Datasheet

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LT6552

6552f

FEATURES

DESCRIPTIO

APPLICATIO S

TYPICAL APPLICATIO

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Differential to Single-Ended Conversion

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Video Line Driver

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Automotive Displays

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RGB Amplifiers

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Coaxial Cable Drivers

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Low Voltage High Speed Signal Processing

3.3V Single Supply

Video Difference Amplifier

The LT

6552 is a video difference amplifier optimized for

low voltage single supply operation. This versatile ampli-

fier features uncommitted high input impedance (+) and

(–) inputs and can be used in differential or single-ended

configurations. A second set of inputs gives gain adjust-

ment and DC control to the differential amplifier.

On a single 3.3V supply, the input voltage range extends

from ground to 1.3V and the output swings from ground

to 2.9V while driving a 150Ω load. The LT6552 features

75MHz – 3dB bandwidth, 600V/µs slew rate, and ±70mA

output current making it ideal for driving cables directly.

The LT6552 maintains its performance for supplies from

3V to 12.6V and is fully specified at 3.3V, 5V and ±5V

supplies. The shutdown feature reduces power dissipa-

tion to less than 1mW and allows multiple amplifiers to

drive the same cable.

The LT6552 is available in the 8-lead SO package as well

as a tiny, dual fine pitch leadless package (DFN). The

device is specified over the commercial and industrial

temperature ranges.

, LTC and LT are registered trademarks of Linear Technology Corporation.

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Differential or Single-Ended Gain Block

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Wide Supply Range 3V to 12.6V

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Output Swings Rail-to-Rail

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Input Common Mode Range Includes Ground

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600V/µs Slew Rate

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–3dB Bandwidth = 75MHz, A

= ±2

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CMRR at 10MHz: >60dB

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Specified on 3.3V, 5V and ±5V Supplies

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High Output Drive: ±70mA

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Power Shutdown to 300µA

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

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Available in 8-Lead SO and

Tiny 3mm x 3mm x 0.8mm DFN Packages

LT6552

OUT

–

REF

500Ω

75Ω

CABLE

6552 TA01a

8pF

FREQUENCY (MHz)

100k

COMMON MODE REJECTION RATIO (dB)

100

1 10 100

6552 TA01b

= 5V, 0V

= 0V DC

Input Referred CMRR vs Frequency

Cable Sense Amplifier for Loop Through

Connections with DC Adjust

Summary of content (16 pages)

