XR2211 View Datasheet(PDF) - Exar Corporation
Part Name
Description
MFG CO.
'XR2211' PDF : 24 Pages View PDF
XR-2211
DESIGN EQUATIONS
(All resistance in W, all frequency in Hz and all capacitance in farads, unless otherwise specified)
(See Figure 3 for definition of components)
1. VCO Center Frequency, fO:
fO
+
1
R0·C0
2. Internal Reference Voltage, VREF (measured at pin 10):
ǒ Ǔ VREF +
VCC
2
–650mV in volts
3. Loop Low-Pass Filter Time Constant, t:
t + C1·RPP (seconds)
where:
ǒ Ǔ RPP +
R1·RF
R1 ) RF
if RF is 1 or CF reactance is 1, then RPP = R1
4. Loop Damping, j:
Ǹǒ Ǔ z +
1250·C0
R1·C1
Note: For derivation/explanation of this equation, please see TAN-011.
5. Loop-tracking
bandwidth,
"+
Df
f0
Df
f0
+
R0
R1
Tracking
Bandwidth
Df
Df
fLL
f1
fO
f2
fLH
Rev. 3.01
8
Share Link: 
