Datasheet Details
| Part number | BU8874 |
|---|---|
| Manufacturer | ROHM |
| File Size | 180.42 KB |
| Description | DTMF receiver for telephones |
| Download | BU8874 Download (PDF) |
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Overview: Communication ICs DTMF receiver for telephones BU8874 / BU8874F The BU8874 and BU8874F are DTMF receiver ICs developed for use in telephone answering machines, and convert 16 different types of DTMF signals into 4-bit binary serial data. In addition to a compact 8-pin DIP (BU8874) package, these receivers feature a wide dynamic range, eliminating the need for an external input amplifier. Expertise from a number of companies has been incorporated into these products to enable guard time control through a host microcontroller.
| Part number | BU8874 |
|---|---|
| Manufacturer | ROHM |
| File Size | 180.42 KB |
| Description | DTMF receiver for telephones |
| Download | BU8874 Download (PDF) |
|
|
|
s 203 Communication ICs FInput / output circuits INPUT PWDN BU8874 / BU8874F OSC ACK SD ESt 204 Communication ICs FElectrical characteristics (unless otherwise noted, Ta=25_C, VDD=5.0V) BU8874 / BU8874F 205 Communication ICs FCircuit operation (1) An overview of operation A DTMF signal is supplied to the INPUT pin and applied to a pair of 6th-order bandpass filters, which separate the DTMF signal into its high (COL) and low (ROW) frequencies.
The separated tonesre converted into square waves and fed to a DIGITAL DETECTOR.
The DIGITAL DETECTOR checks the two tones to see if they are within the valid DTMF frequency bands.
| Part Number | Description |
|---|---|
| BU8874F | DTMF receiver for telephones |
| BU8871F | DTMF receiver for telephones |
| BU8872 | DTMF receiver for telephones |
| BU8872FS | DTMF receiver for telephones |
| BU8899GU | Sound Generator |
| BU8241F | Cross point mixer |
| BU8241FS | Cross point mixer |
| BU8242F | Cross point mixer |
| BU8244F | Cross point mixer |
| BU8254GUW | 35bit LVDS Transmitter |