Datasheet

MAX349/MAX350
Serially Controlled, Low-Voltage,
8-Channel/Dual 4-Channel Multiplexers
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Pin Description
Note: NO and COM pins are identical and interchangeable. Either may be considered as an input or an output; signals pass equally
well in either direction.
• • •
• • •
• • •
• • •
• • •
SCLK
DIN
DOUT
COM-OUT
CS
t
DO
t
DH
t
DS
t
CSS
t
CH
t
CL
t
CSH2
t
ON
,
t
OFF
• • •
Figure 1. Timing Diagram
1 Serial Clock Digital Input
2 Positive Analog Supply Voltage Input
3 Serial Data Digital Input
5 Common Analog Switch (mux output)
6–13 Normally Open Analog Switch Inputs 0–7
— Common Analog Switch “A” (mux output)
— Normally Open Analog Switch “A” Inputs 0–3
— Normally Open Analog Switch “B” Inputs 0–3
— Common Analog Switch “B” (mux output)
4
Ground. Connect to digital ground. (Analog signals have
no ground reference; they are limited to V+ and V-.)
1 SCLK
2 V+
3 DIN
5 COM
6–9, 11–14 NO0–NO7
— COMA
— NO0A–NO3A
— NO3B–NO0B
— COMB
4 GND
15
Negative Analog Supply Voltage Input. Connect to GND
for single-supply operation.
16 Serial Data Digital Output. Output high is V+.
17
RESET Input. Connect to logic high (or V+) for normal operation.
Drive low to set all switches off and set internal shift registers to 0.
18 Chip-Select Digital Input (Figure 1)
17 V-
18 DOUT
19
RESET
20
CS
14 No Connect, not internally connected.10, 15, 16 N.C.
MAX349
SSOPDIP/SO
NAME FUNCTION
1
2
3
—
—
5
6–9
10–13
14
4
1
2
3
—
—
5
6–9
11–14
15
4
15
16
17
18
17
18
19
20
— 10, 16
MAX350
SSOPDIP/SO
PIN