Linear LTC6605-10 Schematic [ru]

LTC6605-10

Dual Matched 10MHz Filter

with Low Noise, Low Distortion

Differential Ampliﬁ er

FEATURES

Two Matched 10MHz 2nd Order Lowpass Filters

with Differential Ampliﬁ ers

Gain Match: ±0.35dB Max, Passband Phase Match: ±1.2° Max, Passband

Single-Ended or Differential Inputs

< –90dBc Distortion in Passband

2.1nV/√Hz Op Amp Noise Density

Pin-Selectable Gain (0dB/12dB/14dB)

Pin-Selectable Power Consumption (0.35mA/

16.2mA/33.1mA)

Rail-to-Rail Output Swing Adjustable Output Common Mode Voltage Control Buffered, Low Impedance Outputs

2.7V to 5.25V Supply Voltage

Small 22-Pin 6mm × 3mm × 0.75mm DFN Package

APPLICATIONS

Broadband Wireless ADC Driver/Filter

Antialiasing Filter

Single-Ended to Differential Conversion

DAC Smoothing Filter

Zero-IF Direct Conversion Receivers

DESCRIPTION

The LTC®6605-10 contains two independent, fully differential ampliﬁ ers conﬁ gured as matched 2nd order 10MHz lowpass ﬁ lters. The f range of 9.7MHz to 14MHz.

The internal op amps are fully differential, feature very low noise and distortion, and are compatible with 16-bit dynamic range systems. The inputs can accept singleended or differential signals. An input pin is provided for each ampliﬁ er to set the common mode level of the differential outputs.

Internal laser-trimmed resistors and capacitors determine a precise, very well matched (in gain and phase) 10MHz 2nd order ﬁ lter response. A single optional external resistor per channel can tailor the frequency response for each ampliﬁ er.

Three-state BIAS pins determine each ampliﬁ er’s power consumption, allowing a choice between shutdown, medium power or full power.

The LTC6605-10 is available in a compact 6mm × 3mm 22-pin leadless DFN package and operates over a –40°C to 85°C temperature range.

, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners.

of the ﬁ lters is adjustable in the

–3dB

TYPICAL APPLICATION

Dual, Matched 9.7MHz Lowpass Filter

INA

–

INB

–

LTC6605-10

–

660510 TA01

0.1μF

Channel to Channel Phase Matching

120

352 TYPICAL UNITS

= 25°C

–

OUTA

–

OUTB

= 10MHz

100

NUMBER OF UNITS

–1.0

–0.6 –0.2–0.4–0.8

0 0.6 0.80.40.2 1.0

PHASE MATCH (DEG)

660510 TA01b

660510f

LTC6605-10

(Note 1)

PIN CONFIGURATION ABSOLUTE MAXIMUM RATINGS

Total Supply Voltage (V+ to V–) ................................5.5V

Input Current (Note 2) ..........................................±10mA

Output Short-Circuit Duration (Note 3) ............ Indeﬁ nite

Operating Temperature Range (Note 4).... –40°C to 85°C

Speciﬁ ed Temperature Range (Note 5) ....–40°C to 85°C

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

Storage Temperature Range ................... –65°C to 150°C

ORDER INFORMATION

TOP VIEW

+IN4 A

+IN1 A

BIAS A

–IN1 A

–IN4 A

–

+IN4 B

+IN1 B

BIAS B

–IN1 B

–IN4 B

22-LEAD (6mm × 3mm) PLASTIC DFN

EXPOSED PAD (PIN 23) IS V

DJC PACKAGE

= 150°C, θJA = 46.5°C/W

JMAX

–OUT A

–

OCMA

+OUT A

–

–OUT B

–

OCMB

+OUT B

–

, MUST BE SOLDERED TO PCB

LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE

LTC6605CDJC-10#PBF LTC6605CDJC-10#TRPBF 660510 22-Lead (6mm × 3mm) Plastic DFN 0°C to 70°C LTC6605IDJC-10#PBF LTC6605IDJC-10# TRPBF 660510 22-Lead (6mm × 3mm) Plastic DFN –40°C to 85°C Consult LTC Marketing for parts speciﬁ ed with wider operating temperature ranges. *The temperature grade is identiﬁ ed by a label on the shipping container.

