45MHz to 650MHz, Integrated IF

VCOs with Differential Output

MAX2609

REQUIRED INDUCTANCE vs. DESIRED VCO FIXED FREQUENCY

13.5

13.0

11.5

11.0

10.0

9.5

9.0

8.5

7.5

6.5

6.0

5.5

5.0

510 520 530 540

550

560

570 580 590

600 610 620 630

3.5

500

640 650

14.0

EFFECTIVE INDUCTANCE

FROM IND TO GND

INDUCTOR VALUE

MOUNTED ON EV KIT

12.5

12.0

10.5

8.0

7.0

4.5

4.0

DESIRED VCO FIXED FREQUENCY (MHz)

MEASUREMENT CONDITIONS

VCC = 2.75V, TA = 25°C,

RLOAD = 100Ω||50Ω (100Ω RESISTIVE PULL-UP PARALLELED WITH 50Ω

VNA IMPEDANCE), UNUSED OUTPUT TERMINATED IN 50

Ω,

PCB PARASITIC SHUNT CAPACITANCE (IND TO GND) = 0.45pF

THE INDUCTANCE LISTED IS THE PRECISE NOMINAL INDUCTANCE VALUE

REQUIRED FROM IND TO GND IN ORDER TO GUARANTEE THE VCO

CAN TUNE TO THE DESIRED FIXED FREQUENCY, OVER ALL OPERATING

CONDITIONS AND WORST-CASE COMPONENT

VALUES (

±2% INDUCTOR AND IC PROCESS VARIATION).

Figure 5. MAX2609 Required Inductance vs. Desired VCO Fixed Frequency

MAX2605–MAX2609

Maxim Integrated

11