ZL490xx is a family of high performance DTMF receivers which decode all 16 tone pairs into a 4-bit binary code. These devices incorporate an AGC for wide dynamic range and are suitable for end-to-end signalling.
The document describes the ZL490xx family of high-performance DTMF (Dual-Tone Multi-Frequency) receivers manufactured by Zarlink Semiconductor. These devices decode all 16 standard tone pairs into a 4-bit binary code and are designed for applications such as telephone answering machines, end-to-end signaling, and fax machines.
The datasheet details the functional blocks including Automatic Gain Control (AGC), energy detection, and serial data output logic. It distinguishes between two sub-families: the ZL490x0 series which requires external software guard time, and the ZL490x1 series which features internal delayed steering for validation. The document also provides pin descriptions, ordering information for various package types (PDIP, SOIC, SSOP), and electrical characteristics.
| Wide Dynamic Range | 50dB |
|---|---|
| Power Supply Voltage | 5V Typ. |
| Operating Temperature Range | -40°C to +85°C |
The devices are suitable for integrated telephone answering machines, end-to-end signalling, and fax machines.
The device provides a wide dynamic range of 50dB.
The device operates with a positive power supply of 5V typical.
The energy detector produces an indication when the signal level is above -35dBm.