LINEAR TECHNOLOGY LT5525 Technical data

FEATURES

■

Wide Input Frequency Range: 0.8GHz to 2.5GHz*

■

Broadband LO and IF Operation

■

High Input IP3: +17.6dBm at 1900MHz

■

Typical Conversion Gain: –1.9dB at 1900MHz

■

High LO-RF and LO-IF Isolation

■

SSB Noise Figure: 15.1dB at 1900MHz

■

Single-Ended 50Ω RF and LO Interface

■

Integrated LO Buffer: –5dBm Drive Level

■

Low Supply Current: 28mA Typ

■

Enable Function

■

Single 5V Supply

■

16-Lead QFN (4mm × 4mm) Package

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APPLICATIO S

■

Point-to-Point Data Communication Systems

■

Wireless Infrastructure

■

High Performance Radios

■

High Linearity Receiver Applications

LT5525

High Linearity, Low Power

Downconverting Mixer

U

DESCRIPTIO

The LT®5525 is a low power broadband mixer optimized
for high linearity applications such as point-to-point data
transmission, high performance radios and wireless infra­structure systems. The device includes an internally 50Ω
matched high speed LO amplifier driving a double-bal­anced active mixer core. An integrated RF buffer amplifier
provides excellent LO-RF isolation. The RF input balun and
all associated 50Ω matching components are integrated.
The IF ports can be easily matched across a broad range
of frequencies for use in a wide variety of applications.

The LT5525 offers a high performance alternative to
passive mixers. Unlike passive mixers, which require high
LO drive levels, the LT5525 operates at significantly lower
LO input levels and is much less sensitive to LO power
level variations.

, LTC and LT are registered trademarks of Linear Technology Corporation.
*Operation over a wider frequency range is achievable with reduced performance.
Consult factory for more information.

TYPICAL APPLICATIO

High Signal Level Frequency Downconversion

EN

BIAS

1900MHz

LNA VGA ADC

+

RF

–

RF

LT5525

LO INPUT

–5dBm

U

IF Output Power and IM3 vs

V

CC

5V DC

140MHz1900MHz

4:1

+

–

5525 TA01

0.01µF

100pF

150nH

1.2pF
150nH

V

V

CC2

CC1

IF

IF

GND

–

+

LO

LO

RF Input Power (Two Input Tones)

0

–10

–20

P

OUT

–30

–40

–50

–60

–10

TA = 25°C

= 1900MHz

f

RF

= 1760MHz

f

LO

= 140MHz

f

IF

= –5dBm

P

LO

–5

5525 TA02

–70

–80

OUTPUT POWER (dBm/TONE)

IM3

–90

–100

–15

–20

RF INPUT POWER (dBm/TONE)

0

5525f

1

LT5525

WW

W

ABSOLUTE MAXIMUM RATINGS

(Note 1)

Supply Voltage ...................................................... 5.5V

Enable Voltage ............................... –0.3V to V

LO Input Power ............................................... +10dBm

+

to LO– Differential DC Voltage ......................... ±1V

LO

+

LO

and LO– Common Mode DC Voltage... –0.5V to V

RF Input Power ................................................ +10dBm

RF+ to RF– Differential DC Voltage ..................... ±0.13V

+

RF

and RF– Common Mode DC Voltage ... –0.5V to V

IF+ and IF– Common Mode DC Voltage................... 5.5V

Operating Temperature Range ................ – 40°C to 85°C

Storage Temperature Range ................. –65°C to 125°C

Junction Temperature (TJ)................................... 125°C

U

+ 0.3V

CC

U

W

PACKAGE/ORDER INFORMATION

TOP VIEW

NC

LO+LO–NC

16 15 14 13

CC1VCC2

NC

12

GND

+

IF

11

–

IF

10

GND

9

1NC

+

RF

2

CC

CC

Consult LTC Marketing for parts specified with wider operating temperature ranges.

–

RF

NC

16-LEAD (4mm × 4mm) PLASTIC QFN

T

JMAX

EXPOSED PAD (PIN 17) IS GND,

MUST BE SOLDERED TO PCB.

