Micrel

MICRF009

January 18, 2005

13

M9999-011805

(408) 955-1690

Application Example

315MHz Receiver/Decoder Application

Figure 8 illustrates a typical application for the MICRF009

UHF Receiver IC. This receiver operates continuously (not

duty cycled) in sweep mode, and features 6-bit address

decoding and two output code bits.

Operation in this example is at 315MHz, and may be

customized by selection of the appropriate frequency

reference (Y1), and adjustment of the antenna length. The

value of C4 would also change if the optional input filter is

used. Changes from the 1kbps data rate may require a

change in the value of R1. A bill of materials accompanies

the schematic.

Figure 8. 315Mhz, 1.2kbps On-Off Keyed Receiver with Decoder

Sweep Mode

Bill of Materials

Item

Part Number

Manufacturer

Description

Qty

C1, C5

Vishay

(1)

4.7

µF ceramic or tantalum capacitor

2

C2

Vishay

(1)

0.1

µF ceramic or tantalum capacitor

1

C3

Vishay

(1)

2.2

µF ceramic or tantalum capacitor

1

C4

Vishay

(1)

8.2pF COG ceramic capacitor

1

Y1

See Crystal App. Note

9.81 ceramic resonator

1

D1

SSF-LX100LID

Lumex

(2)

Red LED

1

L1

0603CS-47NX_BC

Coil Craft

(5)

47nH Inductor

1

R1

68k, 1/4W, 5%

1

R2

Vishay

(1)

1k, 1/4W, 5%

1

U1

MICRF009

Micrel

(3)

UHF receiver

1

U2

HT-12D

Holtek

(4)

Logic decoder

1

Notes:

1.

Vishay tel: 203-268-6261

2.

Lumex tel: 800-278-5666

3.

Micrel Semiconductor

tel: 408-944-0800

4.

Holtek tel: 408-894-9046

5.

Coil Craft tel: 847-639-2361