SC8521 Datasheet, PDF (1/16 Pages) Silan Microelectronics Joint-stock – INFRARED REMOTE CONTROL TRANSMITTER RC5

Silan
Semiconductors
SC8521
INFRARED REMOTE CONTROL
TRANSMITTER RC5
DESCRIPTION
The SC8521 can be used in infrared remote control
transmitters. It generates output pulses, in accordance with the RC5
protocol, when a key is pressed. The IC does not contain a software
programmable processor. However, it does contain a ROM in which
the codes that have to be transmitted are stored. The oscillator
frequency may be optionally chosen as 432KHz. For 432KHz
additional external capacitors must be connected. When a key in the
key-matrix is pressed a driveline will be connected to a sense line.
This causes the oscillator to start and a corresponding code will be
SOP-20
generated conforming to the RC5 protocol.
Seven drive lines ( DR0 to DR6 ) and eight sense lines (SN0
to SN7) may be connected via the key matrix to scan the keys.
When two or more keys are activated simultaneously no ^{∗ Power-down and key wake-up}
transmission will take place.
∗ High output current (≤45mA)
∗ Oscillator frequency of 432KHz
FEATURES
∗ Multiple key protection
∗ RC5 protocol
∗ Option of 25% or 33% duty factor
∗ Maximum of 56 keys (20-pin version)
∗ Option of multi-system or single system transmitter
ORDERING INFORMATION
-- Multi-system: maximum 8 system, selection by key
SC8521
SOP-20 Package
-- Single system: maximum 8 different systems per IC, selection
by jumper wire or switch.
PIN CONFIGURATIONS
XTAL1 1
XTAL2 2
SN7 3
SN0 4
SN1 5
SN2 6
SN3 7
SN6 8
SN4 9
SN5 10
20 VDD
19 Lout
18 VSS
17 DR6
16 DR0
15 DR1
14 DR2
13 DR3
12 DR4
11 DR5
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
REV: 1.3
1
2002.03.01