jedyne do czego mogę mieć zastrzeżenie to jakość zdjęć zawartych w przesłanej instrukcji serwisowej ponieważ są fatalnej jakości, praktycznie nieczytelne. tak poza tym jestem zadowolony to jest to czego szukałem.
Instrukcja jest OK. Schematy czytelne, opisane niektóre procedury.
Tekstowy podgląd strony 42 (kliknij aby zobaczyć)
SD-AT50W
WAVEFORMS OF 1-BIT CIRCUIT
2.00V/div AD IC Output 2.00V/div + Side
2.00 V/div 2.00 V/div LEVEL SHIFT OUT
T
1 2
5V
T
2
5 6
DEAD TIME
1
- Side 500 ns/div Amplitude from 0 to 5 V 194.545465 µs 520 mV
50.0 ns/div 0.0 s -12.30 V Dead time is generated by level shift input. Leading edge is delayed at CR, passing R at DI. Set value: 20 - 25 nsec.
ZOOM UP
2.00 V/div
2.00 V/div
10.0 V/div
10.0 V/div
3
2
+ FETOUT + SIDE
2
11
AD IC NF IN
T
12
1
- SIDE
1
4
500 ns/div 194.545465 µs -12.30 V
500 ns/div Waveforms before low-pass filters at both ends of the speaker. H-bridge may be considered as BTL. However, here and at the gate drive, dead time is not observed; since bootstrap operates based on output, DEAD TIME part is in floating condition. The waveform on the HIGH side shows that only the booted voltage lowers. 194.545465 µs -12.3 V
In partial pressure OUT, 4 to 7 V amplitude of GND reference is observed. In IC of 75 kohms, the reference is 2.5 V because of VREF. Due to imaginary GND of operational amplifier inside IC, the waveform cannot be monitored. This waveform is partial pressure OUT.
