Micrel, Inc.

MICRF008

August 2008

4

M9999-080108

Notes:

1. Exceeding the absolute maximum rating may damage the device.

2. The device is not guaranteed to function outside its operating rating.

3. Devices are ESD sensitive, use appropriate ESD precautions. Meets class 1 ESD test requirements, (human body model HBM), in accordance with

MIL-STD-883C, method 3015. Do not operate or store near strong electrostatic fields.

4. Specification for packaged product only.

a return-to-zero (RZ) waveform with 50% average duty cycle at a data rate of 1kbps (Manchester encoded). The RF input is assumed to be matched

into 50Ω.

6. Sensitivity, a commonly specified receiver parameter, provides an indication of the receiver’s input referred noise, generally input thermal noise.

However, it is possible for a more sensitive receiver to exhibit range performance no better than that of a less sensitive receiver if the background

noise is appreciably higher than the thermal noise. Background noise refers to other interfering signals, such as FM radio stations, pagers, etc.

A better indicator of achievable receiver range performance is usually given by its selectivity, often stated as intermediate frequency (IF) or radio

frequency (RF) bandwidth, depending on receiver topology. Selectivity is a measure of the rejection by the receiver of ambient noise. More selective

receivers will almost invariably provide better range. Only when the receiver selectivity is so high that most of the noise on the receiver input is

actually thermal will the receiver demonstrate sensitivity-limited performance.

new parameter value as the ratio:

3.36MHz)

at

value

(parameter

3.36MHz

MHz

REFOSC

f

×

8. Spurious reverse isolation represents the spurious components which appear on the RF input pin (ANT) measured into 50Ω with an input RF

matching network

9. Series resistance of the resonator (ceramic resonator or crystal) should be minimized to the extent possible. In cases where the resonator series

resistance is too great, the oscillator may oscillate at a diminished peak-to-peak level, or may fail to oscillate entirely. Micrel recommends that series

resistances for ceramic resonators and crystals not exceed 50Ω and 100Ω respectively.

new parameter value as the ratio:

3.36MHz)

at

value

(parameter

MHz

REFOSC

f

3.36MHz

×