CH2124 Ver la hoja de datos (PDF) - Cermetek Microelectronics

Número de pieza

componentes Descripción

Lista de partido

CH2124

HIGH SPEED INTERNET MODEM FAMILY

Cermetek Microelectronics 

Cermetek Microelectronics, Inc.

Refer to Cermetek’s High Speed Modem and FAX

Family product data sheet for a complete description

of the internal modem’s capabilities and functions.

Serial Host Interface Buffer. The iModem utilizes a

serial V.24 EIA 232-E 5V interface to communicate

with the internal modem and to communicate with the

internal µP.

IMPORTANT NOTICE

If the user wants to change the DTE/Host

communication speed to any speed other than the

factory set speed of 57.6kbps for the CH2156/60 or

2400bps for the CH2124, the user must first change

the DTE speed of the iModem using the appropriate

all @T® commands before changing the DTE/Host

speed. Refer to Application Note # 158, Cermetek

iModem Caveats and Definitions, for a more detailed

discussion of this issue.

Telephone Line Interface or DAA. The iModem

family includes a unique low distortion DAA designed

for optimal performance over all PSTN line conditions

thereby achieving the most reliable and best

performance PSTN connections.

The CH21XX iModem family is designed to meet North

American telephone standards as set by FCC Part 68

(USA) and CSA CS-03 Part I (Canada). Each iModem

product is shipped from the factory with an FCC label

indicating the FCC registration number and ringer

equivalent. The PSTN line interface is UL1950 and

CSA listed. Consequently, the iModem family of

products satisfies U.S. and Canadian requirements,

and will meet other international approval agency

requirements that specify these levels of isolation.

Pins 1 and 2 function as both input and output

connections to the PSTN. To maximize field reliability

in hostile environments, to ensure UL compliance, and

also optionally for FCC part 15 compliance, these two

pins may be routed through an external network such

as that briefly described in figure 3 or as described in

more detail in Cermetek Application Note # 126,

Supplemental PSTN Line Protection.

PHONE LINE CONNECTION GUIDELINES

1. The iModem must be mounted in the final

assembly such that it is isolated from exposure to

any hazardous voltages within the assembly.

Adequate separation and restraint of cables and

cords must be provided.

2. The circuitry from the iModem to the telephone

line interface must be provided in wiring that

carries no other circuitry other than that

High Speed Internet Modem Family

specifically allowed in the FCC rules (such as A

and A1 leads).

3. Connection to the PSTN line should be made

through an RJ-11C jack.

4. PCB traces from the iModem’s RING and TIP

pins to the RJ-11C jack must be 0.1 inch spacing

or greater to one another and 0.2 inch spacing or

greater to all other traces. The traces should

have a nominal width of 0.020 inches or greater.

5. The RING and TIP PCB traces should be as

short as possible and oriented to prevent

coupling with other high speed or high frequency

signals present on the host circuit PCB.

6. No additional circuitry other than that shown in

Figure 3 may be connected between the iModem

module and the RJ-11C jack. Doing so will

invalidate the conveyed FCC approval.

7. The iModem, the RJ-11C jack, the interfacing

circuitry and all PCB traces must be contained on

a PCB with a 94 V-0 flammability rating.

8. The supplied FCC registration label must be

applied visibly on the outside of the product.

9. The product’s User Manual must provide the user

with instructions for connection and use as

recommended in the FCC Registration Section

below.

CANADIAN APPROVALS

The iModem family is approvable for use by DOT to

CSA CS-03 Part I. However, per Canadian

procedures, approval can only be granted after the

iModem has been installed into the end product.

Typically, Canadian approval is obtained by submitting

the final end product to an independent test house or

consultant for evaluation. The test house/consultant

then forwards the test results and applicable

documents to the regulatory agency. Cermetek offers

a list of consultants to assist with this process.

iMODEM HANDLING AND ASSEMBLY

RECOMMENDATIONS

The iModem contains static-sensitive components and

should only be handled by personnel and in areas that

are properly protected against static discharge.

There are two mounting techniques that are

recommended for physically connecting the iModem to

a PCB:

1. Direct soldering.

2. Sockets.

2003 Cermetek Microelectronics, Inc.

Page 6

Document No. 607-0017 Revision G1 (06/03)

Share Link: