SDA2208-3 SIEMENS | Alldatasheet
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IR Remote Control Transmitter with IR Diode Driver SDA 2208-3 Preliminary Data Bipolar IC The SDA 2208-3 is designed as a remote control transmitter for direct driving of infrared transmitter diodes. The instructions are generated by an input matrix (i. e. keyboard) in the form of biphase codes. Distributed over 8 levels, there are a max. of 512 instructions available. The newly designed SDA 2208-3 is feature compatible with the pins and functions of the SDA 2208-2. The SDA 2208-3 is much better protected against electro- static discharges (ESD). Type Ordering Code Package SDA 2208-3 Q67000-A8235 P-DIP-20 Circuit Description Voltage Supply Voltage consumption ceases in the quiescent state and is activated subsequent to connecting the component's matrix. When the matrix is disconnected, the IC automatically completes the telegram and returns into the quiescent state. Clock Input The clock input is equipped with a ceramic resonator. This resonator oscillates with its parallel resonance. In addition, the clock signal can be injected at pin CLK I. The oscillator can be also operated by using an LC circuit with an isolating capacitor. Input Matrix The matrix is comprised of 8 rows and 8 columns. Column A is used as supply voltage Vs. In order to transmit a telegram, the respective rows and columns have to be connected. The transmitter is switched on and a telegram is output. The length of the telegram depends on the duration of the matrix connection. A telegram is comprised of a start command, a variable number of information commands (depending on the duration of the matrix connection). 97 01.90
The programming pin is used to provide access to all command sets or 512 commands ‘since the 8 x 8 matrix limits the use to one command set or 64 different commands. By subdividing the command sets into 8 levels of 64 commands each, a specific level can be selected by either keeping the PPIN open or by combining it with one of the seven column inputs (CPB to CPH). When connecting PPIN with one column alone, the standby supply current /s does not increase Safety Features against Incorrect Operation As a prerequisite for an error-free telegram output with at least one information command, the matrix connection has to be free of interferences and its clock-frequency-dependent, minimal duration should be approx. 60 ms at a clock frequency of 500 kHz. The applied integrated circuit is equipped with a preventive mechanism (key bouncing) against erroneous outputs, which automatically resets the circuit during each detected interference. Equally, operating errors caused by connecting more than one row and one column are detected. The telegram will be ended through continuous transmitting of end. Operating errors can be cancelled only by disconnecting all matrix connections. The level selection key (PPIN function) will be effective only if it is depressed prior to or simultaneously with the matrix key. Also, a simultaneous depressing of several selection keys has the same effect on the telegram as an erroneous matrix operation. Composition of a Telegram Subsequent to switch-on, the command No. 511 (10-bit word length) is output as start command to indicate to the receiver the onset of transmission. Depending on the duration of the matrix connection, a series of identical commands will follow. If a telegram is ended by disconnecting the matrix connection, not more than one additional information command will be issued to be followed immediately by the end command. This end command is identical with the start command. Command Structure Each command consists of a presignal, an infrared pause, a start bit and 9 information bits. During the duration of the presignal (256/f.x), the receiver performs a simple amplitude adjustment of the input amplifier. The infrared pause appears between the end of the presignal and the onset of the start bit. Again, the receiver is provided with enough time to recognize transmission distortions based on the limits of the transmission range. The start bit has been permanently programmed as "1" and is used as synchronization ‘support for the receiver. The bit structure has been illustrated in the pulse diagram. Output Driver Stage The fully integrated driver stage enables the direct connection of the infrared transmitter diodes to the infrared output IRA. The diode current is maintained at a constant level within a defined range to stabilize the transmitting power of the infrared diodes. Siemens Aktiengeselischaft 98
Pin Configuration = (top view) eno []1 20] ciKxi ra []2 191) cr % 03 ref] co rz [fe v1] ce e7s wl] ce ri (fe sf] ce ro []7 ut ce re [Is af] cn re [9 121] erin 3 []0 up] es weve Pin Definitions and Functions PinNo. [Symbol —_| Function
1 GND Ground
“2 (IRA Output IRA _ 3. | Vs Supply voltage i — 4 | es 8 [| 8 [re 10 R3
