CH1837A Cermetek Microelectronics, CH1837A Datasheet
CH1837A
Specifications of CH1837A
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CH1837A Summary of contents
Page 1
... For those applications not requiring a two to four wire hybrid converter circuit, the CH1838A provides all the features of the CH1837A (except the hybrid converter) while offering some cost savings. CH1838A is a special order product only. Cermetek for availability and delivery. ...
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... Sensitivity: 38Vrms across TIP and RING Figure 3. Typical Application. Hook Switch Control. The OFFHK input is used to toggle the CH1837A/8A from On-Hook to Off-Hook and back to On-Hook. When the OFFHK input is TTL Low, the CH1837A/8A is On-Hook. The On-Hook state indicates to the CO that the CH1837A/8A is ready to receive calls. ...
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... Connect to the PSTN line through a standard FCC approved RJ-11C jack or equivalent. For RJ-11, use the two center pins. 3. All PCB traces from the CH1837A/8A TIP and RING pins must be at least 0.1 inch spacing from all other traces or other conducting material. The ...
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... When using sockets, steps should be taken to assure that the DAA module remains tightly seated in the socket after the end product is shipped. recommended that some type of mechanical restraint be provided to keep the CH1837A/8A seated to avoid any possibility that the CH1837A/8A works loose during shipment. See Application Note # 130, Summary of Recommended Suppliers for a list of recommended socket manufacturers ...
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... GROUND. Supply line noise should be less than 50mV peak to peak. Note: 1. When answering incoming calls in response to a ring indication on RI, internal degradation may occur if OFFHK is set HIGH before RI returns to its HIGH state. 2. For CH1837A, the RI output is 2X the frequency of the incoming ring signal. PIN I/O CH1838A ...
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... Trans-Hybrid Loss Transmit Input Impedance Receive Output Impedance Ring Select Sensitivity Hook Switch Control Current Weight Supply Current Ringer Equivalence 2004 Cermetek Microelectronics, Inc. Table 3. CH1837A/8A Electrical Specifications. Conditions IOH=0.05mA IOL=2.0mA CH1837A/8A CH1837A/8A Attenuation between the transmitter input PSTN line at 1 ...
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... FCC Part 68 approval or UL60950 listing provide adequate EMI/RFI suppression, B. Capacitors C1 and C2 should not exceed contacting DOT Page 7 CH1837A/8A Data Access Arrangement Module approval and to maintain UL60950/3 listing. suppressors are adequate. environments, use an external 3 terminal device (as indicated in Figure 5) with an earth ground. ...
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... DAA, FCC Part 68 Compliant, UL60950/3 Special Order Option to Standard CH1837A product. Notes: 1. Pins are 0.010 inches X 0.020 inches. *2. Nominal pin length is 0.200 inches for CH1837A/8A. 3. Nominal case tolerance ± 0.02 inches. 4. Nominal pin tolerance ± 0.03 inches. Figure 6. Physical Dimensions. ...