
PULLUP
3V (5V)
LOGIC OUT
OUT
1
5
2
V
CC
5V (3V)
3V (5V)
V
EE
5V (3V) LOGIC IN
IN+
Figure 3. Zero-Crossing Detector Figure 4. Logic-Level Translator