Micrel

MICRF009

January 18, 2005

2

M9999-011805

(408) 955-1690

Pin Configuration

Standard 16-Pin SOIC (M)

Demodulator Bandwidth

SEL0

Sweep-Mode

Fixed-Mode

1

1250Hz

2500Hz

0

625Hz

1250Hz

Table 1. Nominal Demodulator Filter Bandwidth vs. SEL0,

Operating Mode at 433.92 MHz

Note:

SEL0 must connect to VDD = 1 or VSS = 0. Do not float SEL0

Pin Description

Pin Number

Pin Name

Pin Function

1

SEL0

Bandwidth Selection Bit 0 (Input): Configure to set the desired demodulator filter bandwidth. See Table

1. 0 = VSS, 1 = VDD, don not float SEL0

2, 3

VSSRF

RF [Analog] Return (Input): Ground return to the RF section power supply. See “Applications

Information” for bypass capacitor details.

4

ANT

Antenna (Input): See “Applications Information” for information on input impedance. For optimal

performance the antenna impedance should be matched to the antenna pin impedance.

5

VDDRF

RF [Analog] Supply (Input): Positive supply input for the RF section of the IC. VDDBB and VDDRF

should be connected together directly at the IC pins.

6

VDDBB

Baseband [Digital] Supply (Input): Positive supply input for the baseband section of the IC. VDDBB and

VDDRF should be connected together at the IC pins.

7

CTH

[Data Slicing] Threshold Capacitor (External Component): Capacitor extracts the DC average value

from the demodulated waveform, which becomes the reference for the internal data slicing comparator.

See “Applications Information” for selection.

8

NC

No connect.

9

VSSBB

Baseband [Digital] Return (Input): Ground return to the baseband section power supply. See

“Applications Information” for bypass capacitor and layout details.

10

DO

Digital Output (Output): CMOS level compatible data output signal.

11

SHUT

Shutdown (Input): Shutdown-mode logic-level control input. Pull low to enable the receiver. This input

has an internal pulled-up to VDDRF.

12

CAGC

AGC Capacitor (External Component): Integrating capacitor for on-chip AGC (automatic gain control).

See “Applications Information” for capacitor selection.

13

SEL1

Bandwidth Selection Bit 1 (Input): Must tie to ground. Reserved for future use.

14

REFOSC2

Reference Oscillator (External Component or Input): Timing reference for on-chip tuning and

alignment.

15

REFOSC1

Reference Oscillator (External Component or Input): Timing reference for on-chip tuning and

alignment.

16

SWEN

Sweep-Mode Enable (Input): Sweep- or fixed-mode operation control input. When SWEN is high, the

MICRF009 is in sweep mode; when SWEN is low, the receiver operates as a conventional single-

conversion superheterodyne receiver. This pin is internally pulled-up to VDDRF.