HOLTEK HT12F

212 Series of Decoders
Features
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·
·
·
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Operating voltage: 2.4V~12V
Low power and high noise immunity CMOS
technology
Low standby current
Capable of decoding 12 bits of information
12
Pair with Holtek¢s 2 series of encoders
Binary address setting
Received codes are checked 3 times
·
Address/Data number combination
- HT12D: 8 address bits and 4 data bits
- HT12F: 12 address bits only
Built-in oscillator needs only 5% resistor
Valid transmission indicator
Easy interface with an RF or an infrared
transmission medium
Minimal external components
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Car alarm system
Security system
Cordless telephones
Other remote control systems
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Applications
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Burglar alarm system
Smoke and fire alarm system
Garage door controllers
Car door controllers
General Description
12
their local addresses. If no error or unmatched
codes are found, the input data codes are decoded and then transferred to the output pins.
The VT pin also goes high to indicate a valid
transmission.
The 2 decoders are a series of CMOS LSIs for
remote control system applications. They are
12
paired with Holtek¢s 2 series of encoders (refer to the encoder/decoder cross reference tab l e ) . F or p r op er op er a t i on, a p a i r o f
encoder/decoder with the same number of addresses and data format should be chosen.
12
The 2 series of decoders are capable of decoding informations that consist of N bits of address and 12-N bits of data. Of this series, the
HT12D is arranged to provide 8 address bits
and 4 data bits, and HT12F is used to decode 12
bits of address information.
The decoders receive serial addresses and data
12
from a programmed 2 series of encoders that
are transmitted by a carrier using an RF or an
IR transmission medium. They compare the serial input data three times continuously with
Selection Table
Function Address
No.
Part No.
Data
No.
Type
VT
Oscillator
Trigger
Package
HT12D
8
4
L
Ö
RC oscillator DIN active ²Hi² 18 DIP/20 SOP
HT12F
12
0
¾
Ö
RC oscillator DIN active ²Hi² 18 DIP/20 SOP
Notes: Data type: L stands for latch type data output.
VT can be used as a momentary data output.
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July 12, 1999
212 Series of Decoders
Block Diagram
O S C 2
O S C 1
D iv id e r
O s c illa to r
B u ffe r
D IN
D a ta S h ift
R e g is te r
L a tc h C ir c u it
C o m p a ra to r
C o n tr o l L o g ic
D a ta
D a ta D e te c to r
S y n c . D e te c to r
C o m p a ra to r
T r a n s m is s io n G a te C ir c u it
B u ffe r
A d d re s s
V D D
V T
V S S
Note: The address/data pins are available in various combinations (see the address/data table).
Pin Assignment
8 -A d d re s s
4 -D a ta
8 -A d d re s s
4 -D a ta
1 2 -A d d re s s
0 -D a ta
1 2 -A d d re s s
0 -D a ta
N C
1
2 0
N C
N C
1
2 0
N C
A 0
1
1 8
V D D
A 0
2
1 9
V D D
A 0
1
1 8
V D D
A 0
2
1 9
V D D
A 1
2
1 7
V T
A 1
3
1 8
V T
A 1
2
1 7
V T
A 1
3
1 8
V T
A 2
3
1 6
O S C 1
A 2
4
1 7
O S C 1
A 2
3
1 6
O S C 1
A 2
4
1 7
O S C 1
A 3
4
1 5
O S C 2
A 3
5
1 6
O S C 2
A 3
4
1 5
O S C 2
A 3
5
1 6
O S C 2
A 4
5
1 4
D IN
A 4
6
1 5
D IN
A 4
5
1 4
D IN
A 4
6
1 5
D IN
A 5
6
1 3
D 1 1
A 5
7
1 4
D 1 1
A 5
6
1 3
A 1 1
A 5
7
1 4
A 1 1
A 6
7
1 2
D 1 0
A 6
8
1 3
D 1 0
A 6
7
1 2
A 1 0
A 6
8
1 3
A 1 0
A 7
8
1 1
D 9
A 7
9
1 2
D 9
A 7
8
1 1
A 9
A 7
9
1 2
A 9
V S S
9
1 0
D 8
V S S
1 0
1 1
D 8
V S S
9
1 0
A 8
V S S
1 0
1 1
A 8
H T 1 2 D
1 8 D IP
H T 1 2 D
2 0 S O P
H T 1 2 F
1 8 D IP
2
H T 1 2 F
2 0 S O P
July 12, 1999
212 Series of Decoders
Pin Description
Pin Name
I/O
Internal
Connection
Description
NMOS
Input pins for address A0~A11 setting
TRANSMISSION
They can be externally set to VDD or VSS.
