CH1788 Cermetek Microelectronics, CH1788 Datasheet
CH1788
Specifications of CH1788
Related parts for CH1788
CH1788 Summary of contents
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... Canadian DOT approvable. An FCC label is supplied. The CH1788 also meets UL 1950 Edition 3 requirements. The CH1788 family of modems operate from a 5 volt DC supply (3.3 volt devices are available by special order). The combination of low power operation, zero power standby mode and small form factor make the CH1788 an ideal choice for portable equipment applications ...
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... FCC Part 68 conveyed approval (see Figure 3 of this document). supplemental protection also improves field reliability and facilitates FCC part 15 approval. SUPPORTED FEATURES AT Command Set. Internal to the CH1788 command interpreter. AT commands and their associated S-registers provide macro functionality. These commands are summarized in this document and are detailed in Cermetek publication CH1788 AT Command and S-Register Reference Guide ...
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... CH1788 to malfunction or to function erratically. Recommendation. To reduce the effects of supply noise recommended that by-pass capacitors be placed on the power supply as close to the CH1788’s supply input (i.e., Pin 20) as practical. Tantalum capacitor in parallel with a 0.01 µF ceramic is recommended. ...
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... This feature is enabled via register S95. Setup. CID requires additional external circuitry network must be added to the CH1788 V+ and V- pins. See Schematic 4 for details. must be set to 8 (the default value) to receive the CID information ...
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... Optional Input. Active high. Used when implementing the 911 Priority Pick- circuit or the Line In Use circuit. Off-Hook. Active low. OH Indicates when the CH1788 is Off-Hook. Used in Line Use, 911 Priority Pick-Up applications and for Audio Control. Request To Send. Active low. Used for optional flow control. Used in conjunction ...
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... The RST pin must be returned LOW for normal operation to Telephone connection requires an active public switched telephone line Telephone connection requires an active public switched telephone line Page 6 CH1788 Surface Mount PLCC 2400bps Modem Note that the CH1788 is FCC Note that the CH1788 is FCC . Also pp Document No. 607-0018 Revision A6 (01/06) ...
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... This feature will work with any compatible modem. Setup: Originate Mode. The Fast Connect feature, when the CH1788 is in originate mode, is activated by using the following command setup string: Enter: ATFY0X4K0S30=$10S89=$40<CR> Result: OK Setup: Answer Mode. The Fast Connect feature, ...
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... HEX 0D). Training the Modem. The CH1788 must be trained to set the DTE speed (i.e., to match its host’s speed and parity) so that the CH1788 is able to recognize serial asynchronous commands sent the host’s UART. The host must retrain the CH1788 each time a reset is performed. ...
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... CARRIER 1200 47 CARRIER 2400 2006 Cermetek Microelectronics, Inc. in this state, the CH1788 will not receive data from the remote modem. Result Codes. After execution command and at the completion of each dial attempt, the CH1788 will deliver a status message on RXD. Referring to Table 3, the message can be a Terse (numeric) or Verbose (English) message ...
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... S69 S86 S89 S95 S110 S111 Automatic Answering. number of rings that the CH1788 must detect before it will answer. S0 may range in value from 0 to 255 NOT ANSWER TELEPHONE S0 =1 ANSWER ON RING ANSWER ON RING ANSWER ON RING 3 S0 =255 ANSWER ON RING 255 When S0 is set to 0, the modem will not answer. ...
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... Adequate separation and restraint of cables and cords must be provided. 2. The circuitry from the CH1788 to the telephone line interface must be provided in wiring that carries no other circuitry specifically allowed in the FCC rules. ...
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... Cermetek Microelectronics, Inc. In addition to restriction notification, the FCC requires that Cermetek make all repairs to the CH1788. If repairs are necessary after installation of the CH1788 in the end product and the end product has been delivered to the end user, the end product must be returned to the end product supplier where the CH1788 can be removed and then forwarded to Cermetek for repair ...
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... Cermetek Microelectronics, Inc. Figure 3. PSTN Line Interface for all CH1788 Products. 1. Current Limiting PSTN Protection Line Device. Current limiting devices are mandatory to meet UL safety standards. To maintain conveyed FCC Part 68 approval, the current limiting components identified as F1 and F2 in dashed Box 1 must be included ...
