HIGH SPEED FAMILY OF ULTRA SMALL MODEMS CH2056A /-B / ET-B V.92 / 57,600bps / TBR21 CH1799A /-B / ET-B V.34bis / 33,600bps / TBR21 CH1794A /-B / ET-B V.32bis / 14,400bps / TBR21 FEATURES INTRODUCTION Supports V.92, V.90, V.34bis, V.34, V.32bis, V.23, The CH2056A, CH1799A and CH1794A (HS Modem V.32, V.22bis, V.22A/B, V.23, V.21, Bell 212A and Family) are industrial grade high-speed modem 103. modules. Each HS Modem product supports a range of modem standards and speeds from 300bps to CH2056A supports V.80 Synchronous operation. 14,400bps, 28,800bps, 33,600bps or 57,600bps. By Error correcting: V.42 LAPM, MNP 2-4 and using built in compression algorithms the operation MNP10. MNP10 Data through put enhancement speed can be expanded to the maximum DTE rate of for cellular operation. 57.6kbps for the CH1794A, 115.2kbps for the CH1799A and 230.4kbps for the CH2056A. A choice Data Compression: V.42bis, V.44, and MNP 5 of error correcting schemes is available including MNP DTE serial interface with speeds up to 230.4kbps 10 for cellular telephone applications. The HS Modem (CH2056A), 115.2 (CH1799A) or 57.6kbps family supports Send and Receive FAX. The (CH1794A). CH179XA-L/CH2056A-L and CH179XAR- RoHS Compliant versions available. L/CH2056AR-L operates exclusively on non-voltage bearing leased line. Low Power 3.3V operation: 170mW (nominal). 5V operation: 300mW (nominal). The HS Modem family is pin compatible with Cermeteks low cost CH1786A V.22bis, 2400bps Automatic baud rate adaptability utilizing speed modem family. Each module in the HS Modem family sensing, flow control and data buffers. is a self-contained modem and is FCC Part 68 DTMF Encoding and Decoding. approved (pending) and Industry Canada approved Send & Receive FAX class 1, Group 3 supported. (pending). Additionally, the CH179XA/CH2056A- B/ET-B and the CH1799AR/CH2056AR-B/ET-B Serial V.24 interface: 5V tolerant. products meet the European TBR21 requirements. NVRAM directory and stored profiles. These ultra small modules are designed for PCB AT Command structure, with extensions. through-hole mounting and are 1.01 x 1.27 x 0.52 Built-in DAA with 1500 VAC RMS isolation 2122V (nominal) in size. The HS Modem family requires only peak surge protection. two external interfaces: a ITU-T V.24 serial interface UL 60950 and CSA C22.2 950 Recognized for direct access to a UART, and a Tip and Ring RJ- (E251266) (pending). 11C Jack for the PSTN line connection. The HS Modem can be controlled with industry standard AT FCC Part 68 approved (pending): commands and is compatible with available industry US:B46MM07BCHXXXXAYY. communication software. Industry Canada CS-03 Part I Registered (pending): DESCRIPTION OF FUNCTIONAL BLOCKS IC:176A-CHXXXXAY. AND DISCUSSION OF BASIC OPERATIONS PCM upstream (V.92 only). Figure 1 contains a functional block drawing of the HS Modem family of products. Each HS Modem product Modem-on-Hold (V.92 only). consists of a serial interface buffer, Quick Connect (V.92 only). modulator/demodulator, modem controller with error Size: 1.01 x 1.27 x 0.52 (nominal). correction and data compression, non-volatile RAM and a DAA. Pin compatible with low speed CH1786A. Fast Connect (V.22). Serial Host Interface Buffer. The HS Modem utilizes Caller ID (optional). a serial V.24 EIA 232-E 5V interface to control the modem. The HS Modem products can communicate Zero Power (optional). over the serial interface with the Data Terminal Off-Hook Indication (optional). Equipment (DTE) at a fixed speed regardless of the carrier line modulation speed (DCE) of the PSTN Leased Line version available. modem connection. This eliminates the need to have TBR21 Compliant version available. 