Text preview for : MY-500USB power mixer.pdf part of Guarda MY-500USB power amp schematic



Back to : MY-500USB power mixer.pdf | Home

GUARDA MY-500
( power amp circuit - one channel )

+ 49.5V
+ 49.5V
R3 R8
4,7k 4,7k
0,25W 0,25W
R16 (to speaker protection circuit)
200R




C




C
2n5551 2n5551 0,5W
B Q1 Q5 B A C




E
NPN
Q7
NPN B


E




E
2sB649
+ 470mV




C
PNP Q10
+48V




C
2n5551

C
B 2sC2073 R25
B 22pF NPN 27k
Q3 C8




E
0,25W




C
NPN 1kV
C3 D1 R9 Q12
R19
E
- 570mV 4148 20k B 2sC5200




C
0,5W 4,7R NPN
1K R6 100uF D2 R23 Q14




E
+1V 0,5W B
0,25W 25V 4148 2n5551
IN 4,7k NPN
CYF2-2C-12VDC
GND R21




E
R18 0,25W R24 C10
1
2




C1 2,2K R13 100R 0.22R 2,7k K1
R1 -49.5V




C
C5 0,25W 0,5W 5W 0,25W 10n
R11 R12 C7 Q8 100V L1
1k B
GND 2sD669
GND 0,25W 22uF C2 680R 100n
R2 33k NPN 1uH GND
47uF N.P. 0,25W




E
25V 1K R14 R26
33k +49.5V 25V
0,25W (on heatsink) R17 R22
0,25W 10R




2
1
220p
0,25W C6 100R 0.22R 1W
OUT
0,5W 5W
-1V




E
R5 C4 10n C11
D3 R10 R20 Q13
GND 1K 4148 20k 1kV - 390mV B 100n
0,25W 2sA1943 100V
0,5W 4,7R
+ 570mV 100uF PNP GND
D4




C
0,5W
E




PNP
25V J1
22pF C9




E
4148
Q4 B 1kV Q11 speaker
GND B
2sA940
2n5401 - 470mV
C




PNP
- 48V




C




C
Q9
B
2sD669
2n5401 2n5401
E




E




NPN




E
B Q2 Q6 B
R15 power supply
PNP PNP
200R
C




C




0,5W + 49.5V
VF540
F1
R4 R7 D11
4,7k 4,7k 5A
0,25W 0,25W - 49.5V D9

4700uF C12 D7
63V AC
- 49.5V D5
3 ~32V
GND 2
2SC5200 (NPN) 1 ~32V
D6
2SA1943 (PNP) 2SC2073 (NPN)
4700uF C13 D8
2SA940 (PNP) 2SD669 (NPN) 63V
2SB649 (PNP) D10
F2
2N5551 (NPN) D12
2N5401 (PNP) 5A
- 49.5V VF540
top view


B C E B C E ECB
E B C
GUARDA MY-500
(speaker protection circuit)
A
from Ch L

from Ch R
AC
B
+8,5V




1
2
( White )
FAN (12V DC)
+ 49,5V
~13,8V +15,5V
4,7k




1
2
56R
1W
100uF/63V 2W
GR GND
10k 10uF 1 2
GND
25V
220uF
E




4,7k
* 100uF/25V
B
PNP
47k GND 25V
5401




1
2
4007
C




8 +4,3V 7 +2,2V
NTR
47k Vcc Mute 4007 (on heatsink)
1
+6,4V t°
Overload ( to GND ) Thermostat
+670mV/ 110uA threshold detect 650R ( R=60 Ohm )
uPC1237 6
Relay K?
drive +0,7V CYF2-2C-12VDC
2
Offset
detect
4,7uF Latch/Auto AC Off
50V reset Vdd detect

3 5 4 +1,5V
GND 10k
4,7uF
22n 50V 0,74V threshold

GND
100k C
from Ch L

100k
from Ch R
D