HT12A Holtek Semiconductor Inc, HT12A Datasheet
HT12A
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HT12A Summary of contents
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... infrared transmission medium upon receipt of a trigger signal. The capability to select a TE trigger on the HT12E or a DATA trigger on the HT12A further enhances the ap- plication flexibility of the 2 The HT12A additionally provides a 38kHz car- rier for infrared systems. Oscillator ...
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... Block Diagram TE trigger HT12E ¸ ¸ DATA trigger HT12A ¸ ¸ Note: The address data pins are available in various combinations (refer to the address/data table). HT12A/HT12E 2 April 11, 2000 ...
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... These pins can be externally set to VSS or left open Input pins for data D8~D11 setting and transmission en- able, active low These pins should be externally set to VSS or left open (see Note) Encoder data serial transmission output Latch/Momentary transmission format selection pin: Latch: Floating or VDD Momentary: VSS 3 HT12A/HT12E April 11, 2000 ...
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... O OSCILLATOR 2 VSS I ¾ VDD I ¾ Note: D8~D11 are all data input and transmission enable pins of the HT12A transmission enable pin of the HT12E. Approximate internal connections Absolute Maximum Ratings Supply Voltage (HT12A) ..............-0.3V to 5.5V Input Voltage....................V -0 Operating Temperature...............-20°C to 75°C Note: These are stress ratings only. Stresses exceeding the range specified under ² ...
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... No load f =3kHz OSC ¾ V =0.9V (Source =0.1V (Sink ¾ ¾ 0.8V DD ¾ ¾ =1.1MW ¾ OSC V =0V 5V ¾ HT12A/HT12E Ta=25°C Typ. Max. Unit 0 0 200 400 mA 400 800 mA -1.6 ¾ mA 3.2 ¾ ¾ ¾ 0. 150 300 kW Ta=25° ...
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... HT12E or D8~D11 for the HT12A, active low). This cycle will repeat itself as long as the transmission enable (TE or D8~D11) is held low. Once the transmission enable returns high the en- coder output completes its final cycle and then stops as shown below ...
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... An information word consists of 4 periods as illustrated below. Composition of information Address/data waveform Each programmable address/data pin can be externally set to one of the following two logic states as shown below. Address/Data bit waveform for the HT12E Address/Data bit waveform for the HT12A HT12A/HT12E 7 April 11, 2000 ...
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... The status of each address/data pin can be individually pre-set to logic ²high² or ²low² transmis- sion-enable signal is applied, the encoder scans and transmits the status of the 12 bits of ad- dress/data serially in the order A0 to AD11 for the HT12E encoder and A0 to D11 for the HT12A encoder. ...
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... Transmission enable For the HT12E encoders, transmission is enabled by applying a low signal to the TE pin. For the HT12A encoders, transmission is enabled by applying a low signal to one of the data pins D8~D11. Two erroneous HT12E application circuits The HT12E must follow closely the application circuits provided by Holtek (see the ²Application cir- cuits² ...
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... Error: The IC¢s power source is activated by pins AD8~AD11 Flowchart · HT12A ² ² Note: D8~D11 are transmission enables of the HT12A the transmission enable of the HT12E. HT12A/HT12E · HT12E 10 April 11, 2000 ...
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... Oscillator frequency vs supply voltage The recommended oscillator frequency is f HT12A/HT12E (decoder (HT12E encoder) OSCD OSCE (HT12A encoder) OSCE April 11, 2000 ...
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... Application Circuits Note: Typical infrared diode: EL-1L2 (KODENSHI CORP.) Typical RF transmitter: JR-220 (JUWA CORP HT12A/HT12E April 11, 2000 ...
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... Holtek reserves the right to alter its products without prior notification. For the most up-to-date information, please visit our web site at http://www.holtek.com.tw. HT12A/HT12E 13 April 11, 2000 ...