LTC3816IFE#TRPBF Linear Technology, LTC3816IFE#TRPBF Datasheet

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... PWRGD and overtemperature flags. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents, including 5408150, 5055767, 5481178, 6580258. V ...

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LTC3816 absoluTe MaxiMuM raTings Input Supply Voltage (V ) ......................... –0.3V to 40V IN Topside Driver Voltage (BOOST) ................ –0.3V to 46V Switch Voltage (SW) ..................................... –5V to 40V INTV , EXTV , (BOOST-SW) .................. –0. ...

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... LEAD FREE FINISH TAPE AND REEL LTC3816EFE#PBF LTC3816EFE#TRPBF LTC3816IFE#PBF LTC3816IFE#TRPBF LTC3816EUHF#PBF LTC3816EUHF#TRPBF LTC3816IUHF#PBF LTC3816IUHF#TRPBF Consult LTC Marketing for parts specified with wider operating junction temperature ranges. *The temperature grade is identified by a label on the shipping container. For more information on lead free part marking, go to: ...

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LTC3816 elecTrical characTerisTics junction temperature range, otherwise specifications are at T otherwise noted. (Notes 2, 3) SYMBOL PARAMETER V Core Supply Start-Up Voltage BOOT V Overvoltage Fault Threshold OVF I SS Pull-Up Current SS I CSLEW Pull-Up Current CSLEW I ...

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T otherwise noted. (Notes 2, 3) SYMBOL PARAMETER VID, DPRSLPVR, LFF Parameters V VID Input Low Threshold IL(VID) V VID Input High Threshold IH(VID) I VID Input Leakage Current VID V ...

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LTC3816 Typical perForMance characTerisTics Efficiency vs Load Current 100 V = 12V 400kHz IN OSC 0.75V CC(CORE) EXTVCC LAST PAGE CIRCUIT PULSE-SKIPPING 50 MODE 40 30 FORCED CONTINUOUS 20 ...

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Typical perForMance characTerisTics Load Regulation vs Temperature 0 –10 5A LOAD –20 10A LOAD –30 –40 –50 20A LOAD –60 –70 – 12V 400kHz IN OSC V = 0V, AVP = –3mV/A –90 EXTVCC L = ...

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LTC3816 Typical perForMance characTerisTics Start- BOOT V CC(CORE) 200mV/DIV CLKEN# 5V/DIV PWRGD 5V/DIV VR ON 5V/DIV 3816 G16 V = 12V 100µs/DIV IN IMVP6 CONFIGURATION C = 470pF SS VID = 0.75V NO LOAD Momentary Overcurrent, 45µs I ...

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Typical perForMance characTerisTics Duty Cycle vs V without Line COMP Feedforward 100 V = 12V 400kHz OSC LFF = 1.8 1.0 1.2 1.4 1.6 2.0 2.2 ...

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LTC3816 Typical perForMance characTerisTics EXTV Switchover Voltage CC vs Temperature 4.8 4.7 4.6 EXTV RAMPS HIGH CC 4.5 4.4 4.3 4.2 EXTV RAMPS LOW CC 4.1 4.0 3.9 –50 – 100 TEMPERATURE (°C) 3816 G34 I ...

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FuncTions (eTSSOP/QFN) I (Pin 1/Pin 36): Current Sense Negative Input. Con- SENN nect this pin to the negative terminal of the current sense resistor or the negative terminal of the inductor DCR lowpass filter. I (Pin 2/Pin 37): Inductor ...

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LTC3816 pin FuncTions (eTSSOP/QFN) CSLEW (Pin 15/Pin 12): VID DAC Slew Rate Control. CSLEW is internally pulled current source. Add a capacitor to program the VID DAC transition slew rate. If slow slew rate is selected, a ...

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FuncTions (eTSSOP/QFN) SW (Pin 32/Pin 29): Switching Node. Connect SW to the source of the upper power MOSFET and to the negative terminal of the BOOST pin decoupling capacitor. PWRGD (Pin 33/Pin 30): Open-Drain Power Good Out- put/Power Bad ...

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LTC3816 FuncTional DiagraM 3.3V 3.3V 1.1V 1.9k 1.9k 56 PWRGD CLKEN# VRTT# EN CLK PWRGD + VID0-VID6 BANDGAP – CHIP TSD 10µA/40µA DAC CSLEW C SLEW INTV CC 1µA MODE/SYNC 10µA RFREQ PWRGD R FREQ 1µ ...

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Funtional Diagram) Table 1. IMVP-6/IMVP-6.5 VID Output Voltage Programming VID6 VID5 VID4 VID3 VID2 VID1 ...

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LTC3816 operaTion (Refer to Funtional Diagram) The LTC3816 is a constant frequency, voltage mode DC/DC step-down controller that complies with the Intel IMVP-6/ IMVP-6.5 specifications. The 7-bit VID code programs the switcher output voltage as specified in Table 1. Figure ...

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LDO, INTV /EXTV POWER SUPPLY CC CC The LTC3816 is designed to operate with a wide range of V input voltages. The IC includes a 5.2V LDO to power IN the driver and control circuits. The LDO output, ...

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LTC3816 applicaTions inForMaTion down mode by pulling the VR pin below 0.65V. In the ON shutdown mode, the internal circuitry and the INTV regulator are off and the supply current drops well below 100µA. When the VR pin voltage is ...