PAGE 1
LT6552 3.3V Single Supply Video Difference Amplifier U FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ DESCRIPTIO Differential or Single-Ended Gain Block Wide Supply Range 3V to 12.6V Output Swings Rail-to-Rail Input Common Mode Range Includes Ground 600V/µs Slew Rate –3dB Bandwidth = 75MHz, AV = ±2 CMRR at 10MHz: >60dB Specified on 3.3V, 5V and ±5V Supplies High Output Drive: ±70mA Power Shutdown to 300µA Operating Temperature Range: –40°C to 85°C Available in 8-Lead SO and Tiny 3mm x 3mm x 0.
PAGE 2
LT6552 U W W W ABSOLUTE AXI U RATI GS (Note 1) Supply Voltage (V + to V –) .................................... 12.6V Input Current (Note 2) ........................................ ±10mA Input Voltage Range ......................................... V – to V + Differential Input Voltage +Input (Pin 3) to –Input (Pin 2) ................................ ±VS Output Short-Circuit Duration (Note 3) ............ Indefinite Operating Temperature Range (Note 4) ...
PAGE 3
LT6552 3.3V ELECTRICAL CHARACTERISTICS The ● denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VS = 3.3V, 0V. Figure 1 shows the DC test circuit, VREF = VCM = 1V, VDIFF = 0V, VSHDN = V+, unless otherwise noted. RL = RF + RG = 1k. (Note 6) SYMBOL PARAMETER CONDITIONS en Input Noise Voltage Density f = 10kHz in Input Noise Current Density RIN Input Resistance CMRR Common Mode Rejection Ratio VCM = 0V to 1.
PAGE 4
LT6552 5V ELECTRICAL CHARACTERISTICS The ● denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VS = 5V, 0V; Figure 1 shows the DC test circuit, VREF = VCM = 1V, VDIFF = 0V, VSHDN = V+, unless otherwise noted. RL = RF + RG = 1k.
PAGE 5
LT6552 5V ELECTRICAL CHARACTERISTICS The ● denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VS = 5V, 0V. Figure 1 shows the DC test circuit, VREF = VCM = 1V, VDIFF = 0V, VSHDN = V+, unless otherwise noted. RL = RF + RG = 1k. (Note 6) SYMBOL PARAMETER CONDITIONS tON Turn-On Time VSHDN from 0.5V to 4.7V 250 ns tOFF Turn-Off Time VSHDN from 4.7V to 0.5V 450 ns 0.25 µA Shutdown Output Leakage Current VSHDN = 0.
PAGE 6
LT6552 ±5V ELECTRICAL CHARACTERISTICS The ● denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VS = ±5V. Figure 2 shows the DC test circuit, VREF = VCM = 0V, VDIFF = 0V, VSHDN = V +, unless otherwise noted. RL = RF + RG = 1k. (Note 6) SYMBOL PARAMETER CONDITIONS Shutdown Pin Current VSHDN = –4.5V VSHDN = 4.7V tON Turn-On Time VSHDN from – 4.5V to 4.7V tOFF Turn-Off Time VSHDN from 4.7V to –4.
PAGE 7
LT6552 U W TYPICAL PERFOR A CE CHARACTERISTICS Supply Current vs Supply Voltage –10 18 14 INPUT BIAS CURRENT (µA) SUPPLY CURRENT (mA) –12 TA = 125°C TA = –55°C 12 TA = 25°C 10 8 6 4 –4 VS = 5V, 0V VCM = 1V –14 –16 –18 –20 –22 2 2 0 6 8 10 4 TOTAL SUPPLY VOLTAGE (V) 12 50 25 75 0 TEMPERATURE (°C) 100 TA = 125°C –12 TA = 25°C –14 –16 TA = –55°C –18 –20 Output Saturation Voltage vs Load Current (Output High) Output Saturation Voltage vs Load Current (Output Low) 1 OUTPUT LOW SATURATI
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LT6552 U W TYPICAL PERFOR A CE CHARACTERISTICS Input Noise Voltage Density vs Frequency Open-Loop Gain 225 400 300 200 100 RL = 1k RL = 150Ω –200 –300 –400 150 125 100 75 50 25 100 –500 –5 –4 –3 –2 –1 0 1 2 3 OUTPUT VOLTAGE (V) 4 5 1k 10k FREQUENCY (Hz) Closed-Loop Voltage Gain vs Frequency 6.2 CLOSED-LOOP VOLTAGE GAIN (dB) 7 6 3.3V 5 VIN 4 VDC 3 2 3 2 7 + – LT6552 1 REF 8 FB 4 6 RF 500Ω VOUT RL 150Ω RG 500Ω 1 0 100k 1M 10M FREQUENCY (Hz) 6.1 6.0 5.9 5.
PAGE 9
