Cermetek Microelectronics Inc of Sunnyvale, California has two new telephone line interface circuits, the CH1811 and CH1810A, which have been approved by the Federal Communications Committee, FCC, for voice and data applications. Telephone line interfaces, also referred to as Data Access Arrangements, DAAs, are used to interface data communications circuits such as modem chip sets to the public switched telephone network. Both the CH1811 and CH1810A are available now. The power levels can be adjusted externally in one dBm increments, used in leased line operation. The CH1810A is a smaller, pin-compatible version of the company’s original CH1810 product. It does not require a negative supply voltage and is used on those applications that require data only. FCC and Canadian DOC requirements include high voltage isolation, impedance, surge protection and power level monitoring. Other features found on both components are hook switch control, ring detector, pulse dial capability, squelch control, two-to-four wire conversions and billing delay. The CH1811 costs $54 and the CH1810A is $49 in volumes of 1,000.
Content from our partners
