PCA8521BT PHILIPS [NXP Semiconductors], PCA8521BT Datasheet - Page 8

• Manufacturer Part Number: PCA8521BT
• Description: Infrared remote control transmitter RC5
• Manufacturer: PHILIPS [NXP Semiconductors]

Philips Semiconductors
Table 3 ROM bit description
Pulse output
The bits of the remote control word, as indicated by the addressed ROM locations, are loaded into a shift register every
bit-time this register is shifted. The output is used to generate a logic 0 or a logic 1 in the biphase (Manchester) coding,
modulated with a frequency of 36 kHz. The duty factor of the modulation pulses may be selected (optionally) to be 25%
or 33.3%. The output of the pulse generator controls the output driver that can provide a maximum current of 45 mA.
1999 Jun 15
handbook, full pagewidth
Infrared remote control transmitter RC5
M0H to M4H
M5H to M7H
M0L to M5L
end control
BITS
M6L
M7L
start input
no key
432 kHz
4 MHz
or
Command bits 0 to 5.
Field bit. This bit indicates whether command codes 0 to 63 are used (field bit is at logic 1) or
command codes 64 to 127 are used (field bit is at logic 0).
Inhibit bit. When this bit is at logic 1 no transmission will take place. When this bit is at logic 0
the appropriate code-word will be transmitted.
System bits 0 to 4.
Bank select. Will be stored in BS0 to BS2 when the ‘multi-system’ option is selected. With
single system bits M5H to M7H are don't care.
OSCILLATOR
S
CLK
R
CLR
STOP
Q
Q
Fig.4 Timer schematic diagram.
CLK1
432 kHz
4 MHz
8
DIVIDE BY 111
DIVIDE BY 12
FUNCTION
CLK2
DIVIDE-BY-4096
INV
CONTROL
Product specification
MBH035
TIMER
PCA8521
pulse
C0
C11