The scenario
A DIY audio amplifier needs remote-controlled volume with visual feedback. The PT2258 provides two-channel digital volume control via I2C, driven by an ATmega328 that reads an IR remote and displays level on 7-segment LEDs.
What is in this drawing
Read the decisions behind it.
01
Use I2C pull-up resistors (4.7k) on SDA/SCL for reliable communication
02
Add input 10k bias resistors and output 47k load resistors to avoid floating pins
03
Drive 7-segment LEDs through 220Ω current-limiting resistors from MCU GPIO
Reusable for any DIY preamp or integrated amplifier project needing remote volume and display.
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