MAX13037/MAX13038
Automotive Contact Monitor and
Level Shifters with LDO Regulator
_______________________________________________________________________________________ 9
Pin Description
PIN NAME FUNCTION
1, 15, 31 GND Ground
2 IN0
Switch Input Channel 0. Connect IN0 to a switch connected to GND. IN0 can be programmed as a
direct input with a level-shifted output on DO0 (see the Mechanical Switch Inputs (IN0–IN7) section).
3 IN1
Switch Input Channel 1. Connect IN1 to a switch connected to GND. IN1 can be programmed as a
direct input with a level-shifted output on DO1 (see the Mechanical Switch Inputs (IN0–IN7) section).
4 IN2 Switch Input Channel 2. Connect IN2 to a switch connected to GND.
5 IN3 Switch Input Channel 3. Connect IN3 to a switch connected to GND.
6 IN4 Switch Input Channel 4. Connect IN4 to a switch connected to GND or BAT.
7 IN5 Switch Input Channel 5. Connect IN5 to a switch connected to GND or BAT.
8 IN6 Switch Input Channel 6. Connect IN6 to a switch connected to GND or BAT.
9 IN7 Switch Input Channel 7. Connect IN7 to a switch connected to GND or BAT.
10, 11, 34 N.C. No Connection. Not internally connected.
12 HYST
Hysteresis Input. Connect HYST to GND with a 0Ω to 900kΩ resistor to set the input voltage
hysteresis on IN0–IN7.
13 WET
Wetting Current Input. Connect a 30kΩ to 330kΩ resistor from WET to GND to set the wetting current
on IN0–IN7.
14 TDEB
Switch Debounce Time Input. Connect a 500pF to 10nF capacitor from TDEB to GND to set the
switch debounce time.
16 OT
Overtemperature Warning Output. OT is an open-drain output that asserts low when the thermal
warning threshold is exceeded.
17 INT
Interrupt Output. INT is an open-drain output that asserts low when one or more of the IN0–IN7 inputs
change state and are enabled for interrupts or when the watchdog times out.
18 TD
Reset and Watchdog Timeout Input. Connect TD to GND with a 500pF to 10nF capacitor to set the
timeout period for the reset and watchdog.
V
LO
TRANSIENT LOAD REGULATION
MAX13037/8toc18
1ms/div
I
LO
50mA/div
V
LO
(AC-COUPLED)
50mV/div
Typical Operating Characteristics (continued)
(BAT = +14V, SD = V
BAT
, R
WET
= 61kΩ, R
HYST
= 90kΩ, C
TDEB
= 4700pF, C
TD
= 4700pF, T
A
= +25°C, unless otherwise noted.)
WATCHDOG INTERRUPT AND RESET
PERIOD vs. TEMPERATURE
MAX13037/8toc19
TEMPERATURE (
°
C)
PERIOD (ms)
50
90
70
80
60
100
-40 125-10-25 5 20 35 65 11050 80 95
WATCHDOG INTERRUPT AND RESET
PERIOD vs. C
TD
MAX13037/8toc20
C
TD
(pF)
PERIOD (ms)
0
100
125
50
75
25
150
0 10,0002000 80004000 6000
