LT6557IDHC

LT6557 500MHz, 2200V/µs Gain of 2, Single Supply Triple Video Amplifier with Input Bias Control FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ DESCRIPTION The LT®6557 is a high speed triple video amplifier with an internal fixed gain of 2 and a programmable DC input bias voltage. This amplifier features a 400MHz 2VP-P signal bandwidth, 2200V/µs slew rate and a unique ability to drive heavy output loads to 0.8V of the supply rails, making the LT6557 ideal for a single 5V supply, wideband video application. With just one resistor, the inputs of all three amplifiers can be programmed to a common voltage level, simplifying and reducing the need for external circuitry in the AC-coupled applications. Without the programmable resistor, the input bias circuit becomes inactive, allowing the use of an external clamp circuit or direct coupled input. The LT6557 has separate power supply and ground pins for each amplifier to improve channel separation and to ease power supply bypassing. The LT6557 provides uncompromised performance in many high speed applications where a low voltage, single supply is required. The LT6557 is available in 16-lead SSOP and 5mm × 3mm DFN packages. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. –3dB Small-Signal Bandwidth: 500MHz –3dB 2VP-P Large-Signal Bandwidth: 400MHz Slew Rate: 2200V/µs Fixed Gain of 2, No External Resistors Required AC Coupling with Programmable DC Input Bias Output Swings to 0.8V of Supply Rails Full Video Swing with 5V Single Supply Diff Gain: 0.02% Diff Phase: 0.05° Enable/Shutdown Pin High Output Current: ±100mA Supply Range: 3V to 7.5V Operating Temperature Range: –40°C to 85°C Available in 16-Lead SSOP and 5mm × 3mm DFN Packages APPLICATIONS ■ ■ ■ ■ LCD Video Projectors RGB HD Video Amplifiers Coaxial Cable Drivers Low Supply ADC Drivers TYPICAL APPLICATION AC-Coupled Triple Video Driver EN 22µF IN R 75Ω GND IN R LT6557 BCV V+ OUT R 500Ω 5V 75Ω 220µF 412Ω Fast Large-Signal Transient Response GND R 500Ω + – V+ R 75Ω 5V 22µF IN G 75Ω IN G GND G 500Ω + – OUT G 500Ω 75Ω 220µF V+ G 75Ω 5V 22µF IN B 75Ω IN B GND B 500Ω + – OUT B 500Ω 75Ω 220µF V+ B 75Ω 5V 6557 TA01a 6557fa 1 LT6557 ABSOLUTE MAXIMUM RATINGS (Note 1) Total Supply Voltage (VS+ to GND) ...........................7.5V Input Current........................................................±10mA Output Current (Note 2) .......................................±70mA Output Short-Circuit Duration (Note 2) ............ Indefinite Operating Temperature Range (Note 3) ... –40°C to 85°C Specified Temperature Range (Note 4) .... –40°C to 85°C Junction Temperature SSOP ................................................................ 150°C DFN ................................................................... 125°C Storage Temperature Range SSOP ................................................. –65°C to 150°C DFN.................................................... –65°C to 125°C Lead Temperature (Soldering, 10 sec) SSOP ................................................................ 300°C PACKAGE/ORDER INFORMATION TOP VIEW TOP VIEW EN GND IN R GND R IN G GND G IN B GND B 1 2 3 4 5 6 7 8 G = +2 G = +2 G = +2 16 BCV 15 V+ 14 OUT R 13 V+ R 12 OUT G 11 V+ G 10 OUT B 9 V+ B EN GND IN R GND R IN G GND G IN B GND B 1 2 3 4 5 6 7 8 G = +2 G = +2 17 G = +2 16 BCV 15 V+ 14 OUT R 13 V+ R 12 OUT G 11 V+ G 10 OUT B 9 V+ B GN PACKAGE 16-LEAD PLASTIC SSOP TJMAX = 150°C, θJA = 110°C/W DHC PACKAGE 16-LEAD (5mm × 3mm) PLASTIC DFN TJMAX = 125°C, θJA = 40°C/W EXPOSED PAD (PIN 17) IS GND, MUST BE SOLDERED TO PCB ORDER PART NUMBER LT6557CGN LT6557IGN GN PART MARKING 6557 6557I ORDER PART NUMBER LT6557CDHC LT6557IDHC DHC PART MARKING* 6557 6557 Order Options Tape and Reel: Add #TR Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF Lead Free Part Marking: http://www.linear.com/leadfree/ Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. The ● denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VS = 5V, RL = 150Ω to VS/2, VEN = 0.4V, RBCV = open, unless otherwise noted. SYMBOL VOS IIN RIN CIN PARAMETER Input Offset Voltage Input Current Input Resistance Input Capacitance CONDITIONS VIN = 1.25V VIN = 1.25V VIN = 0.75V to 1.75V, BCV (Pin 6) Open f = 1MHz ● ● ● ELECTRICAL CHARACTERISTICS MIN TYP 12 15 35 45 