LT3694EUFD#PBF Linear Technology, LT3694EUFD#PBF Datasheet

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... SYNC pin while the LT3694-1 offers a CLKOUT pin allowing other DC/DC converters to synchronize to the LT3694-1 clock. L, LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. BST 0.22μ ...

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... UFD PACKAGE 28-LEAD (4mm 5mm) PLASTIC QFN θ = 34°C/W JA EXPOSED PAD (PIN 29) IS GND, MUST BE SOLDERED TO PCB LT3694-1 PINOUT IS SHOWN IN PARENTHESIS ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL LT3694EUFD#PBF LT3694EUFD#TRPBF LT3694IUFD#PBF LT3694IUFD#TRPBF LT3694EFE#PBF LT3694EFE#TRPBF LT3694IFE#PBF LT3694IFE#TRPBF LT3694-1EUFD#PBF LT3694-1EUFD#TRPBF LT3694-1IUFD#PBF LT3694-1IUFD#TRPBF ...

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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T PARAMETER V Internal Undervoltage Lockout IN Overvoltage Shutdown Threshold Input Quiescent Current Bias Quiescent Current Shutdown Current EN/UVLO Threshold, Bias On EN/UVLO Threshold, Switching On Reference Voltage Line Regulation Switching Frequency ...

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LT3694/LT3694-1 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T PARAMETER LDO Regulator Feedback Pin Voltage Feedback Pin Bias Current Error Amplifier Voltage Gain TRK/SS Pull-Up Current TRK/SS Threshold to Shut Down LDO Line Regulation Load Regulation Base Drive Current ...

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TYPICAL PERFORMANCE CHARACTERISTICS Efficiency OUT 100 f = 800kHz 6. 12V 36V (A) OUT 36941 G01 ...

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LT3694/LT3694-1 TYPICAL PERFORMANCE CHARACTERISTICS I vs Temperature TRK/SS 4.0 3.5 3.0 2.5 2.0 – 100 TEMPERATURE (°C) 36941 G10 LDO Current Limit vs Temperature –1 –2 –3 –4 –5 – ...

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PIN FUNCTIONS (FE/UFD) V (Pin 1/Pins 27, 28): The V pin supplies power to the IN IN internal switch of the 2.6A regulator and to the LT3694’s internal reference and start-up circuitry. This pin must be locally bypassed. EN/UVLO (Pin ...

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LT3694/LT3694-1 BLOCK DIAGRAM BIAS OUT1 EN/UVLO 0.5V 1.2V 60mV OUT1 – R LIM2 LIM2 + DRV2 3μA TRK/SS2 OUT2 + SD + 0.75V FB2 – 0.68V SLOPE COMP CLK GND Figure 1. ...

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OPERATION Unless specifically noted, this data sheet refers to both the LT3694 and the LT3694-1 generically as the LT3694. The LT3694 is a constant-frequency, current mode, buck regulator with an internal power switch plus two low dropout linear regulator controllers. ...

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LT3694/LT3694-1 APPLICATIONS INFORMATION STEP DOWN SWITCHING REGULATOR Feedback Resistor Network The output voltage is programmed with a resistor divider (refer to the Block Diagram in Figure 1) between the output and the FB pin. Choose the resistors according to: ⎛ ...

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APPLICATIONS INFORMATION t = 140ns the frequency at which the mini- OFF(MIN) MAX1 mum duty cycle is exceeded. The regulator will skip ON pulses in order to reduce the overall duty cycle at frequencies above ...

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LT3694/LT3694-1 APPLICATIONS INFORMATION where f is the switching frequency of the LT3694 and L is the value of the inductor. The peak inductor and switch current is: Δ SWPK LPK OUT 2 To maintain output ...

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... If the LT3694 circuit is plugged into a live supply, the input voltage can ring to twice its nominal value, possibly exceeding the LT3694’s maximum input voltage rating. See Linear Technology Application Note 88 for more details. Output Capacitor Selection The output capacitor filters the inductor current to generate an output with low voltage ripple ...

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LT3694/LT3694-1 APPLICATIONS INFORMATION Diode Selection The catch diode (D1 from Figure 1) conducts current only during switch off time. Average forward current in normal operation can be calculated from: − OUT I • D(AVG) OUT V ...

