1. Install the input low-pass filter circuit to filter out high-frequency interference, which is suitable for harsh power environment (such as car audio system).
2. The output sensitivity is adjustable and suitable for various measuring heads.
3. The most commonly used 12VDC power supply is convenient for on-board machines and PCs.
4. The power supply has reverse polarity protection function.
5. It has power pointer protection to avoid starting pointer primers and prolong the service life of the first meter.
6. Metal film resistance is 0.5W, with high power margin to ensure long-term continuous, reliable and stable operation.
7. Using the audio level, the integrated circuit chip for testing the import is designed, which contains the square root circuit of dynamic exponential compression (for example, input 1V, output 1V; input 4V, output 2V; input 9V, output 3V). The instruction is dynamic and accurate, and the pointer swings moderately, avoiding the shortcomings of small signal pointer immobility and large signal pointer rendering.
8. Without separate power supply, power can be directly extracted from the original power supply. Compared with ta7318p / ta7332p, it reduces the cost of transformer, occupies half of the chassis space and is more convenient and flexible to install.
Main parameters:
Input sensitivity: input 400Hz audio signal, measure with fluke 8025b digital multimeter AC MV file, input: 97mv, 39 level meter pointer + 3 dB position.
Power supply voltage: DC 12V 0.12A.
Backlight power supply terminal: dc10-12v 50mA. Used for backlight power supply of small bulbs.
Sensitivity of driving Vu meter and level meter: the recommended sensitivity is 500uA and the internal resistance is 630 ohm. At this time, the damping effect is the best. The damping effect of instruments of other specifications will be different and need to be further adjusted.
Note: the power supply voltage must be strictly guaranteed to be 12VDC. Although exceeding 12VDC can work for a short time, it will burn out the protection circuit for a long time. Wiring must be carried out. The live operation damage caused by this man-made fault is not within the scope of warranty.
instructions:
1. Input part:
Lin, 0, Rin, is the audio signal input terminal, which is applicable to the left, ground and right channels of CD audio output. Or it is connected to the front level input terminal selection output terminal, and should not be connected to the front level output terminal or volume potentiometer output terminal.
2. Output part:
The two +, - terminals on the side of Vu meter are outputs, which shall be connected to the +, - terminals of the two level meters respectively.
Recommended sensitivity of driven liquid level gauge: DC 100 ~ 500 shall not exceed 1mA.
On board 2 blue 3296 Series 500 ohm potentiometers can adjust the sensitivity of the two titles respectively. Rotate clockwise to increase the sensitivity.
La and LB are backlight power supply terminals, and RA and Rb are another group of backlight power supply terminals.
package list:
Vu drive board x1