11 RS 2
12 PPIN | ProgrammingPin
13 [CH _ en 16 [cc ‘| _F Matrix connection column a 18 joo 19 CF Siemens Aktiengeselischaft 99
Ta= 25°C Parameter Symbol Limit Values | Unit Supply voitage range ac -0.3 to 10.5 v Matrix rows | Veow = 0.3 to Vs v Matrix columns Veo v Programming pin (PPIN) =0.3to Vs v Oscillator input (CLK) =0.3 102 v Infrared output (IRA) inhibited Vo —0.3to 10.5 Vv in operation Ve -0.3to8 v Junction temperature iT 150 c rong tera rage Zz a Thermal resistance Ransa KW (system-air) : Operating Range Supply voltage lve [ator |v Ambient temperature Ta Oto 70 c Oscillator frequency | foux 430 to 530 kHz Characteristics Vs=5.5V; Ta = 25°C Parameter Symbol Limit Values Unit min. typ. max. | Current consumption | transmitting phase Is | 19 mA standby operation Is | <1 10 nA Output current IRA. Ie mA 2V<ve<6V Connecting resistance R row col a (row-column or column-PPIN) Siemens Aktiengeselischaft 100
=i b J alc q e ues for 500 kHz b = 60.928 ms c = 26.624 ms d = 177.664 a) bounce b) minimum key operating time to complete telegram with one information instruction c) delay between the on-set of error-free matrix connection and on-set of telegram d) telegram with one information command e) telegram with several identical information commands Composition of Telegram “ye d- - . et ve 1260 for 500 kHz a=c=f=13.312ms b = 19.968 ms d=e=177.76 ms a) start command 10 bits . b) time interval between start and information command c) information command 10 bits ) time interval between identical information commands e) time interval between information and end command f) end command 10 bits The timespan of an error-free matrix connection determines the number of identical infor- mation commands. Siemens Aktiengeselischaft 101
Command Structure in Biphase Code Ir folrtrfolotrlolofsol Infra Weinert S ALB LCIDLETFIGIAITI vena Time duration _ single bit e: 512/foux presignal V: 256/foux infrared pause: 5 x 256/fc.x start bit S is always 1 bits A to | are addressable Structure of the Modulated Half Bit (as well as the presignal) Ba Le aly one og __J vena a=c=4lfax b= 16/fax d = 256/foux 16 pulses per half bit The H signal indicates a constant current source at Q is. The infrared transmitter diode is then active. Siemens Aktiengesellschaft 102
se [v= CA I a TTTTTT sl, vs ETT ule ¥% TLL le ke G IRA Teh 13h cy Set Sooo ooh tle, 0 SoG GGG lp; osc x SoG ea oo Hh tiles SoBe EEGS io, HSER GG slo, = SSEREoGG sles TrTTTTTT 1 0 —— Matrix Connecti ms [Performed with Keys un Since the infrared transmitter diodes have to be driven with pulse currents of approx. 1 A, the following has to be complied with during the layout of the PC board: 1) The smoothing capacitor between Vs and ground should be located as closely as possible to the pins of the IC. 2) The supply line to the transmitter diodes is not to cause cross-talk in the key matrix. 3) No residual currents are to flow over the connection ceramic oscillator/ground pin. Siemens Aktiengesellschaft 103
No. of the | Matrix Binary code instruction | connection IRA information instruction row-column ABCDEFGHI 0 1A oo0oo0000000 1 1B 100000000 2 1c 010000000 3 1D 110000000 4 1E 001000000 5 1F 101000000 6 1G 011000000 7 1H 111000000 8 2A oo00100000 9 2B 100100000 10 2c 010100000 W 2D 110100000 12 2E oo1100000 13 oF 101100000 14 2G o11100000 15 2H 111100000 16 3A 000010000 17 3B 100010000 18 3c 010010000 19 3D 110010000 20 3E 001010000 21 3F 101010000 22 3G 011010000 23 3H 111010000 24 4A 000110000 25 4B 100110000 26 4c 010110000 27 4D 110110000 28 4E 001110000 29 4F 101110000 30 4G 011110000 31 4H 111110000 32 5A 000001000 33 5B 100001000 34 5C 010001000 35 5D 110001000 36 5E oo1001000 37 5F 101001000 38 5G 011001000 39 5H 111001000 40 6A oo0oo0101000 Siemens Aktiengeselischaft 104
Truth Table (cont'd) No. of the Matrix Binary code instruction connection IRA information instruction row-column ABCDEFGHI 41 6B 100101000 42 6c 010101000 43 6D 110101000 44 6E 001101000 45 6F 101101000 46 6G 011101000 47 6H 111101000 48 7A 000011000 49 7B 100011000 50 7c 010011000 51 7D 110011000 52 7E 001011000 53 7F 101011000 54 7G }011011000 55 7H 111011000 56 8A 000111000 57 8B 100111000 58 8c 010111000 59 8D 110111000 60 8E oo1111000 61 8F |101111000 62 8G (011111000 63 8H | 111111000 GHt Command Oto 63: PPIN free 000 Command 64 to 127: PPIN connected with CB 100 Command 128 to 191: PPIN connected with CC 010 Command 192 to 255: PPIN connected with CD 110 Command 256 to 319: PPIN connected with CE oo1 Command 320 to 383: PPIN connected with CF 101 Command 384 to 447: PPIN connected with CG. o11 Command 448 to 511: PPIN connected with CH 144 In every command set, the assignment instruction — matrix connection (row — column) is analogous to the group 0 to 63. Example: Command 64 is generated, when PPIN is connected with CB, and R1 with CA. Siemens Aktiengesellschatt 105