Consult LTC Marketing for information on non-standard lead based ﬁ nish parts. For more information on lead free part marking, go to: http://www.linear.com/leadfree/

For more information on tape and reel speciﬁ cations, go to: http://www.linear.com/tapeandreel/

DC ELECTRICAL CHARACTERISTICS

The l denotes the speciﬁ cations which apply over the full operating temperature range, otherwise speciﬁ cations are at TA = 25°C. V+ = 3V, V– = 0V, V R

= 10k. The ﬁ lter is conﬁ gured for a gain of 1, unless otherwise noted. VS is deﬁ ned as (V+ – V–). V

BAL

–OUT

)/2. V

is deﬁ ned as (V

INCM

INP

+ V

INM

)/2. V

is deﬁ ned as (V

OUTDIFF

+OUT

– V

INCM

–OUT

). V

= V

= mid-supply, BIAS tied to V+, RL = Open,

OCM

is deﬁ ned as (V

INDIFF

is deﬁ ned as (V

OUTCM

– V

INP

). See Figure 1.

INM

+OUT

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

Differential Offset Voltage (at Op Amp

VS = 2.7V to 5V

±0.25 ±1 mV

Inputs) (Note 6)

ΔVOS/ΔT Differential Offset Voltage Drift (at Op

Amp Inputs)

Input Bias Current (at Op Amp Inputs) (Note 7)

Input Offset Current

BIAS = V

BIAS = Floating BIAS = V

BIAS = Floating

l l

–60

–30

±1 ±1

–25

–12.5

μV/°C μV/°C

0 0

μA μA

±1 μA

(at Op Amp Inputs) (Note 7)

660510f

LTC6605-10

DC ELECTRICAL CHARACTERISTICS

The l denotes the speciﬁ cations which apply over the full operating temperature range, otherwise speciﬁ cations are at T R

= 10k. The ﬁ lter is conﬁ gured for a gain of 1, unless otherwise noted. VS is deﬁ ned as (V+ – V–). V

BAL

–OUT

)/2. V

is deﬁ ned as (V

INCM

INP

+ V

INM

)/2. V

= 25°C. V+ = 3V, V– = 0V, V

is deﬁ ned as (V

OUTDIFF

+OUT

– V

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

INCM

Input Common Mode Voltage Range (Note 8)

CMRR Common Mode Rejection Ratio

(ΔV

/ΔVOS) (Note 9)

INCM

PSRR Power Supply Rejection Ratio

(ΔV

/ΔVOS) (Note 10)

V R V

V I

OSCM

OCM

MID

VOCM

OUT

Common Mode Offset Voltage (V

– V

OUTCM

OCM

)

Output Common Mode Range (Valid Range for V

Self-Biased Voltage at the V Input Resistance of V Output Voltage Swing, High

(Measured Relative to V

Output Voltage Swing, Low (Measured Relative to V

Pin) (Note 8)

OCM

)

–

)

OCM

Output Short-Circuit Current (Note 3) VS = 3V

Supply Voltage Supply Current (per Channel) VS = 2.7V to 5V; BIAS = V

Pin VS = 3V

VS = 3V V

= 5V

= 3V; ΔV

= 5V; ΔV

= 2.7V to 5V

= 3V

= 5V

= 3V

= 5V

= 3V; IL = 0mA

= 3V; IL = 5mA

= 3V; IL = 20mA

= 5V; IL = 0mA

= 5V; IL = 5mA

= 5V; IL = 20mA

= 3V; IL = 0mA

= 3V; IL = –5mA

= 3V; IL = –20mA

= 5V; IL = 0mA

= 5V; IL = –5mA

= 5V; IL = –20mA

= 5V

INCM INCM

= 1.5V = 2.5V

VS = 2.7V to 5V; BIAS = Floating V

= 2.7V to 5V; BIAS = V

R t t

BIAS

OFF

BIAS Pin Range for Shutdown Referenced to V BIAS Pin Range for Medium Power Referenced to V BIAS Pin Range for Full Power Referenced to V BIAS Pin Self-Biased Voltage (Floating) Referenced to V BIAS Pin Input Resistance Turn-On Time VS = 3V, V Turn- O f f Time VS = 3V, V

BIAS

–

= V– to V = V+ to V

–

–OUT

–

INCM

). V

= V

= mid-supply, BIAS tied to V+, RL = Open,

OCM

is deﬁ ned as (V

INDIFF

l l

l l l

l l

l l l

–0.2 –0.2

1.1

1.475 1.5 1.525 V

12.5 18 23.5 kΩ

±40 ±50

2.7 5.25 V

2.3 V

1.05 1.15 1.25 V 100 150 200 kΩ

is deﬁ ned as (V

OUTCM

– V

INP

46 46

). See Figure 1.