GATE
A0~A11
I
D8~D11
O
CMOS OUT
DIN
I
CMOS IN
VT
O
CMOS OUT
OSC1
I
OSCILLATOR
Oscillator input pin
OSC2
O
OSCILLATOR
Oscillator output pin
VSS
I
¾
Negative power supply (GND)
VDD
I
¾
Positive power supply
Output data pins
Serial data input pin
Valid transmission, active high
Approximate internal connection circuits
N M O S
T R A N S M IS S IO N
G A T E
C M O S O U T
C M O S IN
O S C IL L A T O R
E N
O S C 1
O S C 2
Absolute Maximum Ratings
Supply Voltage...............................-0.3V to 13V
Storage Temperature.................-50°C to 125°C
Input Voltage....................VSS-0.3 to VDD+0.3V
Operating Temperature ..............-20°C to 75°C
Note: These are stress ratings only. Stresses exceeding the range specified under ²Absolute Maximum Ratings² may cause substantial damage to the device. Functional operation of this device at other conditions beyond those listed in the specification is not implied and prolonged
exposure to extreme conditions may affect device reliability.
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212 Series of Decoders
Electrical Characteristics
Symbol
Parameter
Ta=25°C
Test Conditions
VDD
Conditions
¾
¾
Min.
Typ.
Max.
Unit
2.4
5
12
V
¾
0.1
1
mA
¾
2
4
mA
VDD
Operating Voltage
ISTB
Standby Current
IDD
Operating Current
5V
No load
fOSC=150kHz
¾
200
400
mA
Data Output Source
Current (D8~D11)
5V
VOH=4.5V
-1
-1.6
¾
mA
Data Output Sink
Current (D8~D11)
5V
VOL=0.5V
1
1.6
¾
mA
VOH=4.5V
-1
-1.6
¾
mA
VOL=0.5V
1
1.6
¾
mA
IO
IVT
VT Output Source Current
VT Output Sink Current
5V
12V
5V
Oscillator stops
VIH
²H² Input Voltage
5V
¾
3.5
¾
5
V
VIL
²L² Input Voltage
5V
¾
0
¾
1
V
fOSC
Oscillator Frequency
5V
¾
150
¾
kHz
ROSC=51kW
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July 12, 1999
212 Series of Decoders
Functional Description
Operation
Flowchart
The 2 series of decoders provides various combinations of addresses and data pins in differ12
ent packages so as to pair with the 2 series of
encoders.
The oscillator is disabled in the standby state
and activated when a logic ²high² signal applies
to the DIN pin. That is to say, the DIN should be
kept low if there is no signal input.
12
The decoders receive data that are transmitted
by an encoder and interpret the first N bits of
code period as addresses and the last 12-N bits
as data, where N is the address code number. A
signal on the DIN pin activates the oscillator
which in turn decodes the incoming address
and data. The decoders will then check the received address three times continuously. If the
received address codes all match the contents of
the decoder¢s local address, the 12-N bits of
data are decoded to activate the output pins
and the VT pin is set high to indicate a valid
transmission. This will last unless the address
code is incorrect or no signal is received.
P o w e r o n
S ta n d b y m o d e
N o
Y e s
A d d r e s s b its
m a tc h e d ?
S to re d a ta
M a tc h
p r e v io u s s to r e d
d a ta ?
Output type
12
Of the 2 series of decoders, the HT12F has no
data output pin but its VT pin can be used as a
momentary data output. The HT12D, on the
other hand, provides 4 latch type data pins
whose data remain unchanged until new data
are received.
8
Latch
2.4V~12V
HT12F
0
12
¾
2.4V~12V
N o
Y e s
N o
3 tim e s
o f c h e c k in g
c o m p le te d ?
Y e s
L a tc h d a ta
to o u tp u t &
a c tiv a te V T
Part Data Address Output Operating
No. Pins Pins
Type
Voltage
4
N o
Y e s
The output of the VT pin is high only when the
transmission is valid. Otherwise it is always
low.
HT12D
D is a b le V T &
ig n o r e th e r e s t o f
th is w o r d
C o d e in ?
N o
A d d re s s o r
d a ta e rro r ?
