cf8223a Nippon Precision Circuits Inc, (NPC), cf8223a Datasheet
cf8223a
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cf8223a Summary of contents
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... OVERVIEW The CF8223A is a FSK (Frequency shift keying) decoder and DTMF (Dual tone multi-frequency) receiver IC fabricated using a CMOS process and features a power-down function for low power dissipation opera- tion. The FSK decoder and DTMF receiver have the same performance characteristics as dedicated ICs that perform the same functions, with the added benefi ...
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... DOUT Ol down state Data trigger output. Data is output on DOUT when this pin goes LOW. 16 VDD – Supply 1. Shimitt trigger input CF8223A FSK/DTMF FSK Decoder Band Pass Filter High Group Filter Dial Tone Filter Low Group Filter DTMF Receiver OSC Ring Detect ...
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... PDWN, RDIN, RDRC HIGH-level input voltage OSCIN LOW-level input voltage OSCIN HIGH-level input voltage DOUT, DV, RDET, FSK/DTMF LOW-level output current DOUT, DV, RDET, FSK/DTMF HIGH-level output current PDWN, RDIN input leakage current RDRC output leakage current CF8223A Symbol stg ...
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... GND = 0V Parameter Input leakage current Input resistance DC open-loop voltage gain Unity gain frequency Load capacitance Load resistance CF8223A = − ° C unless otherwise noted. = 3.579545MHz, T CLK a Symbol Condition Typical application circuit Mark signal and SPACE signal are same level. ...
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... Signal detection time Received signal non-detection time Pause detection time Pause non-detection time DV output data delay time Power-down release time Oscillator start-up time DOUT data rate DTMF flag setup time CF8223A = − ° C unless otherwise noted. a Symbol Condition ...
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... OSCIN input timing (when external input OSCIN V SS FSK receive timing (1) 1st Ring Tip/Ring RDET DV FSK/DTMF DOUT PDWN OSCOUT FSK receive timing ( Tip/Ring DOUT CF8223A Ch. seizure Mark Data packet 1010101... 111... Data t DED ADD Data t ...
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... DTMF receive timing (1) Tip/Ring DTMF Data # FSK/DTMF DOUT t DPD PDWN t DOSC OSCOUT DTMF receive timing (2) DV DOUT (FSK/DTMF) DOUT output timing DOUT CF8223A BDD Data #1 t BDD DTMF data Checksum Start bit ...
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... R and R (point b), and then 1 2 input on RDIN. When the ring signal input on RDIN exceeds the Schmitt buffer trigger voltage (0.7V the output switches the open-drain RDRC pin. The signal at RDRC (point c) drives a time-constant cir- CF8223A RDIN R4 R1 RDRC ...
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... V DD In ------------------------- - V – V where t is the guard time, and the trigger level satis- ≤ V ≤ 0.7V fies the expression 0. CF8223A Point a Signal Point b Signal Point c Signal Point d Signal . DD NIPPON PRECISION CIRCUITS INC.—9 V RIG 0. RIG 0. ...
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... Input Differential Amplifier The CF8223A uses an input differential amplifier for input gain adjustment of the tip/ring signal input to the FSK detector or DTMF receiver. Differential input configuration and single-ended input configu TIP C1 R1 RING AGND C The gain for single-ended configurations is given by the following equation ...
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... The DTMF receiver demodulates the received DTMF signal and outputs data bits Q bit (2-mod-16) checksum DOUT. CF8223A Table 1. FSK signal Parameter Modulation type Logic “1” data (mark) Logic “0” data (space) Signal level (mark) Signal level (space) ...
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... Start bit (LSB first) Figure 5. DTMF signal to DOUT output wait state (see timing diagrams in AC Electrical Characteristics). The CF8223A DTMF receiver can be used as a general-purpose DTMF receiver without the need for the external time constant circuit, in ≥ 20ms, a data which case the resistor/capacitor/diode network can be omitted ...
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... 270 470 4 D 1N4004 – X’tal 3.579545 1. Refer to the Input Differential Amplifier. 2. Refer to the Ring Signal Detector. CF8223A D1 R2 TIP D1 RING AGND RDIN D1 RDRC D1 RDET PDWN Unit kΩ ...
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... Customers are requested not to export or re-export, directly or indirectly, the Products to any country or any entity not in compliance with or in violation of the national export administration laws, treaties, orders and regulations. Customers are requested appropriately take steps to obtain required permissions or approvals from appropriate government agencies. CF8223A NIPPON PRECISION CIRCUITS INC. 4-3, Fukuzumi 2-chome, Koto-ku, ...