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... Cermetek Microelectronics, Inc. 2006 Cermetek Microelectronics, Inc. CH1788 Surface Mount PLCC 2400bps Modem Page 14 Document No. 607-0018 Revision A6 (01/06) ...
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... Cermetek Microelectronics, Inc. 2006 Cermetek Microelectronics, Inc. CH1788 Surface Mount PLCC 2400bps Modem Page 15 Document No. 607-0018 Revision A6 (01/06) ...
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... Cermetek Microelectronics, Inc. 2006 Cermetek Microelectronics, Inc. CH1788 Surface Mount PLCC 2400bps Modem Page 16 Document No. 607-0018 Revision A6 (01/06) ...
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... Cermetek Microelectronics, Inc. 2006 Cermetek Microelectronics, Inc. CH1788 Surface Mount PLCC 2400bps Modem Page 17 Document No. 607-0018 Revision A6 (01/06) ...
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... Cermetek Microelectronics, Inc. 2006 Cermetek Microelectronics, Inc. CH1788 Surface Mount PLCC 2400bps Modem Page 18 Document No. 607-0018 Revision A6 (01/06) ...
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... Cermetek Microelectronics, Inc. 2006 Cermetek Microelectronics, Inc. CH1788 Surface Mount PLCC 2400bps Modem Page 19 Document No. 607-0018 Revision A6 (01/06) ...
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... Cermetek Microelectronics, Inc. 2006 Cermetek Microelectronics, Inc. CH1788 Surface Mount PLCC 2400bps Modem Page 20 Document No. 607-0018 Revision A6 (01/06) ...
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... Cermetek Microelectronics, Inc. Table 7. CH1788 System Data Mode Compatibility Specifications. Parameter Specification Asynchronous 2400, 1200 asynchronous. 300 bps asynchronous Asynchronous TXD may differ +/-2.5% from Speed Range modem output. corrected by adding/ deleting stop bits. Asynchronous 10 bits, including start, stop, Format parity. ...
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... Input Leakage Current – All Pins IN V High Level @ -4mA 5V and 3. Low Level @ 4mA OL CH1788 VCC = 5V ± 10%, Temp = 0°C to 70°F. Test conditions: CH1788-3 VCC = 3.3V ± 10%, Temp = 0°C to 70°F *Output Load = 30 pF ± one TTL. Parameter Minimum Off Hook Impedance Trans Hybrid Loss ...
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... Harmonic Distortion Call Progress 120 Passband Frequency Wait Time for Dial tone 2 Return loss @ 1000Hz Table 11. Summary CH1788 Family of Products. Model CH1788 5V, Full function, FCC Part 68 approved, UL 1950 Listed, Hermetic CH1788ET 5V, Full function, FCC Part 68 approved, UL 1950 Listed, Hermetic CH1788-3 3.3V, Full function, FCC Part 68 approved, UL 1950 Listed, Hermetic CH1788-3ET 3 ...
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... Cermetek Microelectronics, Inc. 1. All dimensions indicated are nominal and listed in inches. 2. SMD solder landing pads: 0.120 inches x 0.025 inches. Figure 4. Recommended CH1788 PCB Layout Footprint. 2006 Cermetek Microelectronics, Inc. CH1788 Surface Mount PLCC 2400bps Modem Note Page 24 Document No. 607-0018 Revision A6 (01/06) Package Outline ...
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... Active Low 2006 Cermetek Microelectronics, Inc. Table 12. CH1788 Pin Functions. PACKAGE CONNECTION TABLE FUNCTION PIN NO RTS* RI* CTS* DSR* DCD* DTR* A2* TXD RST Page 25 CH1788 Surface Mount PLCC 2400bps Modem Dimension MIN TYP a 0.250 0.255 b 0.985 0.990 c 0.945 0.950 d 0.825 0.830 e 0.045 0.050 f 0 ...
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... BORREGAS AVENUE | SUNNYVALE CA 94089 CERMETEK WEB SITE: 2006 Cermetek Microelectronics, Inc. | LOCAL: 408-752-5000 | TOLL FREE: 1-800-882-6271 http://www.cermetek.com sales@cermetek.com | EMAIL: Page 26 CH1788 Surface Mount PLCC 2400bps Modem Printed in U.S.A | FAX: 408-752-5004 Document No. 607-0018 Revision A6 (01/06) ...