INM

74 74

66 95 dB

±10 ±10

245 285 415

350 390 550

120 135 195

175 200 270

±70 ±95

33.1

16.2

0.35

00.4V

11.5V

400 ns 400 ns

1.7

4.7

±15 ±15

2 4

450 525 750

625 700

1000

225 250 350

325 360 475

26.5

1.6

+OUT

V V

dB dB

mV mV

V V

mV mV mV

mA mA

mA mA mA

660510f

LTC6605-10

AC ELECTRICAL CHARACTERISTICS

The l denotes the speciﬁ cations which apply over the full operating temperature range, otherwise speciﬁ cations are at T

= 25°C. V+ = 3V, V– = 0V, V

otherwise noted. Filter conﬁ gured as in Figure 2, unless otherwise noted. VS is deﬁ ned as (V+ – V–). V V

)/2. V

–OUT

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

Gain Filter Gain ΔV

Phase Filter Phase ΔV

ΔGain Gain Match (Channel-to-Channel) ΔV

ΔPhase Phase Match (Channel-to-Channel) V

4V/V Gain Filter Gain in 4V/V Conﬁ guration

TC Filter Cut-Off Frequency Temperature

Noise Integrated Output Noise

HD2 2nd Harmonic Distortion

HD3 3rd Harmonic Distortion

Note 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime.

Note 2: All pins are protected by steering diodes to either supply. If any pin is driven beyond the LTC6605-10’s supply voltage, the excess input current (current in excess of what it takes to drive that pin to the supply rail) should be limited to less than 10mA.

Note 3: A heat sink may be required to keep the junction temperature below the Absolute Maximum Rating when the output is shorted indeﬁ nitely. Long-term application of output currents in excess of the Absolute Maximum Ratings may impair the life of the device.

Note 4: Both the LTC6605C and the LTC6605I are guaranteed functional over the operating temperature range –40°C to 85°C.

is deﬁ ned as (V

INCM

+IN

+ V

–IN

)/2. V

OUTDIFF

Inputs at ±IN1 Pins, ±IN4 Pins Floating Channel Separation V

Coefﬁ cient

(BW = 10kHz to 20MHz) Input Referred Noise Density (f = 1MHz) BIAS = V

Voltage Noise Density Referred to Op Amp Inputs (f = 1MHz)

Current Noise Density Referred to Op Amp Inputs (f = 1MHz)

= 5MHz; VIN = 2V

Single-Ended

P-P

Single-Ended

P-P

is deﬁ ned as (V

= ±0.125V, DC

= 0.5V

INDIFF

= ±0.125V, DC

INDIFF

= ±0.125V, DC

INDIFF

ΔVIN = ±0.125V, DC

INDIFF

BIAS = V BIAS = Floating

Figure 4, Gain = 1 Figure 4, Gain = 4 Figure 4, Gain = 5

BIAS = V BIAS = Floating

BIAS = V BIAS = Floating, R

= 0.5V = 0.5V = 0.5V = 0.5V

= 0.5V = 0.5V = 0.5V

= 1V

P-P P-P P-P P-P P-P

P-P P-P P-P

P-P

– V

+OUT

, f = 5MHz , f = 7.5MHz , f = 10MHz , f = 20MHz , f = 50MHz

, f = 5MHz , f = 7.5MHz , f = 10MHz

, f = 5MHz –96 dB

= 400Ω

LOAD

= 400Ω

LOAD

Note 5: The LTC6605C is guaranteed to meet speciﬁ ed performance from 0°C to 70°C. The LTC6605C is designed, characterized and expected to meet speciﬁ ed performance from –40°C to 85°C, but is not tested or QA sampled at these temperatures. The LTC6605I is guaranteed to meet speciﬁ ed performance from –40°C to 85°C.

Note 6: Output referred voltage offset is a function of gain. To determine output referred voltage offset, or output voltage offset drift, multiply V by the noise gain (1 + GAIN). See Figure 3.

Note 7: Input bias current is deﬁ ned as the average of the currents ﬂ owing into the noninverting and inverting inputs of the internal ampliﬁ er and is calculated from measurements made at the pins of the IC. Input offset current is deﬁ ned as the difference of the currents ﬂ owing into the noninverting and inverting inputs of the internal ampliﬁ er and is calculated from measurements made at the pins of the IC.

