LC7461

Infrared Remote Control Transmitter IC Functions . 32%3 function keys . 13-bit custom codes . Operating supply voltage range VDD = 1.8 to 3.6 V . Supply current at the standby mode IDD = 1 µA or less . Double-press operation keys (no priority given) . On-chip oscillator (ceramic resonator : connected externally) Features . The custom code consists of 7 bits to be fixed by the on-chip ROM and 6 bits being pin-settable. Sixty-four custom codes may be selected externally (no diode required). . Minimum number of external parts required Package Dimensions unit : mm 3045B-MFP24 [LC7461M] SANYO : MFP24 Specifications Absolute Maximum Ratings at Ta = 25°C Parameter Symbol Conditions Ratings Unit Maximum supply voltage VDD max VDD VSS–0.3 to +5.5 V Input voltage VIN Each input pin VSS–0.3 to VDD+0.3 V Output voltage VOUT Each output pin VSS–0.3 to VDD+0.3 V Output current IOUT OUT –35 mA Allowable power dissipation Pd max Ta % 85°C 150 mW Operating temperature Topr –40 to +85 °C Storage temperature Tstg –50 to +125 °C Allowable Operating Conditions at Ta = 25°C Parameter Symbol Pin Name Conditions min typ max Unit Supply voltage VDD VDD fOSC = 455 kHz 1.8 3.0 3.6 V Input high-level voltage VIH KI0 to KI3, C0 to C5 0.7 VDD VDD V Input low-level voltage VIL KI0 to KI3, C0 to C5 VSS 0.3VDD V Oscillation frequency fOSC 400 455 500 kHz Ordering number: EN2119D CMOS LSI LC7461M SANYO Electric Co.,Ltd. Semiconductor Bussiness Headquarters TOKYO OFFICE Tokyo Bldg., 1-10, 1 Chome, Ueno, Taito-ku, TOKYO, 110 JAPAN O3096HA(II)/7058YT/6036KI,TS(KOTO) No.2119-1/7 Electrical Characteristics at Ta = 25°C, VDD = 3.0 V Parameter Symbol Pin Name Conditions min typ max Unit Operating supply current IDD VDD Key ON, output: no load 1 mA Quiescent supply current IDS VDD All keys OFF, OSC stop 1 µA Output high-level current IOH1 OUT VDD = 1.8 V, VOH = 1.0 V –8 mA IOH2 OUT VDD = 3.0 V, VOH = 1.0 V –25 mA Output high-level voltage VOH KO0 to KO7 IOH = –0.1 mA 0.3 V Output low-level voltage VOL OUT IOL = 0.1 mA 0.3 V Output OFF-state leakage current IOFF KO0 to KO7 1 µA Input high-level current IIH C0 to C5 VIN = VDD 1 µA Input low-level current IIL C0 to C5 VIN = VSS –1 µA Input floating voltage VIF KI0 to KI3 0.1 VDD V Input pull down resistance RIN KI0 to KI3 75 100 125 kΩ Internal Block Diagram Key output timing signal generator Output circuit Oscillator Divider Decoder Key entry circuit Key data register Custom code register LC7461M No.2119-2/7 Pin Assignment Top view Pin Description Pin Name Pin No. Input/Output Internal Equivalent Circuit Pin Function VDD, VSS 8, 12 Power supply pins VSS = GND KO0 to KO7 13 to 20 Output Key scan timing signal output pins KI0 to KI3 1 to 4 Input Keys return signal entry pins OSC1 OSC2 10 11 Input/output Input/output pins for ceramic resonator-used oscillation Oscillator configuration C0 to C5 21 to 24, 5, 6 Input Input pins for custom code setting Capable of externally setting 6 bits of 13 bits in all that provide a custom code OUT 7 Output Output pin for transmit LED drive TEST 9 Input LSI test pin Normally set to high-level or brought to open state LC7461M No.2119-3/7 General Description of Function 1. Oscillator Since a self-bias type amplifier of CMOS inverter is contained, an oscillator can be formed by connecting a ceramic resonator. To minimize power dissipation, the oscillator stops oscillating except when key operation is performed. 