Logic - Signal Switches, Multiplexers, Decoders

Part Number	Description / PDF	Quantity
HI4-0516-8/B Rochester Electronics	HI4-0516-8/B	384
54LS258B/BEA Rochester Electronics	DUAL MARKED (M38510/30907BEA)	198
5447/BEA Rochester Electronics	DUAL MARKED (M38510/01007BEA)	251
54F151/B2A Rochester Electronics	DUAL MARKED (M38510/33901B2A)	912
54HC152J/B Rochester Electronics	8 TO 1 LINE DATA SELECTORS/MULTI	0
54LS155A/BEA Rochester Electronics	DUAL MARKED (M38510/32601BEA)	740
54LS158/BEA Rochester Electronics	DUAL MARKED (M38510/30904BEA)	114
54F257/B2A Rochester Electronics	DUAL MARKED (M38510/33906B2A)	643
54HC298J/B Rochester Electronics	QUAD 2-INPUT MULTIPLEXER	465

Logic - Signal Switches, Multiplexers, Decoders

1. Overview

Signal switches, multiplexers, and decoders are fundamental logic ICs used to manage signal routing and data selection in electronic systems. Signal switches control the flow of electrical signals, multiplexers select between multiple input signals, and decoders convert encoded signals into specific outputs. These components are critical in modern technologies such as telecommunications, computing, and industrial automation, enabling efficient data handling and system design simplification.

2. Main Types and Functional Classification

Type	Functional Features	Application Examples
Signal Switches	Digital/analog switches with on/off control	Audio routing, power management
Multiplexers (MUX)	2:1 to 16:1 channel selection, data bus sharing	Network switches, sensor data aggregation
Decoders	Binary-to-decimal, BCD-to-7-segment conversion	Memory address decoding, display drivers

3. Structure and Composition

These ICs typically use CMOS or TTL technology with standard packages like DIP, SOP, and QFN. Internal components include transistor arrays, logic gates, and channel control circuits. For example, a 4-channel analog switch integrates four independent switching elements in a single package with common control lines.

4. Key Technical Specifications

Parameter	Description	Importance
On-resistance (R_ON)	Resistance in conducting state	Impacts signal integrity
Bandwidth	Maximum signal frequency supported	Determines high-speed capability
Channel count	Number of independent paths	System scalability
Power consumption	Quiescent current and switching loss	Battery life consideration
Propagation delay	Signal transmission time	Critical for timing-sensitive systems

5. Application Areas

Telecommunications: Signal routing in base stations
Automotive: Sensor signal selection in ECUs
Consumer Electronics: HDMI switch boxes
Industrial: PLC signal conditioning
Computing: Memory address decoding in CPUs

6. Leading Manufacturers and Products

Manufacturer	Representative Product	Key Features
TI	SN74CB3Q3245	10- R_ON, 2.3V-3.6V supply
Analog Devices	ADG1412	4-channel switch, 165MHz bandwidth
NXP	74HC151	8:1 multiplexer, 70MHz operation
STMicroelectronics	CD4028BE	BCD-to-decimal decoder, 18V rating

7. Selection Guidelines

Channel requirements: Match input/output count needs
Signal type: Choose analog/digital switches accordingly
Voltage compatibility: Ensure supply voltage matches system rails
Speed vs. power trade-off: High bandwidth increases consumption
Package constraints: Consider PCB space and thermal requirements

8. Industry Trends

Current developments focus on miniaturization (0.4mm pitch packages), lower on-resistance (<1 ), and integration with level-shifting functions. The rise of IoT and 5G drives demand for high-frequency switches (up to 10GHz) with sub-mW standby power. Advanced CMOS processes enable higher channel density while maintaining signal integrity in automotive-grade temperature ranges.