INCM

–OUT

). V

= V

OCM

is deﬁ ned as (V

INDIFF

= mid-supply, V

OUTCM

–0.25

–1.1

–2.35

–4.05

–11.75

–28

–0.2

–0.3

–0.35

–1.1

–1.2

11.85 12 12. 25 dB

= V+, unless

BIAS

is deﬁ ned as (V

+ V

+IN

–IN

±0.05 –0.77

–1.89

–3.5 –11.1 –25.8

0.25 –0.4

–1.45

–3

–10.55

–24.8

0 –42.5 –63.2

–81.7

±0.05 ±0.05 ±0.05 ±0.05

±0.2 ±0.2 ±0.2

0.2

0.3

0.35

1.1

1.2

–80

–260

69 μV

2.1

2.6 3

2.1

–90

–75

–106

–82

+OUT

dB dB dB dB dB dB

Deg Deg Deg Deg

dB dB dB dB

Deg Deg Deg

ppm/°C ppm/°C

RMS

nV/√Hz nV/√Hz nV/√Hz

nV/√Hz nV/√Hz

pA/√Hz pA/√Hz

dBc dBc

660510f

ELECTRICAL CHARACTERISTICS

LTC6605-10

Note 8: See the Applications Information section for a detailed discussion of input and output common mode range. Input common mode range is tested by measuring the differential DC gain with V = mid-supply, and again with V

at the input common mode range

INCM

limits listed in the Electrical Characteristics table, with ΔV

= ±0.25V,

INCM

verifying that the differential gain has not deviated from the mid-supply common mode input case by more than 0.5%, and that the common mode offset (V

) has not deviated from the mid-supply common

OSCM

mode offset by more than ±10mV. Output common mode range is tested by measuring the differential

DC gain with V

pin at the output common range limits listed in the Electrical

OCM

= mid-supply, and again with voltage set on the

OCM

Characteristics table verifying that the differential gain has not deviated from the mid-supply common mode input case by more than

0.5%, and that the common mode offset (V more than ±10mV from the mid-supply case.

Note 9: CMRR is deﬁ ned as the ratio of the change in the input common mode voltage at the internal ampliﬁ er inputs to the change in differential input referred voltage offset (V

Note 10: Power supply rejection ratio (PSRR) is deﬁ ned as the ratio of the change in supply voltage to the change in differential input referred voltage offset (V

TYPICAL PERFORMANCE CHARACTERISTICS

Supply Current vs Temperature Filter Gain vs Temperature

37.5

35.0

32.5

30.0

27.5

25.0

22.5

20.0

SUPPLY CURRENT (mA)

17.5

15.0

12.5 –60

–40 0

–20

TEMPERATURE (°C)

VS = 2.7V, BIAS = FLOAT

= 3V, BIAS = FLOAT

= 5V, BIAS = FLOAT

= 2.7V, BIAS = V

VS = 3V, BIAS = V VS = 5V, BIAS = V

= V

OCM

= MID-SUPPLY

INCM

+ + +

100

660510 G01

1.010

1.005

1.000

GAIN (V/V)

0.995

0.990 –60

VS = 3V, BIAS = V V

= V

INCM

5 RANDOM UNITS

–40 0

= MID-SUPPLY

OCM

–20

TEMPERATURE (°C)

) has not deviated by

OSCM

100

660510 G02

–3dB Frequency vs Temperature

2.5

2.0

1.5

(%)

1.0

–3dB

0.5

–0.5

–1.0

–1.5

FREQUENCY SHIFT OF f

–2.0

–2.5

–60

–40 0

BIAS = FLOAT BIAS = V

–20

TEMPERATURE (°C)

VS = 3V V

INCM

Filter Frequency Response

= V

= 1.5V

OCM

100

660510 G03

–10

–20

–30

0.1

VS = 3V V

INCM

BIAS = V BIAS PIN FLOATING

= V

OCM

FREQUENCY (MHz)

GAIN MAGNITUDE (dB)

–40

–50

= MID SUPPLY

101.0 100 1000

660514 G04

660510f

LTC6605-10

TYPICAL PERFORMANCE CHARACTERISTICS

Harmonic Distortion vs Frequency, BIAS High

–40

–50

–60

–70

–80

–90

DISTORTION (dBc) –100

–110

–120

DIFFERENTIAL INPUTS, HD2 DIFFERENTIAL INPUTS, HD3 SINGLE-ENDED INPUTS, HD2 SINGLE-ENDED INPUTS, HD3

VIN = 2V

P-P,VS

= 400Ω DIFFERENTIAL, GAIN = 1V/ V

10 100

FREQUENCY (MHz)

= 3V

Harmonic Distortion vs Input Common Mode Voltage (VS = 3V)

–40

–50

–60

–70

–80

–90

–100

DISTORTION (dBc)

