The AD8327 is a low-cost, 160MHz bandwidth, 5V supply operation, digitally controlled gain CATV line driver. It meets the DOCSIS standard for reverse path transmission. The device provides 0.3dB to 48.16dB gain, programmed in 6.02dB gain steps. The AD8327 supports SPI interface, and has sleep and transmit enable modes.
The AD8327 is a digitally controlled variable‑gain amplifier optimized for coaxial line‑driving applications such as cable modems that meet the DOCSIS upstream standard. It provides an 8‑bit gain word for a 48.16 dB range, low distortion up to 60 dBmV output, and maintains a constant 75 Ω output impedance during transmit enable and disable modes.
The device operates from a single 5 V supply, supports SPI programming, and is packaged in a 20‑lead TSSOP. It is intended for use as the upstream power amplifier in DOCSIS‑certified cable modems and set‑top boxes, with features such as sleep mode (5 mA quiescent current) and wide temperature range (‑40 °C to +85 °C).
| Gain Range | 48.16 dB |
|---|---|
| Gain Step Size | 6.02 dB per major carry |
| Bandwidth (-3 dB) | 160 MHz |
| Supply Voltage Range | 4.75 V to 5.25 V |
| Quiescent Current (Sleep Mode) | 5 mA |
| Operating Temperature | ‑40 °C to +85 °C |
| Input Impedance (Single‑Ended) | 800 Ω |
The AD8327 provides a programmable gain range of about 48.16 dB.
It operates from a 5 V supply with an acceptable range of 4.75 V to 5.25 V.
In sleep mode the quiescent current is reduced to about 5 mA.