**ADG608BRU: A Comprehensive Guide to the 8-Channel CMOS Analog Multiplexer**

The **ADG608BRU** is a monolithic, CMOS-based analog multiplexer designed to handle a wide range of signal switching applications. As a member of Analog Devices' extensive switch and multiplexer portfolio, this IC is engineered for high performance, reliability, and versatility, making it a fundamental component in data acquisition systems, communication infrastructure, and automated test equipment.

**Core Architecture and Functionality**

At its heart, the ADG608BRU is an **8-channel single-ended multiplexer**. It features eight independent input channels that can be connected to a single common output (D), determined by the state of a 3-bit binary address (A0, A1, A2). An enable pin (EN) is included to disconnect all channels from the output, placing the device in a high-impedance state, which is crucial for conserving power and simplifying bus sharing in multi-device systems.

Fabricated on an advanced **CMOS process**, the device offers several inherent advantages: extremely low power consumption (typical supply current is just 8 nA), high off-isolation, and very low on-resistance (typically 45 Ω). The **on-resistance is highly flat across the full analog input range**, which is critical for minimizing distortion and signal error in precision applications.

**Key Features and Specifications**

* **Wide Voltage Range:** The ADG608BRU operates from a single supply range of **+2.7 V to +5.5 V**, making it compatible with 3 V and 5 V logic systems. It can also handle bipolar signals when configured with a dual supply up to ±5.5 V.

* **Low Power Consumption:** The CMOS design ensures minimal power draw, a vital characteristic for **battery-powered and portable devices**.

* **Break-Before-Make Switching:** This built-in feature prevents momentary shorting between adjacent input channels during switching, protecting both the multiplexer and the source signals.

* **TTL/CMOS Compatible Digital Inputs:** The control logic inputs are compatible with standard digital signals, ensuring easy interfacing with microcontrollers, FPGAs, and DSPs without requiring level-shifting circuitry.

* **Robust ESD Protection:** The device is rated with a **4 kV ESD protection** (per MIL-STD-883 Method 3015), enhancing its durability in demanding environments.

**Typical Application Circuits**

The primary function of the ADG608BRU is to expand the analog input capabilities of a system. A common application is routing multiple sensor outputs or signal sources to a single analog-to-digital converter (ADC) on a microcontroller. This allows a single, high-precision ADC to digitize numerous signals sequentially, significantly reducing system cost and complexity. It is equally effective in audio signal routing, video switching, and programmable gain amplifier circuits.

**Design Considerations**

When integrating the ADG608BRU into a design, several factors must be considered:

* **Signal Integrity:** The on-resistance (Ron) and its flatness will affect gain error and total harmonic distortion (THD). For high-frequency or high-precision signals, these parameters must be carefully evaluated against system requirements.

* **Supply Decoupling:** Proper decoupling with 0.1 μF ceramic capacitors close to the supply pins is essential for stable operation and noise reduction.

* **Channel Crosstalk:** High off-isolation ensures that signals on disabled channels do not bleed through to the output, maintaining signal integrity.

**ICGOODFIND Summary**

The **ADG608BRU** stands out as an **exceptionally versatile and efficient solution for analog signal routing**. Its combination of a wide operating voltage range, ultra-low power consumption, and robust construction makes it an ideal choice for a vast array of applications, from industrial instrumentation to consumer electronics. By enabling a single ADC to process multiple analog inputs, it simplifies design, lowers overall system cost, and enhances reliability, solidifying its role as a critical component in modern electronic systems.

**Keywords:**

1. **CMOS Analog Multiplexer**

2. **Low On-Resistance**

3. **Low Power Consumption**

4. **Break-Before-Make**

5. **Single/Dual Supply Operation**