544 communication ics irda infrared communication ic (sir / ask compatible) RPM-800CB series the RPM-800CB series is an infrared communication ic that is compatible with the irda1.0 and ask communication systems. the infrared led, pin photodiode, and modulator circuit are combined onto a single package, and connection to a uart requires just three lines (transmit, receive, and control). applications cellular phones, pagers, pda, phs, notebook pcs, and printers features 1) infrared emitting, receiver, and modulator / demodu- lator on the chip. 2) switchable modes. irda mode ask mode 3) 2.4 to 115.2kbps communication rate. 4) built-in powerdown mode 5) power supply voltage input range 2.7 to 5.5v. absolute maximum ratings (ta = 25 c) recommended operating conditions (ta = 25 c)
545 communication ics RPM-800CB series block diagram pin descriptions
546 communication ics RPM-800CB series input / output circuits
547 communication ics RPM-800CB series electrical characteristics (unless otherwise noted, ta = 25 c and v dd = 3v)
548 communication ics RPM-800CB series circuit operation irda format ask format register function control character format as shown in the fig.3, the control character is made up of four address bits, four data bits, a start bit and a stop bit.
reset 0000 reset 0000 0000 h 0001 m 0010 l reset 0010 0000 2.4kbps 0001 4.8kbps 0010 9.6kbps 0011 19.2kbps 0100 38.4kbps 0101 57.6kbps 0110 115.2kbps (when the clock is 3.6864mhz) reset 0000 0000 irda 0001 ask when v dd = 5v and ask is used, set the led drive control register to m or l. reset 0000 load 0 do not load the baud rate counter value 1 load the baud rate counter value * the load bit automatically returns to 0 after the counter value is loaded. 549 communication ics RPM-800CB series explanation of the registers register table 1) control register 1 echo 0 no control character echo back 1 control character echo back ecan 0 does not cancel reception of transmitted (self emitted) data 1 cancels reception of transmitted (self emitted) data rxen 0 receiver off 1 receiver on txen 0 transmitter off 1 transmitter on 2) led drive current control register 3) baud rate register 4) mode register 5) control register 2
550 communication ics RPM-800CB series timing chart 1) reset operation 2) register write 3) echo back
551 communication ics RPM-800CB series 4) transmit 5) receive 6) echo cancel 7) power down
552 communication ics RPM-800CB series application example operation notes (1) use a shield when there is a possibility of influence due to electromagnetic noise. (2) the baud rate is set to 9600bps after the power is ap- plied, or the ic is reset. (3) the setting in the baud rate register becomes effec- tive when the load bit of control register 2 is set to 1. (4) avoid using together with strong light sources. (5) we recommend to use crystal oscillator.
553 communication ics RPM-800CB series electrical characteristics curves external dimensions (units: mm)
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