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APPLICATIONS INFORMATION The power section, consisting of the modulator, power switch and inductor, is modeled as a transconductance amplifier generating an output current proportional to the voltage at the V pin. Note that the output capacitor C1 integrates this current, ...

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LT3694/LT3694-1 APPLICATIONS INFORMATION operating voltage of an LT3694 application is limited by the minimum input voltage (4V) and by the maximum duty cycle as outlined in a previous section. For proper start-up, the minimum input voltage is also limited by ...

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APPLICATIONS INFORMATION Once EN/UVLO climbs above the first threshold, the inter- nal circuitry of the LT3694 is turned on but the switching regulator and LDOs remain shut off. A 2μA current sink on the EN/UVLO pin is activated to provide ...

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LT3694/LT3694-1 APPLICATIONS INFORMATION The LDO may be shut down unused by pulling the FB pin up with a resistor that will source at least 30μA. The FB pin will clamp at about 1.25V and the LDO will ...

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APPLICATIONS INFORMATION If the current feeding the collector of the NPN through the sense resistor comes from a supply that is not connected to BIAS, the current limit cannot be used and the LIM pin must be connected to BIAS ...

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... Keep in mind other heat sources—such as the catch diode, inductor and LDO pass transistors. Other Linear Technology Publications Application Notes 19, 35 and 44 contain more detailed descriptions and design information for buck regulators and other switching regulators. The LT1376 data sheet has a more extensive discussion of output ripple, loop compensation and stability testing ...

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APPLICATIONS INFORMATION OUT2 THERMAL VIAS TO GROUND PLANE SIGNAL VIAS TO INNER LAYERS Figure 9. A Good PCB Layout Ensures Proper, Low EMI Operation PCB BOTTOM SIDE IS A SOLID GROUND PLANE ...

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LT3694/LT3694-1 TYPICAL APPLICATIONS Automotive Input Range (6V to 16V) to 3.3V, 2.5V, 1. 16V TRANSIENT TO 70V UVLO 5.8V 1nF 0.1Ω OUT1 ZXTN25012EZ OUT2 2.5V 450mA 2.2μF 22 100k 4.7μF 26.7k V EN/UVLO BIAS BST IN ...

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TYPICAL APPLICATIONS Wide Input Range to (6.3V to 36V) to 5V, 3.3V, 2.5V With Independent On/Off Control of the LDOs V IN 6.3V TO 36V TRANSIENT TO 70V ENABLE ENLD02 ENLD03 1nF 1nF 0.1Ω OUT1 ZXTN25020DG OUT2 2.5V 450mA 2.2μF ...

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LT3694/LT3694-1 TYPICAL APPLICATIONS 36V TRANSIENT TO 70V UVLO 5.8V ZXTN25020DG OUT2 3.3V THE LDO OUTPUT CURRENT CAPABILITY IS LIMITED BY THE POWER DISSIPATION OF THE NPN PASS TRANSISTORS 24 Wide Input Range (6V to 36V) to ...

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PACKAGE DESCRIPTION 4.50 0.05 3.10 0.05 2.50 REF 2.65 0.05 0.25 0.05 0.50 BSC RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED PIN 1 TOP MARK (NOTE 6) 5.00 0.10 (2 SIDES) NOTE: ...

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LT3694/LT3694-1 PACKAGE DESCRIPTION 6.60 ±0.10 4.50 ±0.10 SEE NOTE 4 RECOMMENDED SOLDER PAD LAYOUT 4.30 – 4.50* (.169 – .177) 0.09 – 0.20 0.50 – 0.75 (.0035 – .0079) (.020 – .030) NOTE: 1. CONTROLLING DIMENSION: MILLIMETERS 2. DIMENSIONS ARE ...

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... Corrected the Pin Configuration drawing and Package Description for the TSSOP package. Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...

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... TA05 = 0.78V 70μA, I < 1μA, OUT(MIN 0.8V 2.5mA, I < 10μA, OUT(MIN 0.8V 7mA, I < 1μA, OUT(MIN 0.78V 70μA, I < 1μA, OUT(MIN 1.21V 2μA, OUT(MIN 0.8V 85μA, OUT(MIN 0111 REV A • PRINTED IN USA © LINEAR TECHNOLOGY CORPORA TION 2010 36941fa ...