45MHz to 650MHz, Integrated IF

VCOs with Differential Output

MAX2605

REQUIRED INDUCTANCE vs. DESIRED VCO FIXED FREQUENCY

1900

1800

1700

1600

1500

1400

1300

1200

1100

1000

900

800

700

45

47

49

51

53

55

57

59

61

63

65

67

69

EFFECTIVE INDUCTANCE

FROM IND TO GND

INDUCTOR VALUE

MOUNTED ON EV KIT

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).

DESIRED VCO FIXED FREQUENCY (MHz)

Figure 1. MAX2605 Required Inductance vs. Desired VCO Fixed Frequency

MAX2605–MAX2609

Maxim Integrated

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