±1 5 k V ES D-P ro t e c t e d , S in g le /Du a l/Oc t a l,
CMOS S w it c h De b o u n c e rs
7/MAX618
meets Level 4 (the highest level) of IEC1000-4-2, with-
out the need for additional ESD-protection compo-
nents.
Machine Model
The Ma c hine Mod e l for ESD te s ts a ll p ins us ing a
200pF storage capacitor and zero discharge resis-
tance. Its objective is to emulate the stress caused by
contact that occurs with handling and assembly during
manufacturing.
The major difference between tests done using the
Human Body Model and IEC1000-4-2 is higher peak
current in IEC1000-4-2, because series resistance is
lower in the IEC1000-4-2 model. Hence, the ESD with-
stand voltage measured to IEC1000-4-2 is generally
lowe r tha n tha t me a s ure d us ing the Huma n Bod y
Model. Figure 7a shows the IEC1000-4-2 model and
Figure 7b shows the current waveform for the 8kV,
IEC1000-4-2, Level 4, ESD Contact-Discharge test.
MAX6 8 1 8 µP In t e rfa c in g
The MAX6818 has an output enable (EN) input that
allows switch outputs to be three-stated on the µP data
bus until polled by the µP. Also, state changes at the
switch inputs are detected, and an output (CH) goes low
after the debounce period to signal the µP. Figure 4
shows the timing diagram for enabling outputs and read-
ing data. If the output enable is not used, tie EN to GND
to “always enable’’ the switch outputs. If EN is low, CH is
always high. If a change of state is not required, leave
CH unconnected.
The Air-Gap test involves approaching the device with
a c ha rg e d p rob e . The Conta c t-Dis c ha rg e me thod
connects the probe to the device before the probe is
energized.
P in Co n fig u ra t io n s (c o n t in u e d )
TOP VIEW
EN
IN1
IN2
IN3
IN4
IN5
IN6
IN7
IN8
1
2
3
4
5
6
7
8
9
20 V
CC
19 OUT1
18 OUT2
17 OUT3
16 OUT4
15 OUT5
14 OUT6
13 OUT7
12 OUT8
11 CH
IN1
GND
IN2
1
2
3
6
5
4
OUT1
MAX6818
MAX6817
V
CC
OUT2
SOT23-6
GND 10
SSOP
___________________Ch ip In fo rm a t io n
MAX6816 TRANSISTOR COUNT: 284
MAX6817 TRANSISTOR COUNT: 497
MAX6818 TRANSISTOR COUNT: 2130
SUBSTRATE CONNECTED TO GND
_______________________________________________________________________________________
7
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
