Dual Audio Analog Switches

FEATURES

• “Clickless” Bilateral Audio Switching
• Guaranteed “Break-Before-Make” Switching
• Low Distortion: 0.003% typ
• Low Noise: 1 nV/√Hz
• Superb OFF-Isolation: 120 dB typ
• Low ON-Resistance: 60 V typ
• Wide Signal Range: VS = 618 V; 10 V rms
• Wide Power Supply Range: 620 V max
• Available in Dice Form

GENERAL DESCRIPTION 
The SSM2402/SSM2412 are dual analog switches designed specifically for high performance audio applications. Distortion and noise are negligible over the full audio operating range of 20 Hz to 20 kHz at signal levels of up to 10 V rms. The SSM2402/ SSM2412 offer a monolithic integrated alternative to expensive and noisy relays or complex discrete JFET circuits. Unlike conventional general-purpose CMOS switches, the SSM2402/SSM2412 provide superb fidelity without audio “clicks” during switching. Conventional TTL or CMOS logic can be used to control the switch state. No external pull-up resistors are needed. A “T” configuration provides superb OFF-isolation and true bilateral operation. The analog inputs and outputs are protected against overload and overvoltage. An important feature is the guaranteed “break-before-make” for all units, even IC-to-IC. In large systems with multiple switching channels, all separate switching units must open before any switch goes into the ON-state. With the SSM2402/ SSM2412, you can be certain that multiple circuits will all break-before-make. The SSM2402/SSM2412 represent a significant step forward in audio switching technology. Distortion and switching noise are significantly reduced in the new SSM2402/SSM2412 bipolar JFET switches relative to CMOS switching technology. Based on a new circuit topology that optimizes audio performance, the SSM2402/SSM2412 make use of a proprietary bipolar JFET process with thin-film resistor network capability. Nitride capacitors, which are very area efficient, are used for the proprietary ramp generator that controls the switch resistance transition. Very wide bandwidth amplifiers control the gate-to-source voltage over the full audio operating range for each switch. The ON-resistance remains constant with changes in signal amplitude and frequency, thus distortion is very low, less than 0.01% max. The SSM2402 is the first analog switch truly optimized for high-performance audio applications. For broadcasting and other switching applications which require a faster switching time, we recommend the SSM2412—a dual analog switch with one-third of the switching time of the SSM2402.
 

Posted in: Analog Multiplexer , Audio Analog Switch , Guitar Loop