INTRODUCTION
The CH1788 modem has the smallest footprint and lowest profile of any commercially available full function, FCC Part 68 approved 2400bps modem. Utilizing a 68 pin PLCC form factor and requiring a minimum amount of PCB space (0.95”x0.95”x 0.255”), the CH1788 affords the design engineer maximum flexibility. The CH1788 provides two external interfaces: a CCITT V.24 standard 5 volt serial interface for routing directly to a UART; and a TIP and RING interface for connection to the PSTN telephone line. The CH1788 is compatible with available industry communication software or may be controlled with software commands via an embedded microcontroller.

FEATURES
• Supports data rate standards, CCITT V.22bis,V.22, Bell 212, and Bell 103, Bell 202, V.23.
• Fast connect handshaking.
• FCC Part 68 approved and DOT CSA CS-03 Part I approvable.
• UL 1950 and CSA C22.2 950 Listed.
• AT Command structure.
• Speed buffered operation at: 9600, 2400, 1200 and 300bps.
• Call progress tone detection.
• Caller ID information.
• Line In Use and Priority Pick Up 911 feature support with external circuitry.
• DTMF generation and detection resident on CH1788.
• 5 volt operation/ 3.3 volt operation available.
• Low power operation with automatic reduced power idle and zero power standby modes.
• Low profile PLCC surface mount packaging; fits standard 68 pin PLCC socket.
• Size: 0.95” x 0.95” x 0.255”(nominal).