Dual 4-channel, Triple 2-channel Analog Multiplexers/Demultiplexers/ # Technical Documentation: HD74HC4052 Dual 4-Channel Analog Multiplexer/Demultiplexer
Manufacturer : HIT (Hitachi, now part of Renesas Electronics)
Component Type : High-Speed CMOS Logic, Analog Switch/Multiplexer
Package Options : DIP-16, SOP-16, TSSOP-16
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## 1. Application Scenarios
### Typical Use Cases
The HD74HC4052 is a dual 4-channel analog multiplexer/demultiplexer with digital control, designed to handle both analog and digital signals. Its primary function is to route one of four input signals to a common output (multiplexing) or distribute one input to one of four outputs (demultiplexing) for each of its two independent sections.
Key operational modes include:
- Signal Routing in Test Equipment : Selecting between multiple sensor inputs or signal sources for measurement by a single ADC or amplifier channel.
- Audio Signal Switching : In audio mixers or effects units, to choose between different audio input sources (e.g., microphones, instruments) for processing.
- Communication Systems : Channel selection in frequency-hopping or multi-standard radio systems.
- Programmable Gain Amplifiers (PGAs) : Switching between different feedback resistor networks to alter amplifier gain.
- Data Acquisition Systems (DAQs) : Multiplexing multiple analog sensor outputs (temperature, pressure, voltage) into a single analog-to-digital converter (ADC).
### Industry Applications
- Industrial Automation : Used in PLC I/O modules to multiplex analog sensor signals from various process points (temperature, flow, pressure).
- Automotive Electronics : In infotainment systems for switching audio sources (radio, Bluetooth, AUX) or in body control modules for reading multiple analog sensors.
- Medical Devices : For selecting different bio-potential signals (ECG, EEG) in patient monitoring equipment.
- Consumer Electronics : Found in smart home hubs to interface with various analog environmental sensors.
- Telecommunications : In base station equipment for RF signal path switching or filter bank selection.
### Practical Advantages and Limitations
Advantages:
- Low Power Consumption : Typical `I_CC` of 4 µA (static) due to CMOS technology, suitable for battery-powered devices.
- Wide Analog Voltage Range : Can handle analog signals from `V_EE` to `V_CC`. With `V_CC = +5V` and `V_EE = -5V`, it accommodates bipolar signals up to ±5V.
- High-Speed Operation : Typical propagation delay of 10 ns (`V_CC = 5V`), enabling use in moderate-speed data acquisition.
- Low "On" Resistance : Typically 70 Ω (max 180 Ω at `V_CC-V_EE = 4.5V`), minimizing signal attenuation.
- High Off Isolation : Typically -70 dB at 1 MHz, reducing crosstalk between inactive channels.
- Break-Before-Make Switching : Prevents momentary shorting between channels during switching.
Limitations:
- Limited Current Handling : Maximum continuous current through a switch is 25 mA; not suitable for power switching.
- Bandwidth Constraint : Typical -3 dB bandwidth of ~40 MHz; performance degrades for very high-frequency signals (>10 MHz).
- On-Resistance Variation : `R_ON` varies with supply voltage and analog signal level, causing non-linear distortion in precision applications.
- Charge Injection : Typically 5 pC, which can cause voltage glitches when switching, critical in sample-and-hold circuits.
- Voltage Headroom : The analog signal must remain within `V_EE` to `V_CC`; exceeding this can latch up the device or cause damage.
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