In the world of electronics, there are two fundamental types of signal processing: you either change a signal (like an amplifier does) or you route it. The ADG732BCPZ is a master of the latter. It is a 32-channel, single-ended analog multiplexer that acts as a high-speed, precision switchboard for analog signals.
If you are building a data acquisition system that needs to read 32 different sensors with a single Analog-to-Digital Converter (ADC), or if you are designing a piece of automated test equipment, the ADG732 is likely on your shortlist. It is a modern CMOS workhorse that offers low on-resistance, fast switching, and the flexibility of single or dual-supply operation.
Here is everything you need to know about this versatile chip.
What is a Multiplexer?
A multiplexer (or "Mux") is a device that selects one of several analog or digital input signals and forwards the selected input into a single line. Think of it as a digitally controlled rotary switch. The ADG732 specifically is a 32-to-1 multiplexer, meaning it can connect any one of its 32 input pins (S1 through S32) to a single common output pin (D). The selection is made using a 5-bit binary address (A0 through A4), which allows you to choose any of the 32 channels.
Key Features of the ADG732BCPZ
The ADG732BCPZ is not just any multiplexer; it is designed for precision and speed. Its standout features include:
Low On-Resistance: The switch is incredibly efficient, with a typical on-resistance of just 4 Ω (at 25°C with a +5V single supply or ±2.5V dual supply). More importantly, this resistance is very flat (0.5 Ω flatness) across the entire signal range, which is critical for maintaining signal accuracy.
Fast Switching: It boasts a typical transition time of 23 ns, making it suitable for high-speed data acquisition and communication systems.
Flexible Power Supply: It can operate from a single 1.8V to 5.5V supply or a dual ±2.5V supply. This makes it compatible with everything from modern low-voltage microcontrollers to legacy ±5V analog systems.
Rail-to-Rail Operation: The input signal range can extend to the power supply rails, and it can operate as both a multiplexer and a demultiplexer.
Break-Before-Make Switching: This essential feature prevents momentary shorting between channels when switching, ensuring glitch-free operation.
Microprocessor-Friendly: On-chip latches and TTL/CMOS-compatible inputs make it easy to interface with standard microcontrollers and DSPs.
Compact Package: It is available in a space-saving 48-lead LFCSP (7mm x 7mm) package, ideal for dense PCB designs.
Applications
The ADG732BCPZ is a problem-solver for systems that need to manage many analog signals. Its primary applications include:
Data Acquisition Systems: The classic use case. You have 32 sensors (temperature, pressure, strain gauges) and one expensive ADC. The ADG732 lets you sequentially sample each sensor without needing 32 separate ADCs.
Automatic Test Equipment (ATE): In manufacturing, you need to test multiple points on a circuit board quickly. The ADG732 routes test signals and measurement equipment to different nodes rapidly.
Medical Instrumentation: Used in patient monitoring systems to scan multiple electrodes or sensors (like in ECG or EEG machines) with high fidelity and low noise.
Audio and Video Switching: Its low distortion and high input impedance make it suitable for routing audio and video signals in professional equipment.
Relay Replacement: Solid-state switches like the ADG732 are faster, smaller, and more reliable than mechanical relays for signal routing.
Battery-Powered Systems: Its low power consumption (20 µA typical supply current) makes it ideal for portable and remote sensing devices.
Technical Specifications
The following table summarizes the key technical parameters of the ADG732BCPZ. These specifications are for the device at 25°C unless otherwise noted.
