Appendix C Recommended Circuit For Buzzer Connection; Recommended Circuit For Electromagnetic Buzzer Connection - Epson Buzzer S1C31D51 Manual

Appendix C Recommended circuit for Buzzer connection

C.1

Recommended circuit for Electromagnetic buzzer connection

Figure C.1.1 shows the recommended circuit when connecting the electromagnetic buzzer. Select the resistance
R1 to R4 in Fig C.1.1 so that they are optimized for the electromagnetic buzzer to be connected. Table C.1.1
shows the recommended resistance values for each electromagnetic buzzer made by TDK corporation. These
values are calculated from the supply voltage to electromagnetic buzzer (VDD1) and specification of DC
resistance, maximum current.
Note that the board may be damaged by a large current if both transistor Q1/Q2 switch on when (a)/(b) are in the
Hi-Z. Therefore, when using this recommended circuit, do not supply VDD1 power while (a)/(b) are in the Hi-z.
S1C31D51
S1C31D51
Fig C.1.2 The circuit to control power supply(VDD1) for electromagnetic buzzer
The circuit shown in Figure C.1.2 is implemented on S5U1C31D51T2 to control power supply (VDD1) for
electromagnetic buzzer. In the demo software described in Chapter 4, this circuit avoids (a)/(b) becoming Hi-Z
state by Pxx=L(VDD1=ON) before the start of speech playback and Pxx=H(VDD1=OFF) after the end of
playback to prevent a large current.
S5U1C31D51T2 Manual
(Rev.1.0)
TOUT00
(a)
(b)
TOUT01
Fig C.1.1 Recommended circuit for electromagnetic buzzer
3.3V / 5V
33kΩ
Pxx
Pxx = L: VDD1 ON
Pxx = H(Hi-Z): VDD1 OFF
Seiko Epson Corporation
VDD1
R1
Q1A
R2
Q2A
VDD1
R3
Q1B
R4
Q2B
Q3
BZ1
VDD1
8