2007 Cermetek Microelectronics, Inc. Page 1 Document No. 607-0020 Revision B (01/07) Cermetek Microelectronics, Inc. CH179XA/2056A High Speed Family of Ultra Small Modems the DTE step up or step down in speed based on the The HS Modem family is designed to meet North in-coming or out-going PSTN communication data American telephone standards as set by the FCC Part rate. Hence, the DTE can train the CH2056A, to say 68 (USA) and CSA CS-03 Part I (Canada). Among the 56kbps, and talk to a slower in-coming data more critical parameters, the PSTN line interface is connection at say, 2400bps without changing host designed to meet 1500 VAC RMS isolation and speed. Conversely, the host DTE trained at 14.4kbps provide 2122V peak surge protection. Consequently, can also communicate with the modems at higher the HS Modem family of products satisfies U.S. and speeds, say 28.8kbps. This is accomplished by Canadian requirements, and will meet other invoking internal automatic data flow control. The HS international approval agency requirements that Modem family has a resident buffer to allow for this specify these levels of isolation. auto baud operation. Pins 1 and 2 function as both input and output connections to the PSTN. To maximize field reliability in hostile environments, for Canadian approval, for UL compliance, and also optionally for FCC Part 15 compliance, these two pins must be routed through an external network such as that briefly described in Figure 6A and described in more detail in Cermetek Application Note 126. Each HS Modem product comes with FCC Part 68 approval and is shipped from the factory with an FCC Label indicating registration number and ringer equivalent. This label should be prominently displayed on the end product. Canadian approval for CH1799A is listed on page 1. Canadian approvals for other products in Cermeteks High Speed Modem Family are available upon request. With the exception of the U.S. Figure 1. Functional Block Diagram of HS Modem and Canada, most countries require submission of the Family. final product or system containing the HS Modem to the appropriate governing regulatory agency for Non-Volatile RAM (NVRAM). NVRAM can store approval. Typically this is accomplished by submitting user-customized configurations. The AT&Wn the final end product to an independent test house or command will store the active modem configuration in consultant for evaluation. The test house/consultant one of two NVRAM locations as selected by an n of 0 then forwards the test results and applicable or 1. The AT&Yn command selects one of the stored documents to the regulatory agency. Contact modem configurations to be automatically recalled and Cermetek for a list of suggested consultants. made active upon reset or power up. The ATZn command immediately recalls and activates a stored Modulation/Demodulation/Error Correcting and configuration. See Table 6 for storable S-Registers Data Compression. These functions are provided by and Commands. an industry standard modem chip set which has been adapted for use with the HS Modem family. The The NVRAM can save up to four telephone numbers, Modulation/Demodulation scheme supports line with up to 31 digits or modifiers in each telephone equalization, forward error correction and the industry number. The AT&Zn=s command will store s, the modem standards listed below. telephone number dial string. The ATDS=n command will cause the modem to dial one of the four stored telephone numbers. The NVRAM storage location for SUPPORTED MODULATION STANDARDS the four telephone numbers is selected by an n of 0, 1, Bell 103 ITU-T V.22 2, or 3. Bell212A ITU-T V.22bis ITU-T V.32 Telephone Line Interface or DAA. High performance ITU-T V.32bis modems are extremely sensitive to DAA (Data Access ITU-T V.34 Arrangement) performance. The difference between a ITU-T V.34bis good modem and a fair one is in the DAA ITU-T V.90 performance. The HS Modem family includes a ITU-T V.92 unique low distortion DAA designed for optimal performance over all PSTN line conditions thereby achieving the most reliable and best performance PSTN connections. 2007 Cermetek Microelectronics, Inc. Page 2 Document No. 607-0020 Revision B (01/07)