PT4456

PRE1.1

2

September 2014

APPLICATION CIRCUIT

XOUT

1

VSS

2

PAOUT

3

DIN

4

VDD

5

XIN

6

PT4456

X1

R2

R1

DIN

VDD

C5

C4

L2

L1

C3

C6

C1

C2

R3

R4

C7

R5

BILL OF MATERIALS

Part

Value

Unit

Notes

315MHz

433.92MHz

X1

9.84175M

13.558M

Hz

3,4,5

R1

10K

10K

Ω

R2

100K

100K

Ω

R3

0

0

Ω

R4

10

10

Ω

R5

560K

560K

Ω

3

C1

10p

10p

F

1,5

C2

10p

10p

F

1,5

C3

1μ

1μ

F

C4

220p

220p

F

C5

8.2p

4.7p

F

2

C6

18p

10p

F

2

C7

2.2μ

2.2μ

F

L1

180n

180n

H

L2

33n

27n

H

2

Notes:

1.

C1/C2 can be used to trim the transmitted signal frequency for matching the specified value.

2.

L2/C5/C6 value will depend on PCB layout.

3.

The recommend maximum ESR value of X1 is 40

Ω. To populate R5 over XIN will help to maintain good oscillation in high X1 ESR.

4.

For FSK application to have adequate frequency deviation, and accurate carrier frequency, the crystal resonator frequency will be lower than the

specified value. The recommended crystal resonator frequency is 9.84175MHz and 13.558MHz.

5.

For higher X1 ESR, load capacitor C2 can be reduced or removed to maintain good oscillation. In narrowband application with accurate frequency

requirement, trimming the C1 capacitor or change the crystal resonator frequency is suggested.

6.

The PCB layout is scaled to get good reading. The actual PCB size is about 1.1x1.3 cm