NC PINS SHOULD BE GROUNDED

17

3

4

5 6 7 8

EN

V

UF PACKAGE

= 125°C, θJA = 37°C/W

ORDER PART

NUMBER

LT5525EUF

UF PART

MARKING

5525

U

DC ELECTRICAL CHARACTERISTICS

VCC = 5V, EN = 3V, TA = 25°C (Note 3), unless otherwise noted. Test circuit shown in Figure 1.

PARAMETER CONDITIONS MIN TYP MAX UNITS

Power Supply Requirements (VCC)

Supply Voltage (Note 6) 3.6 5 5.3 V

Supply Current VCC = 5V 28 33 mA

Shutdown Current EN = Low 100 µA

Enable (EN) Low = Off, High = On

EN Input High Voltage (On) 3V

EN Input Low Voltage (Off) 0.3 V

Enable Pin Input Current EN = 5V 55 µA

EN = 0V 0.1 µA

Turn-On Time (Note 5) 3 µs

Turn-Off Time (Note 5) 6 µs

AC ELECTRICAL CHARACTERISTICS

PARAMETER CONDITIONS MIN TYP MAX UNITS

RF Input Frequency Range (Note 4) Requires RF Matching Below 1300MHz 800 to 2500 MHz

LO Input Frequency Range (Note 4) 500 to 3000 MHz

IF Output Frequency Range (Note 4) Requires IF Matching 0.1 to 1000 MHz

VCC = 5V, EN = 3V, TA = 25°C. Test circuit shown in Figure 1. (Notes 2, 3)

PARAMETER CONDITIONS MIN TYP MAX UNITS

RF Input Return Loss ZO = 50Ω 15 dB

LO Input Return Loss ZO = 50Ω, External DC Blocks 15 dB

IF Output Return Loss ZO = 50Ω, External Match 15 dB

LO Input Power –10 to 0 dBm

(Notes 2, 3)

5525f

2

LT5525

AC ELECTRICAL CHARACTERISTICS

IIP3 tests, ∆f = 1MHz), f

= fRF – 140MHz, PLO = –5dBm, IF output measured at 140MHz, unless otherwise noted. Test circuit shown

LO

VCC = 5V, EN = 3V, TA = 25°C, PRF = –15dBm (–15dBm/tone for 2-tone

in Figure 1. (Notes 2, 3)

PARAMETER CONDITIONS MIN TYP MAX UNITS

Conversion Gain fRF = 900MHz –2.6 dB

= 1900MHz –1.9 dB

f

RF

= 2100MHz –2.0 dB

f

RF

f

= 2500MHz –2.0 dB

RF

Conversion Gain vs Temperature TA = –40°C to 85°C –0.020 dB/°C

Input 3rd Order Intercept fRF = 900MHz 21.0 dBm

= 1900MHz 17.6 dBm

f

RF

= 2100MHz 17.6 dBm

f

RF

f

= 2500MHz 12.0 dBm

RF

Single Sideband Noise Figure fRF = 900MHz 14.0 dB

= 1900MHz 15.1 dB

f

RF

= 2100MHz 15.6 dB

f

RF

f

= 2500MHz 15.6 dB

RF

LO to RF Leakage fLO = 500MHz to 1000MHz ≤–50 dBm

f

= 1000MHz to 3000MHz ≤–43 dBm

LO

LO to IF Leakage fLO = 500MHz to 1400MHz ≤–50 dBm

= 1400MHz to 3000MHz ≤–39 dBm

f

LO

RF to LO Isolation fRF = 500MHz to 3000MHz >38 dB

RF to IF Isolation fRF = 900MHz 62 dB

= 1900MHz 42 dB

f

RF

f

= 2100MHz 40 dB

RF

= 2500MHz 33 dB

f

RF

Input 1dB Compression fRF = 900MHz 7.6 dBm

= 1900MHz 4 dBm

f

RF

f

= 2100MHz 4 dBm

RF

= 2500MHz 3 dBm

f

RF

2RF-2LO Output Spurious Product 900MHz: fRF = 830MHz at –15dBm –63 dBc

= fLO + fIF/2) 1900MHz: fRF = 1830MHz at –15dBm –53 dBc

(f

RF

2100MHz: f
2500MHz: f

3RF-3LO Output Spurious Product 900MHz: fRF = 806.67MHz at –15dBm –74 dBc

= fLO + fIF/3) 1900MHz: fRF = 1806.67MHz at –15dBm –59 dBc

(f

RF

2100MHz: f
2500MHz: f

= 2030MHz at –15dBm –45 dBc

RF

= 2430Hz at –15dBm –42 dBc

RF

= 2006.67MHz at –15dBm –59 dBc

RF

= 2406.67Hz at –15dBm –60 dBc

RF

Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.

