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RF83//RF83C/RF83L/RF83CL ASK/OOK Receiver V2.0

 

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∆t = droop recovery time

∆V = droop voltage

144mV. Using the same equation with 200nA worst case pin leakage and assuming 1µA of capacitor

leakage in the same direction, the maximum allowable ∆t (shutdown time) is about 0.56s for droop recovery

in 10ms.

The ratio of decay-to-attack time-constant is fixed at 10:1 (that is, the attack time constant is

1/10th of the decay time constant). Generally the design value of 10:1 is adequate for the vast majority of

applications. If adjustment is required the constant may be varied by adding a resistor in parallel with the

13.1.5. Step 5: Selecting the Demod Filter Bandwidth

For RF83,The inputs SEL0 and SEL1 control the demodulator filter bandwidth in four binary steps

(625Hz to 5000Hz in sweep, 1250Hz to 10000Hz in fixed mode), see Table 1. Bandwidth must be selected

according to the application. The demodulator bandwidth should be set according to equation 8.

(8) Demodulator bandwidth = 0.65 / Shortest pulse-width

It should be noted that the values indicated in table 1 are nominal values. The filter bandwidth scales

linearly with frequency so the exact value will depend on the operating frequency. Refer to the “Electrical

Characteristics” for the exact filter bandwidth at a chosen frequency.

SEL0

SEL1

Demodulator Bandwidth

Sweep Mode

Fixed Mode

1

1

5.0KHz

10KHz

0

1

2.5KHz

5KHz

1

0

1.25KHz

2.5Hz

0

0

0.625KHz

1.25Hz

Table 1. Nominal Demodulator Filter Bandwidth vs. SEL0, SEL1 and Operating Mode