HT1612 Holtek Semiconductor, HT1612 Datasheet
HT1612
Related parts for HT1612
HT1612 Summary of contents
Page 1
... Operation current (Typ.) Applications Timers LCD display drivers General Description The HT1612 is a CMOS chip designed for dialer interface which drives digits LCD. Vari- ous functions, such as displaying dialing num- ber and conversation time, are provided. It normally shows blanks. The timer is started to tell users how long the conversation time has been taken when answering a telephone call ...
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... Block Diagram Pad Assignment Chip size: 136 * The IC substrate should be connected to VDD in the PCB layout artwork. 2 134 (mil) 2 HT1612 5th July ’95 ...
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... LCD common signal output pads Hook switch detector input Active low Test pad (connected to VSS for production test) Test pad (connected to VSS for production test) Interrupt output 16Hz by mask option Timer reset and start/hold toggle control input pad 3 HT1612 Unit: mil X Y 61.63 39.46 61.63 47.60 61 ...
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... Negative power supply (GND) Voltage doubler, connected to the external capacitor Voltage doubler, connected to the external capacitor Voltage doubler, connected to the external capacitor Positive power supply No connection Storage Temperature ............... – 125 C +0.3 Operating Temperature ............. – HT1612 5th July ’95 ...
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... VDD) 1.5V No load — 1.5V V =0.3V 500 1000 O 1.5V — 1 1.5V — 2 1.5V — 5 1.5V — — 31.25 1.5V V =0V — IN 1.5V V =1.5V — TIMER 1.5V Crystal=32768Hz — 32768 5 HT1612 =32768Hz, Ta=25 C) Max. Unit 1.5 1.7 V — 0. — 0 — A — — s — — s — — s – — — ...
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... Functional Description Operational flow chart 6 HT1612 5th July ’95 ...
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... Figure b illustrates a timer mode caused by Off-Hook; timer is reset and starts to count the conversation time Figure c. The dialing data are received and displayed on the LCD from left to right after Off-Hook. When the entry interval is over 10 seconds, it resets the timer and starts to count. 7 HT1612 5th July ’95 ...
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... HT1612, the HK pin should be pull-low or keeps low always. Then, the HT1612 is ready to receive the data. At the falling edge of the clock the data are shifted to the IC. After the whole data are sent to the HT1612, the SK pin is set low to avoid switching to the timer mode. 8 HT1612 5th July ’ ...
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... For telephone application The HT1612 is designed to display telephone numbers which are derived from the HT92XXX series telephone dialers. The corresponding data are illustrated in the following table. 9 HT1612 5th July ’95 ...
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... Application Circuits For telephone interfacing The IC substrate should be connected to VDD in the PCB layout artwork. 10 HT1612 5th July ’95 ...
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... For instrument or C use (1.5V supply) The IC substrate should be connected to VDD in the PCB layout artwork. Note drive the SK, DI, and HK pin, an open drain NMOS output structure is recommended drive the SK, DI and HK pin with CMOS output structure, a voltage divider is needed (R=4.3K, R1=10K). 11 HT1612 5th July ’95 ...
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... The IC substrate should be connected to VDD in the PCB layout artwork. Note drive the SK, DI, and HK pin, an open drain NMOS output structure is recommended drive the SK, DI and HK pin with CMOS output structure, a voltage divider is needed (R=20K, R1=10K). 12 HT1612 5th July ’95 ...
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... LCD Connection For 8-digit application Segment Electrode Side LCD driving system 1/2 bias, 1/3 duty, 3V. Common Electrode Side 13 HT1612 5th July ’95 ...
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... LCD Connection For 10-digit application Segment Electrode Side * LCD driving system 1/2 bias, 1/3 duty, 3V. Common Electrode Side 14 HT1612 5th July ’95 ...