Data Sheet

ADF7021

Rev. B | Page 5 of 64

SPECIFICATIONS

All measurements are performed with the EVAL-ADF7021DBx using the PN9 data sequence, unless otherwise noted.

RF AND PLL SPECIFICATIONS

Table 1.

Parameter

Min

Typ

Max

Unit

Test Conditions/Comments

RF CHARACTERISTICS

See Table 9 for required VCO_BIAS and

VCO_ADJUST settings

Frequency Ranges (Direct Output)

160

650

MHz

External inductor VCO

862

950

MHz

Internal inductor VCO

Frequency Ranges (RF Divide-by-2 Mode)

80

325

MHz

External inductor VCO, RF divide-by-2 enabled

431

475

MHz

Internal inductor VCO, RF divide-by-2 enabled

Phase Frequency Detector (PFD) Frequency1

RF/256

26/30

MHz

Crystal reference/external reference

PHASE-LOCKED LOOP (PLL)

VCO Gain2

868 MHz, Internal Inductor VCO

58

MHz/V

VCO_ADJUST = 0, VCO_BIAS = 8

434 MHz, Internal Inductor VCO

29

MHz/V

VCO_ADJUST = 0, VCO_BIAS = 8

426 MHz, External Inductor VCO

27

MHz/V

VCO_ADJUST = 0, VCO_BIAS = 3

160 MHz, External Inductor VCO

6

MHz/V

VCO_ADJUST = 0, VCO_BIAS = 2

Phase Noise (In-Band)

868 MHz, Internal Inductor VCO

−97

dBc/Hz

PFD = 19.68 MHz, VCO_BIAS = 8

433 MHz, Internal Inductor VCO

−103

dBc/Hz

PFD = 19.68 MHz, VCO_BIAS = 8

426 MHz, External Inductor VCO

−95

dBc/Hz

PFD = 9.84 MHz, VCO_BIAS = 3

Phase Noise (Out-of-Band)

−124

dBc/Hz

Normalized In-Band Phase Noise Floor3

−203

dBc/Hz

PLL Settling

40

µs

Measured for a 10 MHz frequency step to within

5 ppm accuracy, PFD = 19.68 MHz, loop

bandwidth (LBW) = 100 kHz

REFERENCE INPUT

Crystal Reference4

3.625

26

MHz

External Oscillator4, 5

3.625

30

MHz

Crystal Start-Up Time6

XTAL Bias = 20 µA

0.930

ms

XTAL Bias = 35 µA

0.438

ms

Input Level for External Oscillator7

OSC1

0.8

V p-p

Clipped sine wave

OSC2

CMOS levels

V

ADC PARAMETERS

INL

±0.4

LSB

DNL

±0.4

LSB

1

The maximum usable PFD at a particular RF frequency is limited by the minimum N divide value.

2

VCO gain measured at a VCO tuning voltage of 1 V. The VCO gain varies across the tuning range of the VCO. The software package ADIsimPLL™ can be used to model this

variation.

3

This value can be used to calculate the in-band phase noise for any operating frequency. Use the following equation to calculate the in-band phase noise performance

4

Guaranteed by design. Sample tested to ensure compliance.

5

A TCXO, VCXO, or OCXO can be used as an external oscillator.

6

Crystal start-up time is the time from chip enable (CE) being asserted to correct clock frequency on the CLKOUT pin.

7

Refer to the Reference Input section for details on using an external oscillator.