2. Key entry Key entry pins KI0 to KI3 and timing signal output pins KO0 to KO7 provide a key matrix of 4 × 8 = 32. Multi-press of key No. 20 and one of key No. 21, 22, 23 may be done, with no priority given in key entry. When the two keys are kept pressed, a series of pulses will be output according to each key entry. If multi-press of keys which are not allowed multi-press is done, no output will be delivered. 3. Data organization Data consists of 42 bits in all: 13 bits of custom code, 8 bits of key data, and their inverted codes. Custom code Custom code Key data Key data 13 bits 13 bits 8 bits 8 bits LC7461M No.2119-4/7 (a) Custom code The custom code, which consists of 13 bits (C0 to C12) in all, is used to distinguish between receiving sets. C6 to C12 are fixed by the mask ROM and C0 to C5 are pin-settable. The custom codes are controlled by Sanyo to avoid duplication. (b) Key data When multi-press of key No.20 and one of key No.21, 22, 23 is done, multi-bit D5 will be set to ‘‘1’’, with no priority given in key entry. Pin-selectable Mask ROM 6 bits 7 bits In this example C0 to C5 are set as follows: C0 C1 C2 C3 C4 C5 0 1 1 0 0 1 Multi-press KEY No. D0 D1 D2 D3 D4 D5 D6 D7 20, 21 1 0 1 0 1 1 0 0 20, 22 0 1 1 0 1 1 0 0 20, 23 1 1 1 0 1 1 0 0 . D6, D7 may be preset to ‘‘0’’,‘‘1’’ beforehand (mask option). KEY No. D0 D1 D2 D3 D4 D5 D6 D7 0 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0 2 0 1 0 0 0 0 0 0 3 1 1 0 0 0 0 0 0 4 0 0 1 0 0 0 0 0 5 . . . 28 1 . . . 0 0 . . . 0 1 . . . 1 0 . . . 1 0 . . . 1 0 . . . 0 0 . . . 0 0 . . . 0 29 1 0 1 1 1 0 0 0 30 0 1 1 1 1 0 0 0 31 1 1 1 1 1 0 0 0 (H: Key-ON state) Key 20 data transmit Keys 20, 21 multi-press data transmit Key 21 data transmit Transmit stop Key 22 data transmit Keys 20, 22 multi-press data transmit LC7461M No.2119-5/7 4. Transmit waveforms The period of time shown below is for fOSC = 455 kHz. Custom code Custom code Key data Key data 13 bits 13 bits 8 bits 8 bits Leader code . First time . Second time onward (Transmission is available only when key entry continues.) . Carrier waveform Carrier frequency = 1/12 fOSC 7 38 kHz LC7461M No.2119-6/7 Sample Application Circuit In this example custom code C0 to C5 is C0 z z z z z C5. 0 1 0 1 0 1 No products described or contained herein are intended for use in surgical implants, life-support systems, aerospace equipment, nuclear power control systems, vehicles, disaster/crime-prevention equipment and the like, the failure of which may directly or indirectly cause injury, death or property loss. Anyone purchasing any products described or contained herein for an above-mentioned use shall: 1 Accept full responsibility and indemnify and defend SANYO ELECTRIC CO., LTD., its affiliates, subsidiaries and distributors and all their officers and employees, jointly and severally, against any and all claims and litigation and all damages, cost and expenses associated with such use: 2 Not impose any responsibility for any fault or negligence which may be cited in any such claim or litigation on SANYO ELECTRIC CO., LTD., its affiliates, subsidiaries and distributors or any of their officers and employees jointly or severally. Information (including circuit diagrams and circuit parameters) herein is for example only; it is not guaranteed for volume production. SANYO believes information herein is accurate and reliable, but no guarantees are made or implied regarding its use or any infringements of intellectual property rights or other rights of third parties. This catalog provides information as of October, 1996. Specifications and information herein are subject to change without notice. Transmit LED LC7461M No.2119-7/7