FS9721_LP3

Rev. 2.1

19/39

15.1.2

FS9721_LP3 (Diagram 6, Diagram 7) Components List

No.

Spec.

No.

Spec.

No.

Spec.

No.

Spec.

No.

Spec.

R1

100kΩ

R13

28.5kΩ

R25

1.111MΩ

C6

10nF

D2

1N914

R2

1MΩ

R14

22kΩ

R26

10.000MΩ

C7

27nF

D3

Send

R3

200kΩ

R15

100kΩ

R27

100kΩ

C8

0.47μF

D4

Receiv

e

R4

82kΩ

R16

9.99Ω

R28

0.01Ω

C9

27nF

VR1

10kΩ

R5

220Ω

R17

990Ω

R29

1MΩ

C10

0.47μF

VR2

2kΩ

R6

20kΩ

R18

100kΩ

R30

1kΩ

C11

4.7nF

LCD

LCD

R7

10kΩ

R19

900kΩ

R31

1kΩ

C12

27nF

XTA

L

4MHz

R8

40kΩ

R20

100kΩ

C1

10μF

C13

27nF

IC

FS9721

_LP3

R9

90kΩ

R21

57.4kΩ

C2

10μF

C14

47nF

Batt

ery

1.5V×2

R10

100kΩ

R22

1.001kΩ

C3

10μF

C15

10μF

BP1

Buzzer

R11

100kΩ

R23

10.010kΩ

C4

10μF

C16

0.1μF

PTC

1kΩ

R12

22kΩ

R24

101.010kΩ

C5

10μF

D1

1N914

Note: The technical instructions such as the accuracy, duty and press-proof of resistance and capacitance

components are not marked in the common use circuitry and the components list, they depends on

users’ actual needs when designing the products.

15.2

Power System

C7

10μF

C3

10μF

C1

10μF

C8

10μF

C2

10μF

3V

BT1

REFI

REFO

VDDA

VB

VGG

CA

CB

VDD

AGND

VSS

FS9721_LP1

R10

40k

R7

20k

R2

200k

R3

82k

VR2

10k

RLCD

C16

0.1μF

Diagram 8

Power Circuit