PU2CLR AKC695X Arduino Library
AKC695X device family offer versatile FM/MW/SW/LW receiver solution
by reducing the external components usually found in regular receivers. This device family will surprise hobbyists and experimenters with its simplicity to build FM and AM (LW, MW, SW) receivers.
There are currently some receivers based on DSP technology. The KT0915 and SI4735 devices are some examples widely disseminated in the market. This library was developed with the purpose of expanding the alternatives to hobbyists and radio listeners.
In this document you will see Arduino source codes, schematics, examples and tips to help you to build a receiver based on Arduino board and AKC695X devices. The project and examples shown here do not intend to be a real receiver for exigent listener. However, it is possible to start with it and after add some improvements. On the other hand, with the simple circuits shown here, the experimenter may be surprised with the AKC695X performance.
Supplies
Component parts
Name / Label Description AKC6955 SSOP24 DSP receiver from AKC. You also can use AKC5951 (just FM and AM/MW) or AKC6959sx Arduino Board It can be an Atmega based board, SMT32, ESP32, Attiny or another compatible Arduino board Y1 32.32.768KHz or 12MHz crystal oscillator. By default this library uses 32.768KHz. But, you can set it to deal with 12MHz crystal. See API Documentation. C1 and C2 22pF Ceramic or Tantalum capacitor C3 470uF Electrolytic capacitor C4 1nF Ceramic or Tantalum capacitor C4 1nF Ceramic or Tantalum capacitor C5 and C8 100nF Ceramic or Tantalum capacitor C6 100pF Ceramic or Tantalum capacitor C7 3nF Ceramic or Tantalum capacitor C9 22uF Electrolytic capacitor R1 10K resistor R2 22K resisto. This value is not critical. Use something closer to 25K R3 4.7K resistor. This value is not critical. Use something closer to 5K LED1 regular LED L1 Ferrite Rod Coil for LW and MW. It is very common in old medium wave receiversAKC695X Pin definitions
The figure and table below show the pin description of the AKC6951 and AKC6955.
Pin Name Description 1 oscin Bonding or passive 32.768K 12MHz crystal to ground, or receive an external clock reference signal 2 oscout Passive other end connected to the crystal, when connected to an external clock, this pin floating 3 gnd Close to ground 4 tund Radio lock indicator pin, connected directly to the light emitting diode; Tuning the MCU software when the pin may also be used as a stop sign 5 p_on On-chip power switch, high input power chip; the chip down in a low-power standby state, power consumption of approximately 10uA 6 sclk 2C clock signal input 7 sdio I²C bidirectional data signal input / output 8 inl External audio signal input L, proposes to add blocking capacitor 1uF 9 inr External audio input signal R, proposes to add blocking capacitor 1uF 10 vbat Then the power pins need to pay attention to the nearest ground 0.1uF decoupling capacitance to ground 11 lout Left channel audio output 12 gnd gnd 13 rout Right channel audio output 14 vref Precision 1.5V output pin, to provide a baseline volume potentiometer 15 vol Variable volume potentiometer connected end, the fixed end of a potentiometer directly connected to VREF, and the other end through a resistor to ground. The resistance ratio of the resistor and potentiometer as 1: 2 16 vbat Then the power pins need to pay attention to the nearest ground 0.1uF decoupling capacitance to ground 17 gnd Close to ground 18 mwinN MW and LW differential input signal 19 mwinP MW and LW differential input signal 20 swin Shortwave signal input terminal, note add blocking capacitor recommended 3nF 21 gnd Close to ground 22 fmin FM radio frequency signal input terminal, note add blocking capacitor, 100pF recommendations 23 ldocap Internal LDO output pin, nearest the need decoupling capacitors, recommendations 47uF 24 gnd Close to groundSee all documentation on