Infrarojo

2
Features
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12

HT12A/HT12E Series of Encoders
Minimum transmission word - Four words for the HT12E - One word for the HT12A Built-in oscillator needs only 5% resistor Data code has positive polarity Minimal external components HT12A/E: 18-pin DIP/20-pin SOP package

Operating voltage - 2.4V~5V for the HT12A - 2.4V~12V for the HT12E Low power and high noise immunity CMOStechnology Low standby current: 0.1mA (typ.) at VDD=5V HT12A with a 38kHz carrier for infrared transmission medium

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Applications
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Burglar alarm system Smoke and fire alarm system Garage door controllers Car door controllers

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Car alarm system Security system Cordless telephones Other remote control systems

General Description
The 212 encoders are a series of CMOSLSIs for remote control system applications. They are capable of encoding information which consists of N address bits and 12-N data bits. Each address/data input can be set to one of the two logic states. The programmed addresses/data are transmitted together with the header bits via an RF or an infrared transmission medium upon receipt of a trigger signal. The capability to select a TE triggeron the HT12E or a DATA trigger on the HT12A further enhances the application flexibility of the 212 series of encoders. The HT12A additionally provides a 38kHz carrier for infrared systems.

Selection Table
Function Address Address/ Data Oscillator No. Data No. No. Part No. HT12A HT12E 8 8 0 4 4 0 455kHz resonator RC oscillator Trigger D8~D11 TE Package 18 DIP 20 SOP 18 DIP 20 SOP Carrier Output38kHz No Negative Polarity No No

Note: Address/Data represents pins that can be address or data according to the decoder requirement.

1

April 11, 2000

HT12A/HT12E
Block Diagram
TE trigger HT12E
O S C 2 O S C 1

T E

O s c illa to r

¸ 3 D iv id e r

D a ta S e le c t & B u ffe r S y n c . C ir c u it

D O U T

A 0 1 2 T r a n s m is s io n G a te C ir c u it A 7

¸ 12 C o u n te r & 1 o f 1 2 D e c o d e r

B in a r y D e te c to r

A D 8

A D 1 1

V D D

V S S

DATA trigger HT12A
X 2 X 1

O s c illa to r L /M B A 0 1 2 T r a n s m is s io n G a te C ir c u it A 7

¸ 5 7 6 D iv id e r

D a ta S e le c t & B u ffe r S y n c . C ir c u it

D O U T

¸ 1 2 C o u n te r & 1 o f 1 2 D e c o d e r

B in a r y D e te c to r

D 8

D 1 1V D D

V S S

Note: The address data pins are available in various combinations (refer to the address/data table).

2

April 11, 2000

HT12A/HT12E
Pin Assignment
8 -A d d re s s 4 -D a ta
A 0 A 1 A 2 A 3 A 4 A 5 A 6 A 7 V S S 9 8 7 6 5 4 3 2 1 1 8 1 7 1 6 1 5 1 4 1 3 1 2 1 1 1 0 V D D D O U T X 1 X 2 L /M B D 1 1 D 1 0 D 9 D 8

8 -A d d re s s 4 -D a ta
N C 1 2 3 4 5 6 7 8 9 1 0A 0 A 1 A 2 A 3 A 4 A 5 A 6 A 7 V S S 2 0 1 9 1 8 1 7 1 6 1 5 1 4 1 3 1 2 1 1 N C V D D D O U T X 1 X 2 L /M B D 1 1 D 1 0 D 9 D 8

8 -A d d re s s 4 -A d d r e s s /D a ta

8 -A d d re s s 4 -A d d r e s s /D a ta
N C 1 2 3 4 5 6 7 8 9 1 0 2 0 1 9 1 8 1 7 1 6 1 5 1 4 1 3 1 2 1 1 N C V D D D O U T O S C 1 O S C 2 T E A D 1 1 A D 1 0 A D 9 A D 8

A 0 A 1 A 2 A 3 A 4 A 5 A 6 A 7 V S S 9 8 76 5 4 3 2

1

1 8 1 7 1 6 1 5 1 4 1 3 1 2 1 1 1 0

V D D D O U T O S C 1 O S C 2 T E A D 1 1 A D 1 0 A D 9 A D 8

A 0 A 1 A 2 A 3 A 4 A 5 A 6 A 7 V S S

H T 1 2 A 1 8 D IP

H T 1 2 A 2 0 S O P

H T 1 2 E 1 8 D IP

H T 1 2 E 2 0 S O P

Pin Description
Pin Name I/O Internal Connection CMOS IN Pull-high (HT12A) A0~A7 I NMOS Input pins for address A0~A7 setting TRANSMISSION Thesepins can be externally set to VSS or left open GATE PROTECTION DIODE (HT12E) NMOS TRANSMISSION Input pins for address/data AD8~AD11 setting GATE PROTECTION These pins can be externally set to VSS or left open DIODE (HT12E) CMOS IN Pull-high CMOS OUT CMOS IN Pull-high Input pins for data D8~D11 setting and transmission enable, active low These pins should be externally set to VSS or left open (see...