Mechanical Switch Monitor

The ability of the MAX1661/MAX1662/MAX1663 to read

back the logic state of the I/Os makes them suitable for

checking system status. They can be used as an

“open-lid indicator”, sensing a change in the I/O and

sending an interrupt to the master to indicate a change

in status (Figure 9). The same can be done to detect a

chassis intrusion.

Simple High-Voltage Switch

For applications requiring a higher voltage, use a sim-

ple resistive divider to protect the gate from breakdown

yet allow the MOSFETs to handle higher-voltage appli-

cations (Figure 10).

Serial-to-Parallel/Parallel-to-Serial Converters and

Load-Switch Controllers with SMBus Interface

______________________________________________________________________________________

13

MAX1661

MAX1662

MAX1663

I/O1

TO/FROM

HOST

+5V

I/O3

I/O2

GND

ALERT

0.1

µF

100k

100k

100k

SMBCLK

SMBDATA

SMBSUS

ADD

100

Ω*

*OPTIONAL

10k

10k

10k

Figure 9. Open-Lid Detect or Chassis Intrusion Detector

MAX1662

MAX1663

I/O1

TO/FROM

HOST

+5V

I/O3

I/O2

GND

LOAD

ALERT

0.1

µF

0.01

µF*

IRF7406

200k

SMBCLK

SMBDATA

SMBSUS

ADD

100

Ω*

*OPTIONAL

I/O2 AND I/O3 CAN BE CONFIGURED SIMILIARLY.

10k

10k

10k

200k

Figure 10. Simple High-Voltage Switch