HT62104 HOLTEK [Holtek Semiconductor Inc], HT62104 Datasheet - Page 4

• Manufacturer Part Number: HT62104
• Description: Infrared Remote Encoder
• Manufacturer: HOLTEK [Holtek Semiconductor Inc]

Functional Description
The HT62104 Infrared remote control encoder pro-
vides a means for easy remote control signal encod-
ing. As all functions, including the system oscillator,
are integrated within the device, the addition of exter-
nal switches and an IR LED is all that is required to
implement a full Infrared remote control transmitter
function.
The device will generate an encoded signal on its out-
put pin, DOUT, composed of a Start code, a Custom
code and a Data code. The signal is automatically
generated on the DOUT
K1~K8, changes state from high to low. The internal
pull-high resistors keep these data input pins in a
normally high condition. The output signal on the
DOUT pin can be interfaced to an external IR LED
for wireless signal transmission.
Note: 1.The key data input low signal pulse width must be greater than a 32ms duration for a full signal
Frame Format
There are four frames that the encoder generates for each available sending trigger. The frame code contains three
fields including a 3-bit Start code (110), a 2-bit Custom code (C1, C2) and a 7-bit Data code. Each key data input
corresponds to a specific transmission code shown in the following table.
Frame Code Table
The C1 and C2 pins are internally connected to pull-high resistors whose status are decided by customers.
Connecting to GND represents a “0” while connecting to VDD or keeping in a floating state represents a “1”.
Rev. 1.00
K1 ~ K8
Key
K1
K2
K3
K4
K5
K6
K7
K8
DOUT
2.“Frame” indicates a specific frame code which is determined by the triggering key.
transmission, which consists of a specific repeated frame code, to occur. If the input low signal is less than
or equal to 32ms, then no signal will be transmitted.
S2
1
1
1
1
1
1
1
1
Start Code (S)
S1
1
1
1
1
1
1
1
1
pin when any data input pin,
32 ms
S0
0
0
0
0
0
0
0
0
Custom Code (C)
C1
C1
C1
C1
C1
C1
C1
C1
C1
32 ms < active
C2
C2
C2
C2
C2
C2
C2
C2
C2
4 Frame
4
D6
0
0
0
0
0
0
1
1
Signal Generation
The device will encode and transmit a Start code, a
Custom code and a Data code upon receipt of a trigger
signal. The trigger signal is a high to low transition
on any of the data input pins, K1~K8. The pins are
normally kept at a high level by the internal pull-high
resistors.
Key Input Trigger
The Signal transmission is initiated when any of the
key data input pins changes state from high to low.
If the pulse width of the trigger signal derived from
the key inputs, K1~K8, is less than or equal to 32ms,
there will no signal output on the DOUT pin. If the
pulse width of the trigger signal is greater than 32ms
and less than or equal to 4-frame widths, then a frame
code repeated 4 times, depending upon which key
input is pulled from a high state to a low state, will
be generated on the DOUT pin. If the triggered signal
pulse width is greater than 4-frame widths and less
than or equal to 8-frame widths, then a frame code will
be generated and repeated 8 times on the DOUT pin.
D5
0
0
0
0
0
1
0
0
D4
0
0
0
0
1
0
0
0
4 Frame < active
Data Code (D)
D3
0
0
0
1
0
0
0
0
D2
0
0
1
0
0
0
0
1
8 Frame
May 07, 2012
D1
HT62104
0
1
0
0
0
0
1
1
D0
1
0
0
0
0
0
1
0