MAX2607EUT datasheet(6/15 Pages) MAXIM

Part #	MAX2607EUT

Description	45MHz to 650MHz, Integrated IF VCOs with Differential Output

Download	15 Pages

Scroll/Zoom	100%

Manufacturer	MAXIM [Maxim Integrated Products]

Direct Link	https://www.maximintegrated.com/en.html

Logo

6 / 15 page

45MHz to 650MHz, Integrated IF

VCOs with Differential Output

Detailed Description

The MAX2605–MAX2609 are low-noise VCOs designed

for fixed/single-frequency IF applications. The core

oscillator circuit is based on the well-known Colpitts

topology. The varactor and feedback capacitors are

integrated on-chip so that only an external inductor is

required to establish the frequency of oscillation and

produce a properly operating VCO. The tuning range,

biasing, startup, etc., are all managed within the IC. This

highly integrated design dramatically simplifies the

parts’ application.

The tuning range is wide enough so that, with the use

of ±2% tolerance inductors, no board-level adjustments

to the oscillation frequency are necessary. Once the

correct inductor value is chosen, the VCO is guaran-

teed always to tune to the desired operating frequency.

In addition, with the use of inductors of moderate Q (35

to 40), the VCO achieves excellent phase-noise perfor-

mance.

Applications Information

Desired Oscillation Frequency

The desired VCO operating frequency is set by the

value of the external inductance, LF. Figures 1–5 show

the inductance value LF required to achieve the desired

oscillation frequency. The inductor value can be taken

directly from these figures. Inductance must be select-

ed accurately to ensure proper operation over all con-

ditions.

Inductor Implementation

The inductance value required for the desired operat-

ing frequency may not necessarily coincide with a stan-

dard-value SMT inductor, which typically increases size

in ~1.2x steps. In such cases, the inductance must be

constructed from two inductors, LF1 and LF2, in order to

achieve the desired inductance value. Choose LF1 to

be a standard-value inductor with a value just less than

that required for LF. Choose LF2 to be a standard-value

inductor with a value just less than (LF - LF1). LF1

should adhere to the minimum Q requirements, but LF2

may be implemented as a lower-cost, lower-Q, thin-film

SMT inductor. Its lower Q has only a small impact on

the overall Q of the total inductance because it is <20%

of the total inductance. However, the overall Q of LF1

and LF2 must be greater than the minimum inductor Q

(Table 1).

It is also permissible to use PC board traces to provide

a small amount of inductance, thereby adjusting the

total inductance value. On the MAX2608/MAX2609, the

inductance values for LF2 are sometimes more exactly

implemented as a PC board trace (shorted to GND),

rather than an SMT inductor. When designing LF with

two inductors, use the simple model in Figure 7 to cal-

culate XL and LEQ.

The LF in Figures 1–5 represents an equivalent induc-

tance as seen by pin 1 (IND). The equivalent induc-

tance corresponds to the inductive reactance

connected to IND at the desired oscillation frequency

(fNOMINAL).

LEQ = XL / (2

π fNOMINAL) as seen in Figure 8

Design LEQ = LF at the desired fNOMINAL. The

MAX2605–MAX2609 are designed to tolerate approxi-

mately 0.5pF of external parasitic capacitance at IND.

This parasitic capacitance arises from the pad capaci-

tance at the device pin and pads for the inductor.

Additional shunt capacitance is not recommended

because it degrades the tuning range.

Bypass Capacitor on TUNE

The MAX2605–MAX2609’s oscillator design uses a vari-

ant of the Colpitts topology, where DC bias for the var-

actor is applied via a DC voltage on TUNE and a

ground connection through the external inductor LF.

TUNE must also have a high-frequency AC ground for

Table 1. External Inductor LF Range

Table 2. CBYPASS Values

40

3.9

≤ LF ≤ 15

500 to 650

MAX2609

40

35

MIN

INDUCTOR

Q

10

≤ LF ≤ 47

300 to 500

MAX2608

39

≤ LF ≤ 180

150

≤ LF ≤ 820

680

≤ LF ≤ 2200

INDUCTANCE

RANGE

(nH)

FREQUENCY

RANGE

(MHz)

45 to 70

70 to 150

150 to 300

MAX2607

MAX2606

MAX2605

PART

≥ 39 pF

MAX2609

≥ 100 pF

MAX2608

≥ 330 pF

≥ 680 pF

≥ 820 pF

CBYPASS

MAX2607

MAX2606

MAX2605

DEVICE

MAX2605–MAX2609

6

Maxim Integrated

Similar Part No. - MAX2607EUT

Manufacturer	Part #	Datasheet	Description
Maxim Integrated Produc...	MAX2607EUT-T	312Kb / 15P	45MHz to 650MHz, Integrated IF VCOs with Differential Output Rev 0a; 4/02
Maxim Integrated Produc...	MAX2607EUT-T	324Kb / 15P	Integrated IF VCOs with Differential Output Rev 0a; 4/02

More results

Similar Description - MAX2607EUT

Manufacturer	Part #	Datasheet	Description
Maxim Integrated Produc...	MAX2605	312Kb / 15P	45MHz to 650MHz, Integrated IF VCOs with Differential Output Rev 0a; 4/02
Maxim Integrated Produc...	MAX2609EUT	324Kb / 15P	Integrated IF VCOs with Differential Output Rev 0a; 4/02
Silicon Laboratories	SI2200	824Kb / 30P	RF SYNTHESIZER WITH INTEGRATED VCOS INTEGRATED VCOS
Texas Instruments	CDCE62002	1Mb / 49P	[Old version datasheet] Four Output Clock Generator/Jitter Cleaner With Integrated Dual VCOs
Silicon Laboratories	SI4136	660Kb / 30P	ISM RF SYNTHESIZER WITH INTEGRATED VCOS
Texas Instruments	CDCE62005	2Mb / 80P	[Old version datasheet] Five/Ten Output Clock Generator/Jitter Cleaner With Integrated Dual VCOs
Texas Instruments	CDCE62005	2Mb / 76P	[Old version datasheet] Five/Ten Output Clock Generator/Jitter Cleaner With Integrated Dual VCOs
National Semiconductor ...	LMX2522	189Kb / 18P	PLLatinum Frequency Synthesizer System with Integrated VCOs
Qorvo, Inc	RFMD2080	3Mb / 19P	45MHz TO 2700MHz IQ MODULATOR WITH 45MHz TO 2700MHz IQ MODULATOR WITH
STMicroelectronics	STW81101	1Mb / 42P	Multi-band RF frequency synthesizer with integrated VCOs

More results

MAX2607EUT Datasheet(PDF) 6 Page - Maxim Integrated Products

MAX2607EUT Datasheet(HTML) 6 Page - Maxim Integrated Products

Similar Part No. - MAX2607EUT

Similar Description - MAX2607EUT

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Datasheet Download

Link URL