3D tone circuit made by LM4610

LM4610 is a new high-end HIFI-level tone integrated circuit launched by NS Corporation of the United States after LM1036. It is an ideal replacement for LM1036. It also uses DC voltage to adjust the volume, treble, bass and balance of two channels. This IC also adds 3D sound field expansion adjustment based on LM1036. It also has an equal loudness switch to compensate for the human ear characteristic curve at low volume.

Main features of LM4610:  
(1) Operating voltage: 9~16V Current: 35mA Input impedance is 30K, output impedance is as low as 20 ohms  
(2) Treble adjustment range: ±16DB (at 16KHZ)  
 (3) Bass adjustment range: ±15DB (at 40KHZ)
(4) Balance adjustment range: 1∽20DB
(5) Volume adjustment range: 75DB
(6) Signal-to-noise ratio: 80DB
(7) Frequency response: 250KHZ
(8) Total harmonic distortion: 0.0003  

Circuit principle:
     The typical application circuit of LM4610 is shown in the figure below. The 19th pin of LM4610 outputs a reference voltage of 5.4V. The voltage of each control pin is adjusted through four 47K potentiometers to change between 0→5.4V, thereby controlling the volume, tone, and balance. Switch S1 is a 3D sound effect switch, and S2 is an equal loudness switch.

The tone control of LM4610 is related to the treble capacitor Ct and the bass capacitor Cb. When the treble capacitor Ct = 0.01uF and the bass capacitor Cb = 0.39uF, the boost and attenuation in the range of 40HZ-60HZ is ±15dB.

The following is the PCB diagram

The component layout is as follows