MICRF007

Micrel

MICRF007

14

December 2000

SEL0

VSSRF

REFOSC

ANT

CAGC

VDD

SHUT

CTH

DO

C2

2.2

µF

4.8970MHz

Y1

U1 MICRF002

4.7

µF

Optional Filter

8.2pF, 16.6nH

pcb foil inductor

1in of 30mil trace

C4

L1

+5V

Supply

Input

C1

4.7

µF

A0

VDD

A1

VT

A2

OSC1

A3

OSC2

A4

DIN

A5

D11

A6

D10

A7

D9

U2 HT-12D

VSS

D8

R1

68k

R2

1k

Code Bit 0

Code Bit 1

RF

(Analog)

Ground

Baseband

(Digital)

Ground

0.4

monopole

antenna (11.6in)

6-bit

address

Figure 7a. 315MHz, 1kb/s On-Off Keyed Receiver/Decoder

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Figure 7b. Bill of Material

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Figure 7c. Component Vendors

315.0MHz Receiver/Decoder Application

Figure 7a illustrates a typical application for the MICRF007

UHF Receiver IC. This receiver operates continuously (not

duty cycled), and features 6-bit address decoding and two

output code bits.

Operation in this example is at 315.5MHz, and may be

customized by selection of the appropriate frequency refer-

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

of C4 would also change if the optional input filter is used.

Changes from the 1kb/s data rate may require a change in the

value of R1. A bill of materials accompanies the schematic.