Daewoo DWF-5590DP Series Service Manual page 37

BUZZER UNIT
1) CIRCUIT DIAGRAM
2) EXPLANTION OF CIRCUIT
• After the button action and total process ends, BUZZER is active.
• It is active directly with offering an output the frequency waveform of 2 KHz from the MICOM terminal No. 7
• The R7 is 'PULL UP' resistance, and R8 is restrict resistor of Q1 base current, and R5 is resistance of excess current
under phenomenon of short circuit, when the electric current changes abruptly according to the condenser component
of piezoelectric element, and R8 remove the phenomenon of abnormal oscillation by preventing the collector floating
state of Q1.
• The waveform in the part of the BUZZER DRIVE TR Q1 collector.
BUZZER INPUT UNIT
1) CIRCUIT DIAGRAM
LOAD
SELECT
37
M
R7, 10k
I
7
C
R6,1k
O
M
12V
0V
D19
D11 SW4 SW8
D12
SW3 SW7
D18
OPTION : PUMP
D25 SW6
D24 1N4148 SW5
R8,620
R5,220
Q1
C3202Y BUZZER
WES27-20P
t
f = 2 KHz
10 7
11 8
12 5
13 4
14 3
I.C6
15 2
ULN-2004
16 1
9 8
D19 SW12 D22
R66,220
D18
R67,220
D17
R68,220
SW9
D16
R69,220
12V
50 S23
51 S24
52 S25
53 S26
54 S27
RA1(4X473)
57 P100
58 P01
59 P02
60 P03