1. General Description & Function

️· The TH7202 is an ASK (Amplitude Shift Keying) Transmitter designed for 315 MHz operation.
️· It appears to be intended for wireless communication applications.

2. Electrical Characteristics - Supply & Currents

️· Supply Voltage (Vcc): The datasheet doesn't explicitly state a maximum but implies operation within a range up to around 6V, likely based on the graphs.
️· Supply Current: Graphs (Figures 5-10) show supply current versus Vcc for different power steps (0-4) and at different temperatures (125°C, 85°C, 25°C, -20°C, -40°C). This is crucial for power budget calculations.
- Standby Current (Power Step 0): Varies with temperature, from ~5.5µA at 125°C to ~3.0µA at -40°C.
- Power Steps 1-4: Show progressively higher supply currents as the transmission power increases. The values will need to be read from the graphs for specific Vcc and temperature conditions.

3. Power Steps & RPS (Resistor Programming System)

️· The transmitter uses a Resistor Programming System (RPS) to control the output power level.
️· Power Step Table:
- Power Step 0: < 3 kΩ (Standby)
- Power Step 1: 22 kΩ
- Power Step 2: 56 kΩ
- Power Step 3: 120 kΩ
- Power Step 4: Not Connected (highest power)

4. Frequency & Stability

️· Operating Frequency: 315 MHz
️· Frequency Stability:
- vs. Supply Voltage: ±3 ppm
- vs. Temperature: ±10 ppm

5. Timing Parameters

️· Start-up Time (ton): 1.2 - 1.5 ms (from standby to transmit mode)

6. Output Power & Performance (from AC characteristics)

️· Output Matching Network: Tuned for 5V supply
️· Spurious Emissions:
- EN 300 220-1 table 5 (0-1GHz): -36 dBm
- According to EN 300 220-1, Table 13:
■ 47MHz < f < 74MHz: -54 dBm
■ 87.5MHz < f < 118MHz: -54 dBm
■ 174MHz < f < 230MHz: -36 dBm
■ 470MHz < f < 862MHz: -36 dBm
■ f > 1GHz: -30 dBm
️· Power step 4, output power: 7.5W

7. Typical Operating Characteristics

️· The graphs show different power levels based on the temperature as well as power step.

Key Takeaways & Considerations:

️· Power Consumption: Carefully read the supply current graphs for your intended operating conditions (Vcc, temperature, power step) to ensure that your power supply can meet the transmitter's needs.
️· RPS Programming: The output power is directly controlled by the value of the resistor used in the RPS.
️· Frequency Stability: The ±10 ppm temperature stability means that the transmit frequency will drift with temperature changes. This is important for maintaining reliable communication links.
️· Spurious Emissions: Ensure that the transmitter's spurious emissions comply with regulatory requirements in your target market.