Micrel, Inc.

MAQRF112

February 7, 2013

13

Revision 1.0

ASK 50

Ω Load Application Circuit

Figure 7 is an example of an ASK circuit configuration

used to drive a 50

Ω load. Table 5 lists modified values

for

both

315MHz

and

433.92MHz

configurations,

including crystal values for 315MHz and 433.92MHz

operation. The matching network values are dependent

on PCB board layout. Refer to the Micrel website for a

reference design and the PCB Gerber files

Frequency

(MHz)

L1

(nH)

C5

(pF)

L2

(nH)

C7

(pF)

C11

(pF)

Y1

(MHz)

315

470

8.2

82

8.2

2.2

9.84375

433.92

470

2.2

82

6.8

1.2

13.5600

Table 5. 50

Ω Load Matching Network

Figure 7. MAQRF112 ASK 50

Ω Evaluation Board