LT6552 U W TYPICAL PERFOR A CE CHARACTERISTICS RL = 150Ω TA = 25°C VOUT = –3V TO 3V VS = ±5V Output Impedance vs Frequency Slew Rate vs Temperature 550 VS = ±5V AV = 2 RL = 150Ω AV = 2 1 0.1 VS = 5V, 0V VOUT = 0.5V T0 3.5V 400 10M 1M FALLING 300 VS = 3.3V, 0V VOUT = 0.5V T0 2.5V RISING 100 VS = 3.
PAGE 10
LT6552 U W TYPICAL PERFOR A CE CHARACTERISTICS Large Signal Response, VS = 5V, 0V 0V AV = 2 CF = 5pF CL = 10pF RF = RG = 500Ω RL = 150Ω 50ns/DIV Small Signal Response, VS = 5V, 0V 50mV/DIV 1V/DIV 500mV/DIV Large Signal Response, VS = ±5V 0V 6552 G27 AV = 2 CF = 5pF CL = 10pF RF = RG = 500Ω RL = 150Ω Small Signal Response, VS = 5V, 0V 50ns/DIV 6552 G28 AV = 1 CL = 10pF RL = 150Ω Shutdown Response 50ns/DIV 6552 G29 Output Overdrive Recovery VSHDN 2V/DIV 50mV/DIV 2.
PAGE 11
LT6552 U U W U APPLICATIO S I FOR ATIO The LT6552 is a video difference amplifier with two pairs of high impedance inputs. The primary purpose of the LT6552 is to convert high frequency differential signals into a single-ended output, while rejecting any common mode noise. In the simplest configuration, one pair of inputs is connected to the incoming differential signal, while the other pair of inputs is used to set amplifier gain and DC level.
PAGE 12
LT6552 U W U U APPLICATIO S I FOR ATIO Amplifier Characteristics The current generated through R1 or R2, divided by the capacitor CM, determines the slew rate. Note that this current, and hence the slew rate, are proportional to the magnitude of the input step. The input step equals the output step divided by the closed-loop gain. The highest slew rates are therefore obtained in the lowest gain configurations.
PAGE 13
LT6552 U W U U APPLICATIO S I FOR ATIO Layout and Passive Components Operating with Low Closed-Loop Gains With a bandwidth of 75MHz and a slew rate of 600V/µs, the LT6552 requires special attention to board layout and supply bypassing. Use a ground plane, short lead lengths and RF quality low ESR supply bypass capacitors. The positive supply pin should be bypassed with a small capacitor (typically 0.1µF) within 1 inch of the pin. When driving loads greater than 10mA, an additional 4.
PAGE 14
LT6552 U W U U APPLICATIO S I FOR ATIO SHDN Pin The LT6552 includes a shutdown feature that disables the part, reducing quiescent current and making the output high impedance. The part can be shutdown by bringing the SHDN pin within 0.5V of V–. When shutdown the supply current is typically 400µA and the output leakage current is 0.25µA (V– ≤ VOUT ≤ V+).
PAGE 15
LT6552 U PACKAGE DESCRIPTIO S8 Package 8-Lead Plastic Small Outline (Narrow .150 Inch) (Reference LTC DWG # 05-08-1610) .189 – .197 (4.801 – 5.004) NOTE 3 .045 ±.005 .050 BSC 8 .245 MIN 7 6 5 .160 ±.005 .150 – .157 (3.810 – 3.988) NOTE 3 .228 – .244 (5.791 – 6.197) .030 ±.005 TYP 1 RECOMMENDED SOLDER PAD LAYOUT .010 – .020 × 45° (0.254 – 0.508) .008 – .010 (0.203 – 0.254) 3 4 .053 – .069 (1.346 – 1.752) .004 – .010 (0.101 – 0.254) 0°– 8° TYP .016 – .050 (0.406 – 1.270) NOTE: 1.
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LT6552 U TYPICAL APPLICATIO YPBPR to RGB Video Converter +3V +3V 499Ω 499Ω 499Ω 499Ω 5.6pF 8.2pF 8 8 1 2 3 FB 7 REF – + 1 LT6552 6 2 3 5 4 FB 7 REF – + LT6552 6 75Ω G 5 4 75Ω SD SD –3V –3V +3V 499Ω 909Ω Y 2.2pF 8 1 PR 21.5Ω 53.6Ω 2 21.5Ω 3 FB 7 REF – + 11.3Ω LT6552 6 75Ω R 5 4 75Ω SD –3V +3V 42.2Ω 499Ω 1.3k 1pF 8 1 PB 2 49.9Ω 25.5Ω 3 FB 7 REF – + LT6552 6 75Ω B 5 4 75Ω SD –3V R = Y + 1.4 • PR G = Y – 0.34 • PB – 0.71 • PR B = Y + 1.