MAX 40 50 70 100 UNITS mV mV µA µA kΩ kΩ pF 6557fa 90 50 200 150 1.5 2 LT6557 The ● denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VS = 5V, RL = 150Ω to VS/2, VEN = 0.4V, RBCV = open, unless otherwise noted. SYMBOL AV ERR AV MATCH VIN(DC) PSRR VOL VOH IS PARAMETER Gain Error Gain Match Between Channels Input Voltage Bias Power Supply Rejection Ratio Output Voltage Swing Low ● ELECTRICAL CHARACTERISTICS CONDITIONS VIN = 0.75V to 1.75V VIN = 0.75V to 1.75V RBCV = 348Ω VS = 4V to 6V, VIN = 1.25V ● ● ● ● MIN TYP ±0.5 ±0.5 ±0.4 ±0.4 MAX ±2.5 ±3.0 ±2.75 ±3.25 1.5 1.7 UNITS % % % % V V dB dB 1.0 0.8 42 38 1.25 1.10 50 47 0.8 0.9 0.9 1.0 V V V V Output Voltage Swing High ● 4.1 4.0 4.2 4.1 22.5 25.0 10 10 25 29 450 1000 Supply Current per Amplifier Total Supply Current (Disabled) VEN = 0.4V, RL = ∞, Includes IS of V+ (Pin 15) VEN = Open, RL = ∞ VEN = 0.4V ● ● ● ● mA mA µA µA µA µA mA mA V/µs MHz MHz MHz MHz dB dB ns ns ps % Deg dBc dBc IEN ISC SR –3dB BW 0.1dB BW FPBW XTalk tS tr, tf ΔG ΔΦ HD2 HD3 Enable Pin Current Short-Circuit Current Slew Rate –3dB Bandwidth Gain Flatness ±0.1dB Bandwidth Full Power Bandwidth All Hostile Crosstalk Settling Time Rise Time, Fall Time Differential Gain Differential Phase 2nd Harmonic Distortion 3rd Harmonic Distortion –250 –300 ±70 ±40 1400 –125 –150 ±100 ±90 2200 400 500 120 VOUT = 1.25V to 3.75V (Note 5) VOUT = 2VP-P VOUT = 0.2VP-P VOUT = 2VP-P VOUT = 2VP-P (Note 6) f = 10MHz, VOUT = 2VP-P f = 100MHz, VOUT = 2VP-P To 1%, VOUT = 1.5V to 3.5V To 0.1% 10% to 90%, VOUT = 1.5V to 3.5V NTSC Signal NTSC Signal f = 10MHz, VOUT = 2VP-P f = 10MHz, VOUT = 2VP-P 220 350 –80 –55 4 7 875 0.02 0.05 –68 –75 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: A heat sink may be required to keep the junction temperature below the Absolute Maximum Rating. Note 3: The LT6557C is guaranteed functional over the temperature range of –40°C and 85°C. Note 4: The LT6557C is guaranteed to meet specified performance from 0°C to 70°C. The LT6557C is designed, characterized and expected to meet specified performance from –40°C to 85°C but is not tested or QA sampled at these temperatures.The LT6557I is guaranteed to meet specified performance from –40°C to 85°C. Note 5: Slew rate is 100% production tested on the R channel and measured on the rising edge of the output signal. The slew rate of the falling edge and of the G and B channels is guaranteed through design and characterization. Note 6: Large-signal bandwidth is calculated from slew rate: FPBW = SR/(π • VP-P) 6557fa 3 LT6557 TYPICAL PERFORMANCE CHARACTERISTICS Gain Error Distribution Gain Error Matching Distribution Voltage Gain vs Temperature Supply Current per Ampifier vs Supply Voltage 50 45 40 SUPPLY CURRENT (mA) 35 30 25 20 15 10 5 0 0 1 2 6 3 4 5 SUPPLY VOLTAGE (V) 7 8 VOUT = VS/2 Supply Current per Ampifier vs Temperature Supply Current per Ampifier vs EN Voltage 6557 G04 EN Pin Current vs EN Pin Voltage Input Referred Offset Voltage vs Temperature Input Bias Current vs Input Voltage 6557fa 4 LT6557 TYPICAL PERFORMANCE CHARACTERISTICS Output Voltage vs Input Voltage Output Voltage Swing vs Load Current (Output High) Output Voltage Swing vs Load Current (Output Low) Input Bias Voltage vs Resistance at BCV Pin Input Bias Voltage vs Temperature Bias Control Voltage vs Temperature Frequency Response Frequency Response of Three Amplifiers Gain Flatness vs Frequency 6557fa 5 LT6557 TYPICAL PERFORMANCE CHARACTERISTICS Frequency Response with Capacitive Loads Large-Signal Group Delay Crosstalk Between Amplifiers vs Frequency Output Impedance vs Frequency Input Impedance vs Frequency PSRR vs Frequency Distortion vs Frequency Distortion vs Frequency Input Referred Noise Spectral Density 6557fa 6 LT6557 TYPICAL PERFORMANCE CHARACTERISTICS Overdriven Output Recovery 5 VIN VIN = 0.5V/DIV, VOUT = 1V/DIV 4 VOUT 5 4 3 VOLTAGE (V) 3 2 VOUT 1 1 VS = 5V VIN = 2.4VP-P RL = 1509 0 25 50 75 100 125 150 175 200 225 250 TIME (ns) 6557 G28 Enable/Disable Response 6 VEN(DISABLE) VS = 5V VOUT = 2VP-P AC COUPLED RL = 150W 2 0 VEN(ENABLE) –1 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 TIME (ms) 6557 G29 0 Large-Signal Transient Response 2.65 Small-Signal Transient Response VS = 5V VIN = 50mVP-P RL = 1509 2.60 OUTPUT (V) 2.55 2.50 2.45 0 2 4 6 8 