atr2730 ATMEL Corporation, atr2730 Datasheet - Page 16

• Manufacturer Part Number: atr2730
• Description: L-band Down-converter For Dab Receivers
• Manufacturer: ATMEL Corporation

11. Application Circuit for External LO Signal
16
ATR2730 [Preliminary]
With an external LO signal it is possible to overdrive the VCO. In this case, the internal VCO acts
as an LO buffer.
Figure 11-1. Application Circuit for External LO Signal
Figure 11-2. Reference Oscillator Operation
Figure 11-3. Reference Oscillator Overdriven
Reference
signal
Quartz
crystal
External LO signal
(50 signal gen.)
P
LO
68 pF
L1
= -10 dBM
33 pF
18 pF
OSCB
OSCE
C1
OSCB
OSCE
50
100 pF
1 nF
470 nH
Reference divider
VREF
TANK
Reference divider
4903C–DAB–03/07