19-1902; Rev 1; 8/94
Hig h -Vo lt a g e , Fa u lt -P ro t e c t e d
An a lo g Mu lt ip le x e rs
8/MAX379
_______________Ge n e ra l De s c rip t io n
____________________________Fe a t u re s
♦ Fault Input Voltage ±75V with Power Supplies Off
♦ Fault Input Voltage ±60V with ±15V Power Supplies
♦ All Switches Off with Power Supplies Off
The MAX378 8-channel single-ended (1-of-8) multiplexer
and the MAX379 4-channel differential (2-of-8) multiplexer
use a series N-channel/P-channel/N-channel structure to
provide significant fault protection. If the power supplies to
the MAX378/MAX379 are inadvertently turned off while
input voltages are still applied, all channels in the muxes
are turned off, and only a few nanoamperes of leakage cur-
rent will flow into the inputs. This protects not only the
MAX378/MAX379 and the circuitry they drive, but also the
sensors or signal sources that drive the muxes.
♦ On Channel Turns OFF if Overvoltage Occurs on
Input or Output
♦ Only Nanoamperes of Input Current Under All
Fault Conditions
♦ No Increase in Supply Currents Due to Fault
Conditions
♦ Latchup-Proof Construction
The series N-channel/P-channel/N-channel protection
structure has two significant advantages over the simple
current-limiting protection scheme of the industry’s first-
generation fault-protected muxes. First, the Maxim protec-
tion scheme limits fault currents to nanoamp leakage
values rather than many milliamperes. This prevents dam-
age to sensors or other sensitive signal sources. Second,
the MAX378/MAX379 fault-protected muxes can withstand
a continuous ±60V input, unlike the first generation, which
had a continuous ±35V input limitation imposed by power
dissipation considerations.
♦ Operates from ±4.5V to ±18V Supplies
♦ All Digital Inputs are TTL and CMOS Compatible
♦ Low-Power Monolithic CMOS Design
______________Ord e rin g In fo rm a t io n
PART
TEMP. RANGE
0°C to +70°C
PIN-PACKAGE
16 Plastic DIP
24 Wide SO
16 CERDIP
Dice**
MAX378CPE
MAX378CWG
MAX378CJE
MAX378C/D
MAX378EPE
MAX378EWG
MAX378EJE
MAX378MJE
MAX378MLP
0°C to +70°C
All digital inputs have logic thresholds of 0.8V and 2.4V,
ensuring both TTL and CMOS compatibility without requir-
ing pull-up resistors. Break-before-make operation is
guaranteed. Power dissipation is less than 2mW.
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-55°C to +125°C
-55°C to +125°C
16 Plastic DIP
24 Wide SO
16 CERDIP
16 CERDIP
20 LCC*
________________________Ap p lic a t io n s
Data Acquisition Systems
Industrial and Process Control Systems
Avionics Test Equipment
Ordering Information continued at end of data sheet.
* Contact factory for availability.
**The substrate may be allowed to float or be tied to V+ (JI CMOS).
Signal Routing Between Systems
__________________________________________________________P in Co n fig u ra t io n s
TOP VIEW
A0
EN
V-
1
2
3
4
5
6
7
8
A0
EN
1
2
3
4
5
6
7
8
A1
A1
16
16
15 A2
15 GND
14 V+
V-
14 GND
13 V+
IN1
IN1A
MAX378
MAX379
13 IN1B
IN2
IN3
IN2A
IN3A
IN4A
OUTA
12
11
10
9
12
11
10
9
IN5
IN6
IN7
IN8
IN2B
IN3B
IN4B
OUTB
IN4
OUT
DIP
DIP
Pin Configurations continued at end of data sheet.
________________________________________________________________ Maxim Integrated Products
1
Ca ll t o ll fre e 1 -8 0 0 -9 9 8 -8 8 0 0 fo r fre e s a m p le s o r lit e ra t u re .