Audio ICs
VSC∗ system processor IC
BA1701
The BA1701 is a monolithic audio-compression system controller IC that uses VSC∗. When used in combination with an analog delay circuit and low-pass filter, it can replay recorded audio at 1 to 2.5 times the recording speed, without altering the pitch.
FApplications Audio compression systems for tape-based answering machines and learning aids
FFeatures 1) Wide operating voltage range (4.5V to 14V). 2) Built-in two-phase sweep oscillator that can direc.
VSC system processor IC
Audio ICs
VSC∗ system processor IC
BA1701
The BA1701 is a monolithic audio-compression system controller IC that uses VSC∗. When used in combination with an analog delay circuit and low-pass filter, it can replay recorded audio at 1 to 2.5 times the recording speed, without altering the pitch.
FApplications Audio compression systems for tape-based answering machines and learning aids
FFeatures 1) Wide operating voltage range (4.5V to 14V). 2) Built-in two-phase sweep oscillator that can directly drive BBD.
3) Built-in motor controller is synchronized with the audio compression ratio. 4) Built-in voltage regulator.
FAbsolute maximum ratings (Ta = 25_C)
FRecommended operating conditions (Ta = 25_C)
∗ VSC is a trademark of The Variable Speech Control Company. This product is manufactured under licence from VSC Ltd. for use in VSC systems.
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Audio ICs
FBlock diagram
BA1701
FElectrical characteristics (unless otherwise noted, Ta = 25_C, VCC = 6V, f = 1kHz, and VIN = 1.5VP-P)
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Audio ICs
FMeasurement circuit
BA1701
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Audio ICs
FApplication example
BA1701
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Audio ICs
FCircuit operation (1) System construction The BA1701 is a monolithic audio-compression system controller IC that uses VSC.When used in combination with an analog delay circuit, low-pass filter, and tape speed controller, it can replay recorded audio at 1 to 2.5 times the recording speed, without altering the pitch (see
BA1701
Fig. 3). The BA1701 has a built-in motor driver control circuit t.