NXP Semiconductors PCA8521
The PCA8521 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.| Part No. | PCA8521 |
|---|---|
| Datasheet | PCA8521 Download |
| Manufacturer |  NXP Semiconductors |
| Description | Infrared remote control transmitter RC5 |
| Buy | Stock & Price |
FEATURES
● RC5 protocol● Maximum of: – 56 keys (20-pin version) – 30 keys (16-pin version).
● Option of multi-system or single system transmitter – Multi-system: maximum 8 systems, selection by key – Single system: maximum 8 different systems per IC, selection by jumper wire or switch.
● Power-down and key wake-up
● High output current (≤ 45 mA)
● Oscillator frequency of 432 kHz or 4 MHz
● Multiple key protection
● Option of 25% or 33% duty factor
● Contained in DIP16, SO16, DIP20 or SO20 packages.
GENERAL DESCRIPTION
PCA8521 However, it does contain a ROM in which the codes that have to be transmitted are stored. An example of an application diagram using a 20-pin IC is illustrated in Fig.7. The oscillator frequency may be optionally chosen as 432 kHz or 4 MHz. For 432 kHz additional external capacitors must be connected. The capacitors for a 4 MHz oscillator is integrated. When a key in the key-matrix is pressed a drive line will be connected to a sense line. This causes the oscillator to start and a corresponding code will be generated conforming to the RC5 protocol.