10 12 14 16 18 20 22 24 TIME (ns) 6557 G31 PIN FUNCTIONS EN (Pin 1): Enable Control Pin. The part is enabled when this pin is pulled low. An internal pull-up resistor of 40k will turn the part off if this pin is unconnected. GND (Pin 2): Ground Reference for Enable Pin (Pin 1) and Bias Control Voltage Pin (Pin 16). This pin must be connected externally to ground. IN R (Pin 3): Red Channel Input. This pin has a nominal impedance of 200kΩ with input bias circuit inactive, Pin 16 open. GND R (Pin 4): Ground of Red Channel Amplifier. This pin is not internally connected to other ground pins and must be connected externally to ground. IN G (Pin 5): Green Channel Input. This pin has a nominal impedance of 200kΩ with input bias circuit inactive, Pin 16 open. GND G (Pin 6): Ground of Green Channel Amplifier. This pin is not internally connected to other ground pins and must be connected externally to ground. IN B (Pin 7): Blue Channel Input. This pin has a nominal impedance of 200kΩ with input bias circuit inactive, Pin 16 open. GND B (Pin 8): Ground of Blue Channel Amplifier. This pin is not internally connected to other ground pins and must be connected externally to ground. 6557fa 7 LT6557 PIN FUNCTIONS V+ B (Pin 9): Positive Supply Voltage of Blue Channel Amplifier. This pin is not internally connected to other supply voltage pins and must be externally connected to the supply voltage bus with proper bypassing for best performance, see Power Supply Considerations. OUT B (Pin 10): Blue Channel Output. V+ G (Pin 11): Positive Supply Voltage of Green Channel Amplifier. This pin is not internally connected to other supply voltage pins and must be externally connected to the supply voltage bus with proper bypassing for best performance, see Power Supply Considerations. OUT G (Pin 12): Green Channel Output. V+ R (Pin 13): Positive Supply Voltage of Red Channel Amplifier. This pin is not internally connected to other supply voltage pins and must be externally connected to the supply voltage bus with proper bypassing for best performance, see Power Supply Considerations. OUT R (Pin 14): Red Channel Output. V+ (Pin 15): Positive Supply Voltage of Control Circuitry. This pin is not internally connected to other supply voltage pins and must be externally connected to supply voltage bus with proper bypassing for best performance, see Power Supply Considerations. BCV (Pin 16): Bias Control Voltage. A resistor connected between Pin 16 and Pin 2 (GND) will generate a DC voltage bias at the inputs of the three amplifiers for AC coupling application, see Programmable Input Bias. Exposed Pad (Pin 17, DFN Package): Ground. This pad must be soldered to PCB and is internally connected to GND (Pin 2). APPLICATIONS INFORMATION Power Supply Considerations The LT6557 is optimized to provide full video signal swing output when operated from a standard 5V single supply. Due to the supply current involved in ultrahigh slew rate amplifiers like the LT6557, selection of the lowest workable supply voltage is recommended to minimize heat generation and simplify thermal management. Temperature rise at the internal devices (TJ) must be kept below 150°C (SSOP package) or 125°C (DFN package), and can be estimated from the ambient temperature (TA) and power dissipation (PD) as follows: TJ = TA + PD • 40°C/W for DFN package or TJ = TA + PD • 110°C/W for SSOP package where PD = (IS + 0.5 • IO) • VS(TOTAL) The latter equation assumes (conservatively) that the output swing is small relative to the supply and RMS load current (IO) is bidirectional (as with AC coupling). The grounds are separately pinned for each amplifier to minimize crosstalk. Operation from split supplies can be accomplished by connecting the LT6557 ground pins to the negative rail. Since the amplifier gain is referenced to its ground pins, the actual signals are referenced to the negative rail, in this case, and DC coupled applications need to take this into consideration. With dual supplies, recommended voltages range from nominal ±2.5V to ±3.3V. The ultrahigh frequency (UHF) operating range of the LT6557 requires that careful printed circuit layout practices be followed to obtain maximum performance. Trace lengths between power pins and bypass capacitors should be minimized (