HT6026 Remote Control Encoder Features • • • • • • • Operating voltage: 4V~18V Low standby current Low power and high noise immunity CMOS technology 39 difference codes • Two transmission words minimum Built-in oscillator needs only 5% resistor Interface with RF or infrared transmission medium Minimal external components • • • Security system Cordless telephones Other remote control systems Applications • • • • Burglar alarm system Smoke and fire alarm system Garage door controllers Car alarm system General Description The HT6026 is a CMOS LSI encoder designed for use in remote control system. It is capable of encoding 9 bits of information which consists of N address bits and 9–N data bits. Each address/data input is externally trinary programmable by external switches. The programmable address/data is transmitted along with the header bits via an RF or an infrared transmission medium upon receipt of a trigger signal (TE). Pin Assignment Block Diagram The HT6026 is pin compatible with the MC145026. 1 2nd Oct ’97 HT6026 Pad Coordinates Unit: µm Pad No. X Y Pad No. X Y 1 –598.00 689.00 9 160.00 –687.00 2 –674.00 433.00 10 670.00 –687.00 3 –674.00 126.00 11 670.00 –347.00 4 –674.00 –162.00 12 670.00 172.00 5 –674.00 –449.00 13 670.50 689.50 6 –598.00 –687.00 14 270.00 689.00 7 –342.00 –687.00 15 –84.00 689.00 8 –127.00 –687.00 16 –299.00 689.00 2 Chip size: 1650 × 1680 (µm) * The IC substrate should be connected to VSS in the PCB layout artwork. Pin Description Pin Name I/O Internal Connection Description 1~7 AD0~AD6 I TRANSMISSION GATE Input pins for address/data AD0~AD6 setting They can be externally set to VDD, VSS, or left open 8 VSS I — 9~10 AD7~AD8 I TRANSMISSION GATE 11 OSC1 I OSCILLATOR Oscillator input pin 12 OSC2 O OSCILLATOR Oscillator output pin 13 OSC3 O OSCILLATOR Oscillator output pin 14 TE I CMOS IN Pull-High 15 DOUT O CMOS OUT 16 VDD Pin No. Negative power supply (GND) Input pins for address/data AD7~AD8 setting They can be externally set to VDD, VSS, or left open Transmission enable, active low Encoder data serial transmission output — Positive power supply 2 2nd Oct ’97 HT6026 Approximate internal connection circuits Absolute Maximum Ratings* Supply Voltage ............................... –0.3V to 24V Storage Temperature................. –50°C to 125°C Input Voltage.................... VSS–0.3 to VDD+0.3V Operating Temperature............... –20°C to 75°C *Note: Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only. Functional operation of this device at these or any other conditions above those indicated in the operational sections of this specification is not implied and exposure to absolute maximum rating conditions for extened periods may affect device reliability. (Ta=25°C) Electrical Characteristics Symbol Parameter VDD Operating Voltage ISTB Standby Current IDD Operating Current Test Conditions VDD Conditions — — 5V 15V 5V Output Drive Current No load, FOSC=18kHz 15V No load, FOSC=22kHz 5V IDOUT Oscillator stops 15V 5V 15V VOH=0.9VDD (Source) VOL=0.1VDD (Sink) Min. Typ. Max. Unit 4 — 18 V — 0.1 0.3 µA — 0.1 0.5 µA — 500 900 µA — 2000 3000 µA –1.0 –1.7 — mA –8.0 –14.0 — mA 0.8 1.5 — mA 5.0 10.0 — mA VIH “H” Input Voltage — — 0.7VDD — VDD V VIL “L” Input Voltage — — 0 — 0.3VDD V RTE TE Pull-High Resistance — 800 — kΩ — 250 — kΩ — 18 — kHz FOSC Oscillator Frequency — 22 — kHz 5V 15V VTE=0V REXT=10kΩ CEXT=2000PF 15V RS=20kΩ 5V 3 2nd Oct ’97 HT6026 Functional Description Operation The HT6026 encoder begins a one-word transmission cycle upon receipt of a transmission enable (TE, active low). This cycle will repeat itself as long as the transmission enable (TE ) is held low. Once the transmission enable returns high, the encoder output completes its final N×2 word cycle, and then stops as shown in Figure 1. The total number of transmission cycles allowed is always adjusted to an even number automatically. Figure 1. Transmission timing Information word An information word consists of 2 periods as shown: Figure 2. Composition of information Address/data waveform Each programmable address/data pin can be externally set to one of the following three logic states: Figure 3. Address/Data bit waveform 4 2nd Oct ’97 HT6026 The address pins are usually pre-set to transmit data codes with their own particular security codes by the DIP switches or PCB wiring, while the data is selected by the push button or electronic switches. Address/data programming (preset) The status of each address/data pin can be individually pre-set to logic “high”, “low”, or “floating”. If a transmission enable signal is applied, the encoder scans and transmits the status of 9-bit address/data serially in the order AD0 to AD8. But if the trigger signal is not applied, the chip only consumes a standby current which is less than 1µA (for VDD=5V). The following figure demonstrates an application using the HT6026: The transmitted information is as listed: Pilot & Sync. AD0 AD1 AD2 AD3 AD4 AD5 AD6 AD7 AD8 1 Z 1 Z Z Z 0 1 Z Z: floating 5 2nd Oct ’97 HT6026 Transmission enable Transmission is enabled by applying a low signal to the TE pin. The HT6026 is enabled and outputs address/data codes from DOUT pin when the TE is set to “low” and more than 65ns. Flowchart Oscillator frequency vs supply voltage 6 2nd Oct ’97 HT6026 Application Circuit Note: Typical infrared diode: EL-1L2 (KODENSHI CORP.) Typical RF transmitter: JR-220 (JUWA CORP.) 7 2nd Oct ’97