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Figure 4 shows a real current sensing resistor which can be modeled SENSE with an ideal resistance series with its parasitic SEN ESL. As shown in Figure 4, the ...

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LTC3816 applicaTions inForMaTion Note that the value of R must account for its temperature DCR coefficient, which is approximately 0.39%/°C. The current limit architecture of the LTC3816 allows short durations of instantaneous overload. Upon power-up, the current limit threshold is ...

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This current limit condition persists until the fault condition disappears or the controller detects a low output voltage fault and forces the switcher output to latch off. Once the output voltage is ...

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LTC3816 applicaTions inForMaTion where A is the AVP gain with sense resistor con- AVP(SR) figuration and A is the sense resistor gain: G(SR • R and A AVP SEN ESL ...

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NTC compensation network. To determine the compo- nent values, first, select the NTC with room temperature resistance approximately equal to R smallest temperature coefficient (β constant in the NTC data sheet. Using an NTC with a higher ...

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LTC3816 applicaTions inForMaTion resistance (0.39%/°C) and produces a near perfect AVP slope across temperature – A • OUT DAC AVP(DCRP) L DAC where • R and A AVP DCRP ( ) ...

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LC Filter The external inductor and output capacitor combination causes a second order LC roll-off at the output with 180° of phase shift. At higher frequencies, the reactance of the output capacitor approaches its ESR, and the roll-off ...

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LTC3816 applicaTions inForMaTion SERVO V FB – + 1.3V LTC3816 + DAMP – Figure 14a. LTC3816 Frequency Compensation with Sense Resistor Configuration SERVO V FB – + 1.3V LTC3816 ...

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Select f = feedback crossover frequency = C where N is between 5 and 10 the feedback loop crossover frequency, f gain is unity, therefore the error amplifier gain is COMP = V ...

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LTC3816 applicaTions inForMaTion V OUT 100mV/DIV VID5 1V/DIV DPRSLPVR 5V/DIV V = 12V 0.1ms/DIV 0.75V TO 1.15V OUT C = 47pF SLEW IMVP-6 CONFIGURATION Figure 15. Programmable VID Slew Rate the controller reduces the I pull-up current ...

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Placing a resistor between RFREQ and GND creates a potential given by the follow- ing equation • R RFREQ RFREQ RFREQ where I = 10µA and allows the oscillator free-running RFREQ ...

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LTC3816 applicaTions inForMaTion output voltage is ramped down, the controller continues to hold the regulator output and PWRGD low until the VR pin toggles or the input supply resets. ON During a VID transition, the power good comparators are masked ...

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POWER MOSFET AND SCHOTTKY DIODE SELECTION The LTC3816 requires two external N-channel power MOSFETs: One for the top (main) switch and one (or more) for the bottom (synchronous) switch. The peak-to-peak MOSFET gate drive levels are set by ...

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LTC3816 applicaTions inForMaTion 2 Both MOSFETs have I R losses while the topside N-channel equation includes an additional term for transition losses, which are highest at the highest input voltage. The number, type and on-resistance of all MOSFETs selected take ...

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The resistive component of the bulk capacitor ESR must be small enough that under a load release, ESR multiplied by the change in load current must meet the following criteria: ∆V > ∆I • R OUT(LOAD) LOAD ESR ...

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LTC3816 applicaTions inForMaTion and operating frequency. Given a specified limit for ripple current, the inductor value can be obtained using the fol- lowing equation:  OUT OUT –  ∆ f •  ...

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Conveniently, the typical probe tip ground clip is spaced just right to span the leads of a typical output capacitor. In general best to take this measurement with the 20MHz bandwidth limit on the oscilloscope turned ...

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LTC3816 applicaTions inForMaTion For this example, a Vishay IHLP-5050CE-01 0.33µH induc- tor is chosen. According to the inductor data sheet, it has a maximum DC current rating of 36.5A and a saturation current of 62A. At room temperature, the typical ...

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Therefore R is calculated to be 13.99k and standard SER value R = 14k is used. Next, the resistor R SER is obtained from the AVP slope requirement: (   SER PAR = ...

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LTC3816 applicaTions inForMaTion For the synchronous MOSFETs, assume that the two bottom MOSFETs share the inductor current equally. The power dissipation for one MOSFET is – OUT SYNC LOAD MAX ( ) ...

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As can be seen from the above equation, the biggest portion of the output ripple comes from the ESR of the capacitor. This is why low ESR capacitors are so important in low voltage, high current applications. PC ...

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LTC3816 Typical applicaTions An IMVP-6 Converter Using Current Sense Resistor with –5.7mV/A AVP Slope 4.75k 3.32k 33pF INTV CC GND TCFB PREI MON I MON RPTC 1000pF SS(SEN) V CC(SEN) SERVO 22pF ...

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Typical applicaTions LTC3816 3816f  ...

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LTC3816 package DescripTion 4.75 REF 6.60 ±0.10 4.50 REF 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. ...

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... ALL DIMENSIONS ARE IN MILLIMETERS 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. UHF Package 38-Lead Plastic QFN (5mm × ...

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... Dual 180° Phase Controllers, 4V ≤ V ≤ 28V, IN 97% Duty Cycle 4V ≤ V ≤ 38V, Very Low Dropout with Tracking IN Triple Phase Version of LTC3850 in a 40-Lead 6mm × 6mm QFN Package LT 0710 • PRINTED IN USA  LINEAR TECHNOLOGY CORPORATION 2010 = 27A ≤ 25A, 3816f ...