Note 2: The performance is measured with the test circuit shown in
Figure 1. For 900MHz measurements, C1 = 3.9pF. For all other
measurements, C1 is not used.

Note 3: Specifications over the –40°C to 85°C temperature range are
assured by design, characterization and correlation with statistical process
controls.

Note 4: Operation over a wider frequency range is possible with reduced
performance. Consult the factory for information and assistance.

Note 5: Turn-on and turn-off times correspond to a change in the output
level of 40dB.

Note 6: The part is operable below 3.6V with reduced performance.

5525f

3

LT5525

RF INPUT POWER (dBm/TONE)

–20

–100

OUTPUT POWER (dBm/TONE)

–90

–70

–60

–50

0

–30

P

OUT

IM3

–15

–10

5525 G09

–80

–20

–10

–40

–5

0

25°C
85°C
–40°C

WU

TYPICAL AC PERFOR A CE CHARACTERISTICS

= –15dBm (–15dBm/tone for 2-tone IIP3 tests, ∆f = 1MHz), fLO = fRF – 140MHz, PLO = –5dBm, IF output measured at 140MHz,

P

RF

unless otherwise noted. Test circuit shown in Figure 1.

VCC = 5V, EN = 3V, TA = 25°C, fRF = 1900MHz,

Conversion Gain and IIP3
vs RF Frequency (Low Side LO)

25

20

IIP3

15

10

5

GAIN (dB), IIP3 (dBm)

GAIN

0

–5

900

1300 1700

1100 1500

RF FREQUENCY (MHz)

1900

Conversion Gain and IIP3
vs LO Input Power

25

20

15

IIP3

10

5

GAIN (dB), IIP3 (dBm)

GAIN

0

–5

–12 –8 –4 0

LO INPUT POWER (dBm)

2100

25°C
85°C
–40°C

2300

25°C
85°C
–40°C

5525 G01

5525 G04

2500

4–14–16 –10 –6 –2 2

Conversion Gain and IIP3
vs RF Frequency (High Side LO)

25

20

IIP3

15

10

5

GAIN (dB), IIP3 (dBm)

GAIN

0

–5

900

1300 1700

1100 1500

RF FREQUENCY (MHz)

1900

SSB Noise Figure
vs LO Input Power

20

19

18

17

16

15

NOISE FIGURE (dB)

14

13

12

–14

25°C
85°C
–40°C

–12

–10

–8

LO INPUT POWER (dBm)

–6

–4

2100

–2

25°C
85°C
–40°C

2300

0

5525 G05

5525 G02

2500

2

SSB NF vs RF Frequency

20

19

18

17

16

15

14

NOISE FIGURE (dB)

13

12

11

12

900

HIGH SIDE LO

LOW SIDE LO

1100 1500

1300

RF FREQUENCY (MHz)

1700

1900

LO-IF, LO-RF and RF-LO Leakage
vs Frequency

0

–10

–20

–30

–40

LO-RF

–50

–60

LEAKAGE (dBm)

–70

–80

–90

–100

500

LO-IF

1000

FREQUENCY (MHz)

1500

RF-LO

2000

2100

2500

2300

2500

5525 G03

3000

5525 G06

Conversion Gain and IIP3
vs Supply Voltage

25

20

15

10

IIP3

5

GAIN (dB), IIP3 (dBm)

GAIN

0

–5

2.8

3.2 3.6

4

4 4.8

SUPPLY VOLTAGE (V)

25°C
85°C
–40°C

4.4 5.2 5.6

5525 G07

RF, LO and IF Port Return Loss
vs Frequency

0

–5

–10

–15

–20

RETURN LOSS (dB)

IF

–25

–30

0

RF

LO

1000 1500 2000

500

FREQUENCY (MHz)

IF Output Power and IM3 vs RF
Input Power (Two Input Tones)

2500 3000

5525 G08

5525f