### Overview of the TSOP772..W Series The **TSOP772..W** series consists of miniaturized IR receiver modules designed for infrared remote control systems. These devices integrate a photo detector and a preamplifier into a single lead frame, encapsulated in an epoxy package that acts as an IR filter. --- ### Key Technical Specifications The following table summarizes the primary electrical and physical characteristics of the TSOP772..W components: | Parameter | Value / Range | | :--- | :--- | | **Supply Voltage ($V_S$)** | 2.5 V to 5.5 V | | **Supply Current ($I_S$)** | 0.7 mA (typical) | | **Carrier Frequency ($f_o$)** | 30 kHz to 56 kHz (model dependent) | | **Transmission Distance** | Up to 45 meters | | **Directivity** | $\pm$ 45 degrees | | **Output Type** | Active Low | --- ### Internal Block Diagram Functions The device contains several critical electronic sub-circuits to ensure reliable signal processing: 1. **Photo Diode:** Converts incoming infrared light into an electrical signal. 2. **Preamplifier:** Amplifies the weak signal from the photo diode. 3. **Automatic Gain Control (AGC):** Adjusts sensitivity to suppress noise from ambient light (like sunlight or fluorescent bulbs). 4. **Band Pass Filter:** Specifically tuned to the carrier frequency (e.g., 38 kHz) to reject interference. 5. **Demodulator:** Removes the carrier frequency and sends the data pulses to the output pin. --- ### Pin Configuration The TSOP772..W typically uses a 3-pin layout: | Pin Number | Symbol | Function | | :--- | :--- | :--- | | 1 | **OUT** | Data Output (connects to MCU) | | 2 | **GND** | Ground | | 3 | **$V_S$** | Power Supply | --- ### Application Design Circuit To ensure stable operation, a basic RC filter is recommended on the supply line to suppress power ripples. ```cpp // Schematic representation [ V_S (5V) ]----[ R1: 100 Ohm ]----+----[ Pin 3: Vs ] | [ C1: 4.7 uF ] | [ GND ]----------------------------+----[ Pin 2: GND ] [ MCU Input ]---------------------------[ Pin 1: OUT ] ``` --- ### Distinction: The "W" Suffix The **"W"** in the part number indicates **Wideband** or improved immunity against noise. These versions are specifically designed to handle disturbances from energy-saving lamps (CFLs) and modern LCD backlighting, which often emit infrared interference.