Maxim MAX2620E-D, MAX2620EUA Datasheet

MAX2620

1

VCC1

TANK

FDBK

SHDN

2

3

4

8

OUT

VCC2

GND

OUT

7

6

5

V

CC

V

CC

V

CC

V

CC

BIAS

SUPPLY

C17

1.5pF

C5

C6

1000pF

1000pF

1000pF

10Ω

CERAMIC

RESONATOR

L1

V

TUNE

900MHz BAND OSCILLATOR

1k

D1

ALPHA

SMV1204-34

1.5pF 1.5pF

51Ω

10nH

C3

2.7pF

C4
1pF

0.1µF

1000pF

OUT TO SYNTHESIZER

OUT TO MIXER

SHDN

MAX2620

10MHz to 1050MHz Integrated

RF Oscillator with Buffered Outputs

________________________________________________________________

Maxim Integrated Products

1

19-1248; Rev 1; 5/98

EVALUATION KIT

AVAILABLE

_________________General Description

The MAX2620 combines a low-noise oscillator with two
output buffers in a low-cost, plastic surface-mount,
ultra-small µMAX package. This device integrates func­tions typically achieved with discrete components. The
oscillator exhibits low phase noise when properly
mated with an external varactor-tuned resonant tank
circuit. Two buffered outputs are provided for driving
mixers or prescalers. The buffers provide load isolation
to the oscillator and prevent frequency pulling due to
load-impedance changes. Power consumption is typi­cally just 27mW in operating mode (VCC= 3.0V), and
drops to less than 0.3µW in standby mode. The MAX2620
operates from a single +2.7V to +5.25V supply.

________________________Applications

Analog Cellular Phones
Digital Cellular Phones
900MHz Cordless Phones
900MHz ISM-Band Applications
Land Mobile Radio
Narrowband PCS (NPCS)

____________________________Features

♦ Low-Phase-Noise Oscillator: -110dBc/Hz

(25kHz offset from carrier) Attainable

♦ Operates from Single +2.7V to +5.25V Supply
♦ Low-Cost Silicon Bipolar Design
♦ Two Output Buffers Provide Load Isolation
♦ Insensitive to Supply Variations
♦ Low, 27mW Power Consumption (V

CC

= 3.0V)

♦ Low-Current Shutdown Mode: 0.1µA (typ)

PART

MAX2620EUA -40°C to +85°C

TEMP. RANGE PIN-PACKAGE

8 µMAX

_______________Ordering Information

For free samples & the latest literature: http://www.maxim-ic.com, or phone [phone].
For small orders, phone [phone] ext. 3468.

MAX2620E/D -40°C to +85°C Dice*

Pin Configuration appears at end of data sheet.

*

Dice are tested at TA= +25°C, DC parameters only.

____________________________________________________Typical Operating Circuit

MAX2620

10MHz to 1050MHz Integrated
RF Oscillator with Buffered Outputs

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

DC ELECTRICAL CHARACTERISTICS

(VCC1, VCC2 = +2.7V to +5.25V, FDBK = open, TANK = open, OUT and OUT connected to VCCthrough 50Ω, SHDN = 2V,

T

A

= -40°C to +85°C, unless otherwise noted. Typical values measured at VCC1 = VCC2 = 3.0V, TA= +25°C.) (Note 1)

AC ELECTRICAL CHARACTERISTICS

(Per Test Circuit of Figure 1, VCC= +3.0V, SHDN = VCC, Z

LOAD

= Z

SOURCE

= 50Ω, PIN= -20dBm (50Ω), f

TEST

= 900MHz,

T

A

= +25°C, unless otherwise noted.)

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.

VCC1, VCC2 to GND................................................-0.3V to +6V

TANK, SHDN to GND.................................-0.3V to (V

CC

+ 0.3V)

OUT, OUT to GND...........................(V

CC

- 0.6V) to (VCC+ 0.3V)

FDBK to GND..................................(V

CC

- 2.0V) to (VCC+ 0.3V)

Continuous Power Dissipation (T

A

= +70°C)

µMAX (derate 5.7mW/°C above +70°C) .....................457mW

Operating Temperature Range

MAX2620EUA.................................................-40°C to +85°C

Junction Temperature......................................................+150°C

Storage Temperature Range.............................-65°C to +165°C

Lead Temperature (soldering, 10sec).............................+300°C

µA

0.1 2

SHDN = 0.6V

Shutdown Current

mA9.0 12.5

UNITSMIN TYP MAXCONDITIONSPARAMETER

Supply Current

V2.0Shutdown Input Voltage High
V0.6Shutdown Input Voltage Low

µA

5.5 20

SHDN = 2.0V

Shutdown Bias Current High

µA

0.5

SHDN = 0.6V

Shutdown Bias Current Low

MHz10 1050TA= -40°C to +85°C (Note 2)

UNITSMIN TYP MAXCONDITIONSPARAMETER

Frequency Range

dB50

OUT or OUT to TANK; OUT, OUT driven at P = -20dBm

Reverse Isolation

dB33

OUT to OUT

Output Isolation

Note 2: Guaranteed by design and characterization at 10MHz, 650MHz, 900MHz, and 1050MHz. Over this frequency range, the

magnitude of the negative real impedance measured at TANK is greater than one-tenth the magnitude of the reactive
impedances at TANK. This implies proper oscillator start-up when using an external resonator tank circuit with Q > 10. C3
and C4 must be tuned for operation at the desired frequency.