Y e s
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July 12, 1999
212 Series of Decoders
Decoder timing
E n c o d e r
T r a n s m is s io n
E n a b le
< 1 w o rd
E n c o d e r
D O U T
4 w o rd s
2
1 4
T r a n s m itte d
C o n tin u o u s ly
c lo c k s
4 w o rd s
2
1 4
c lo c k s
D e c o d e r V T
c h e c k
c h e c k
L a tc h e d
D a ta O u t
Encoder/Decoder cross reference table
Package
Decoders
Part No.
Data Pins
HT12D
4
8
Ö
HT12F
0
12
Ö
Address Pins
VT Pair Encoder
Encoder
DIP
SOP
HT12A
18
20
HT12E
18
20
HT12A
18
20
HT12E
18
20
Address/Data sequence
Decoder
DIP
SOP
18
20
18
20
12
The following table provides address/data sequence for various models of the 2 series of decoders. A
correct device should be chosen according to the requirements of the individual addresses and data.
Part No.
Address/Data Bits
0
1
2
3
4
5
6
7
8
9
10
11
HT12D
A0
A1
A2
A3
A4
A5
A6
A7
D8
D9
D10
D11
HT12F
A0
A1
A2
A3
A4
A5
A6
A7
A8
A9
A10
A11
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July 12, 1999
212 Series of Decoders
Oscillator frequency vs supply voltage
fo s c
(S c a le )
R o s c (9 )
4 .0 0
2 7 k
3 .5 0
3 0 k
3 3 k
3 .0 0
3 6 k
3 9 k
4 3 k
2 .5 0
4 7 k
5 1 k
5 6 k
2 .0 0
6 2 k
6 8 k
7 5 k
1 .5 0
8 2 k
1 0 0 k
1 2 0 k
(1 0 0 k H z )1 .0 0
1 5 0 k
1 8 0 k
2 2 0 k
0 .5 0
0 .2 5
2
3
4
5
6
7
8
9
1 0
1 1
1 2
1 3
V D D
(V D C )
The recommended oscillator frequency is fOSCD (decoder) @ 50 fOSCE (HT12E encoder)
1
@ fOSCE (HT12A encoder).
3
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212 Series of Decoders
Application Circuits
R e c e iv e r C ir c u it
1
2
3
4
5
6
7
8
9
A 0
V D D
A 1
V T
A 2
O S C 1
A 3
O S C 2
A 4
D IN
A 5
D 1 1
A 6
D 1 0
A 7
D 9
V S S
D 8
R e c e iv e r C ir c u it
1 8
V D D
1
2
1 7
3
1 6
1 5
R O S C
4
1 4
5
1 3
6
1 2
7
1 1
8
1 0
9
H T 1 2 D
V D D
1 8
A 0
V D D
A 1
V T
A 2
O S C 1
A 3
O S C 2
A 4
D IN
A 5
A 1 1
A 6
A 1 0
1 2
A 7
A 9
1 1
V S S
A 8
1 0
1 7
1 6
1 5
R O S C
1 4
1 3
H T 1 2 F
Notes: Typical infrared receiver: PIC-12043T/PIC-12043S (KODESHI CORP.)
or LTM9052 (LITEON CORP.)
Typical RF receiver: JR-200 (JUWA CORP.)
RE-99 (MING MICROSYSTEM, U.S.A.)
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July 12, 1999
212 Series of Decoders
Holtek Semiconductor Inc. (Headquarters)
No.3 Creation Rd. II, Science-based Industrial Park, Hsinchu, Taiwan, R.O.C.
Tel: 886-3-563-1999
Fax: 886-3-563-1189
Holtek Semiconductor Inc. (Taipei Office)
5F, No.576, Sec.7 Chung Hsiao E. Rd., Taipei, Taiwan, R.O.C.
Tel: 886-2-2782-9635
Fax: 886-2-2782-9636
Fax: 886-2-2782-7128 (International sales hotline)
Holtek Microelectronics Enterprises Ltd.
RM.711, Tower 2, Cheung Sha Wan Plaza, 833 Cheung Sha Wan Rd., Kowloon, Hong Kong
Tel: 852-2-745-8288
Fax: 852-2-742-8657
Copyright ã 1999 by HOLTEK SEMICONDUCTOR INC.
The information appearing in this Data Sheet is believed to be accurate at the time of publication. However, Holtek
assumes no responsibility arising from the use of the specifications described. The applications mentioned herein are
used solely for the purpose of illustration and Holtek makes no warranty or representation that such applications
will be suitable without further modification, nor recommends the use of its products for application that may present a risk to human life due to malfunction or otherwise. 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.
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July 12, 1999