–110

–120

–130

–0.5

INPUT COMMON MODE VOLTAGE (V)

VIN = 2V BIAS = 3V, f = 3MHz

= 400Ω DIFFERENTIAL, GAIN = 1V/ V

DIFFERENTIAL INPUTS, HD2 DIFFERENTIAL INPUTS, HD3 SINGLE-ENDED INPUT, HD2 SINGLE-ENDED INPUT, HD3

0.5

= 1.5V

P-P,VOCM

1.5

2 2.5

660510 G05

660510 G08

–40

–50

–60

–70

–80

–90

DISTORTION (dBc)

–100

–110

–120

Harmonic Distortion vs Frequency, BIAS Floating

–40

–50

–60

–70

–80

–90

DISTORTION (dBc)

–100

–110

–120

DIFFERENTIAL INPUTS, HD2 DIFFERENTIAL INPUTS, HD3 SINGLE-ENDED INPUTS, HD2 SINGLE-ENDED INPUTS, HD3

1 10 100

VIN = 2V

= 400Ω DIFFERENTIAL, GAIN = 1V/ V

FREQUENCY (MHz)

= 3V

P-P,VS

Harmonic Distortion vs Input

3.53

= 5V)

Common Mode Voltage (V

DIFFERENTIAL INPUTS, HD2 DIFFERENTIAL INPUTS, HD3 SINGLE-ENDED INPUT, HD2 SINGLE-ENDED INPUT, HD3

0–0.5

0.5 2.52

P-P,VOCM

1.51

= 2.5V

INPUT COMMON MODE VOLTAGE (V)

VIN = 2V BIAS = 5V, f = 3MHz

= 400Ω DIFFERENTIAL, GAIN = 1V/ V

4.5 54

660510 G09

660510 G06

Harmonic Distortion vs Input Amplitude

–40

DIFFERENTIAL INPUTS, HD2 DIFFERENTIAL INPUTS, HD3

–50

SINGLE-ENDED INPUTS, HD2

–60

SINGLE-ENDED INPUTS, HD3

–70

–80

–90

DISTORTION (dBc)

–100

–110

–120

VS = 3V, BIAS TIED TO V+,V

= 400Ω, fIN = 3MHz, GAIN = 1V/ V

LOAD

Differential Output Noise vs Frequency

1000

NOISE SPECTRAL DENSITY (nV/√Hz)

100

0.01

VS = 3V BIAS TIED TO V

OUTPUT NOISE SPECTRAL DENSITY INTEGRATED OUTPUT NOISE

0.1 1 10010 FREQUENCY (MHz)

OCM

660510 G07

= 1.5V

100

INTEGRATED NOISE (μV

RMS

)

P-P

= V

INCM

660510 G10

Channel Separation vs Frequency Overdrive Transient Response

–20

–30

–40

–50

–60

–70

–80

–90

CHANNEL SEPARATION (dB)

–100

–110

–120

0.1 10 100 1000

= 1V

= 400Ω DIFFERENTIAL

BIAS = V BIAS = FLOAT

FREQUENCY (MHz)

= 3V

P-P,VS

660510 G11

2.0

1.5

1.0

0.5

VOLTAGE (V)

–0.5

–1.0

–1.5

–2.0

VS = 3V, V BIAS = 3V, R

OCM

= 1.5V

LOAD

50ns/DIV

= 400Ω

+OUT –OUT –IN4 +IN4

660510 G12

660510f

TEST CIRCUITS

LTC6605-10

400Ω

INP

100Ω

400Ω

125Ω

–

BIASBIAS

–

INM

100Ω

400Ω

125Ω

400Ω

81.5pF

48.2pF

–

48.2pF

81.5pF

25Ω

–OUT

0.1μF

–

36k

–

660510 TC01

0.01μF

+OUT

0.1μF

–

0.1μF

OCM

25Ω

BAL

OUTCM

BAL

Figure 1. DC Test Circuit (Channel A Shown)

LTC6605-10

1μF

+IN

400Ω

100Ω

400Ω

125Ω

BIASBIAS

–

1μF

100Ω

–IN

400Ω

125Ω

400Ω

81.5pF

48.2pF

–

48.2pF

81.5pF

–OUT

0.1μF

–

36k

–

660510 TC02

0.01μF

+OUT

100Ω

OCM

100Ω

1μF

0.1μF

–

0.1μF

1μF

COILCRAFT TTWB-4-B

50Ω

Figure 2. AC Test Circuit (Channel A Shown)

660510f

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