Note 1: Specifications are production tested and guaranteed at T

A

= +25°C and TA= +85°C. Specifications are guaranteed by

design and characterization at T

A

= -40°C.

MAX2620

10MHz to 1050MHz Integrated

RF Oscillator with Buffered Outputs

_______________________________________________________________________________________ 3

TYPICAL OPERATING CIRCUIT PERFORMANCE—900MHz Band Ceramic­Resonator-Based Tank

(Per Typical Operating Circuit, VCC= +3.0V, V

TUNE

= 1.5V, SHDN = V

CC,

load at OUT = 50Ω, load at OUT = 50Ω, L1 = coaxial

ceramic resonator: Trans-Tech SR8800LPQ1357BY, C6 = 1pF, T

A

= +25°C, unless otherwise noted.)

-110

SSB @ ∆f = 25kHz

MHz±13V

TUNE

= 0.5V to 3.0V

UNITSMIN TYP MAXCONDITIONSPARAMETER

Tuning Range

dBc/Hz

-132

SSB @ ∆f = 300kHz

Phase Noise

-6 -2At OUT (Note 2)

dBc-29Second-Harmonic Output

MHz/V11Average Tuning Gain

kHzp-p163VSWR = 1.75:1, all phasesLoad Pull
kHz/V71VCCstepped from 3V to 4VSupply Pushing

Note 3: Guaranteed by design and characterization.

dBm/Hz-147fO± >10MHzNoise Power

-11 -8

At OUT, per test circuit of Figure 1; TA= -40°C to +85°C
(Note 3)

dBm

-16 -12.5

At OUT (Note 3)

Output Power (single-ended)

TYPICAL OPERATING CIRCUIT PERFORMANCE—900MHz Band Inductor-Based Tank

(Per Typical Operating Circuit, VCC= +3.0V, V

TUNE

= 1.5V, SHDN = V

CC,

load at OUT = 50Ω, load at OUT = 50Ω, L1 = 5nH

(Coilcraft A02T), C6 = 1.5pF, T

A

= +25°C, unless otherwise noted.)

MHz/V13Average Tuning Gain

dBm/Hz-147fO± >10MHzNoise Power

kHzp-p340VSWR = 1.75:1, all phase anglesLoad Pull
kHz/V150VCCstepped from 3V to 4VSupply Pushing

-11 -8

At OUT, per test circuit of Figure 1; TA= -40°C to +85°C
(Note 3)

dBm

-16 -12.5

At OUT (Note 3)

Output Power (single-ended)

-107

SSB @ ∆f = 25kHz

MHz±15V

TUNE

= 0.5V to 3.0V

UNITSMIN TYP MAXCONDITIONSPARAMETER

Tuning Range

dBc/Hz

-127

SSB @ ∆f = 300kHz

Phase Noise

-6 -2At OUT (Note 2)

dBc-29Second-Harmonic Output

Note 3: Guaranteed by design and characterization.

MAX2620

10MHz to 1050MHz Integrated
RF Oscillator with Buffered Outputs

4 _______________________________________________________________________________________

__________________________________________Typical Operating Characteristics

(Per test circuit of Figure 1, VCC= +3.0V, SHDN = VCC, Z

LOAD

= Z

SOURCE

= 50Ω, PIN= -20dBm/50Ω, f

TEST

= 900MHz, TA= +25°C,

unless otherwise noted.)

-5

B

C

0

A:
B:

C:

10MHz BAND CIRCUIT
NOT CHARACTERIZED FOR THIS FREQUENCY BAND.
EXPECTED PERFORMANCE SHOWN.
900MHz BAND CIRCUIT

200 400 600 800 1000 1200

OUT OUTPUT POWER vs. FREQUENCY

OVER V

CC

AND TEMPERATURE

-7

MAX2620-01

FREQUENCY (MHz)

POWER (dBm)

-9

-6

-8

TA = +85°C
T

A

= +25°C

T

A

= -40°C

V

CC

= 5.25V

V

CC

= 5.25V

V

CC

= 2.7V

V

CC

= 2.7V

A

-13.0

-13.5

-12.0

-12.5

-11.0

-11.5

0 400200 600 800 1000 1200

OUT OUTPUT POWER vs. FREQUENCY

OVER V

CC

AND TEMPERATURE

MAX2620-02

FREQUENCY (MHz)

POWER (dBm)

V

CC

= 5.25V

V

CC

= 2.7V

TA = +85°C

T

A

= +25°C

T

A

= -40°C

FREQUENCY

(MHz)

REAL COMPONENT

(R in Ω)

IMAGINARY COMPONENT

(X in Ω)

250 106 163
350 68 102
450 60 96
550 35 79

1050 6.5 22.7

Table 1. Recommended Load Impedance at OUT or OUT for
Optimum Power Transfer

850

650 17.5 62.3
750 17.2 50.6

10.9 33.1

950 7.3 26.3