Overview
The AD8321ARZ, produced by Analog Devices Inc., is a low-cost, digitally controlled variable gain amplifier. It is optimized for coaxial line driving applications, particularly in cable modems and other high-speed data transmission systems. The device operates from a single +9 V supply and is packaged in a 20-lead SOIC (Small Outline Integrated Circuit) package. The AD8321 is designed to drive a 75 Ω load, such as coaxial cable, and maintains a constant 75 Ω output impedance during power-up and power-down conditions, eliminating the need for external termination.
Key Specifications
| Parameter | Conditions | Min | Typ | Max | Unit |
|---|---|---|---|---|---|
| Gain Range | 52.4 | 53.4 | 54.4 | dB | |
| Maximum Gain | 25.25 | 26 | 26.75 | dB | |
| Minimum Gain | -28.15 | dB | |||
| Input Resistance (Single-Ended) | 820 | Ω | |||
| Input Resistance (Differential) | 900 | Ω | |||
| Input Capacitance | 2.0 | pF | |||
| Output Level (Max Gain, f = 42 MHz) | VCC = +9 V, RL = 75 Ω | 11 | dBm | ||
| Supply Current | VCC = +9 V, TA = +25°C | mA |
Key Features
- Digitally controlled variable gain with a range of approximately 53 dB.
- Operates from a single +9 V supply and is packaged in a 20-lead SOIC package.
- Capable of driving a 75 Ω load, such as coaxial cable, with low distortion and high power output.
- Maintains constant 75 Ω output impedance during power-up and power-down conditions, eliminating the need for external termination.
- Linear-in-dB gain response and high bandwidth operation exceeding 100 MHz at output signal levels over 12 dBm.
- Programmable gain controlled by a three-wire SPI-compatible interface.
Applications
- CATV (Cable Television) line drivers.
- High-speed data modems.
- Interactive CATV set-top boxes.
- CATV plant test equipment.
- General-purpose IF (Intermediate Frequency) variable gain blocks.
Q & A
- What is the AD8321ARZ used for? The AD8321ARZ is used as a digitally controlled variable gain amplifier, particularly in coaxial line driving applications such as cable modems and CATV systems.
- What is the gain range of the AD8321ARZ? The gain range of the AD8321ARZ is approximately 53 dB.
- What type of package does the AD8321ARZ come in? The AD8321ARZ is packaged in a 20-lead SOIC (Small Outline Integrated Circuit) package.
- What is the typical supply voltage for the AD8321ARZ? The typical supply voltage for the AD8321ARZ is +9 V.
- How is the gain controlled in the AD8321ARZ? The gain is controlled by a three-wire SPI-compatible interface.
- What is the maximum output level of the AD8321ARZ at 42 MHz? The maximum output level at 42 MHz is 11 dBm.
- What kind of load can the AD8321ARZ drive? The AD8321ARZ is capable of driving a 75 Ω load, such as coaxial cable.
- Does the AD8321ARZ require external termination? No, the AD8321ARZ maintains a constant 75 Ω output impedance during power-up and power-down conditions, eliminating the need for external termination.
- What are some common applications of the AD8321ARZ? Common applications include CATV line drivers, high-speed data modems, interactive CATV set-top boxes, and CATV plant test equipment.
- What is the bandwidth of operation for the AD8321ARZ? The AD8321ARZ can operate at bandwidths exceeding 100 MHz at output signal levels over 12 dBm.
