The Data Access Arrangements (DAA) are required by all semiconductor FAX and modem chip sets. They are used to connect the FAX, modem or voice circuit to the Public Switched Telephone Network (PSTN). In most cases, the modem chip set can be directly or AC coupled to the DAA, which in turn can be directly connected to Tip and Ring of the telephone line.

These circuits must be approved by the governmental agency that oversees the PSTN. The telephone interface series of components have been designed to either eliminate the delay and risk of the registration process or reduce it to a simple filing process, thus allowing a quick to market design-in solution.

Cermetek's DAA line is well suited for most data and voice transmission applications where a small module size and quick design are important criteria. The CH1837A and CH1840 also offer the same pin-out.

DAA Products Common Features

• Provides isolation barrier between low voltage analog signals and PSTN
• 1500V isolation or greater
• Voice and/or data analog signals for 14.4K bps/V.32 bis, V.34
• Ring detection
• Small and ultra small packages
• Single +5V operation
• Internal 2-wire to 4-wire converter
• UL recognized

Product Features CH1837 A V.34 DAA 1.5 KV isolation Excellent voice/data performance 2-wire to 4-wire converter Ideal for internet VoIP applications

Refer to the CH1837A DAA Module Data Sheet for more information.

CH1840 V.32 DAA 1.5 KV isolation FCC Part 68 pre-approved Available Options Extended Temperature -40ºC to +85ºC Version 0 dbs Version 0 dbs, Extended Temperature -40ºC to +85ºC Version

Refer to the CH1840 Module Data Sheet for more information.

Product Description For Pricing CH1837A Low cost V.34 DAA for VoIP Internet Apps Contact Us CH1840 FCC Registered DAA Contact Us CH1840 ET Extended Temperature -40ºC to +85ºC Contact Us CH1840 D 0 dbs Contact Us CH1840 D ET Extended Temperature -40ºC to +85ºC Contact Us CH1817 Modem / Voice Contact Us