u2730b-n ATMEL Corporation, u2730b-n Datasheet - Page 15

• Manufacturer Part Number: u2730b-n
• Description: L-band Down-converter For Dab Receivers
• Manufacturer: ATMEL Corporation

Application Circuit
for External LO
Signal
4719A–DAB–05/03
With an external LO signal it is possible to overdrive the VCO. In this case, the internal
VCO acts as a LO buffer.
Figure 9. Application Circuit for External LO Signal
Figure 10. Reference Oscillator Operation
Figure 11. Rerference Oscillator Overdriven
Reference signal
Quartz crystal
(50 W signal gen.)
P
ext. LO signal
L1
LO
68 pF
= -10 dBm
33 pF
18 pF
C1
OSCB
OSCB
50
OSCE
OSCE
100 p
1 n
470 nH
TANK
VREF
Reference devider
Reference devider
U2730B-N
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