LTC3865IFE#PBF Linear Technology, LTC3865IFE#PBF Datasheet
LTC3865IFE#PBF
Specifications of LTC3865IFE#PBF
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LTC3865IFE#PBF Summary of contents
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... Packages APPLICATIONS n DC Power Distribution Systems L, LT, LTC, LTM, Burst Mode, OPTI-LOOP , μModule, Linear Technology and the Linear logo are registered trademarks and trademark of Linear Technology Corporation. All SENSE other trademarks are the property of their respective owners. U.S. Patents, including 5481178, 5705919, 5929620, 6100678, 6144194, 6177787, 6304066, 6580258 ...
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LTC3865/LTC3865-1 ABSOLUTE MAXIMUM RATINGS Input Supply Voltage (V ) ......................... –0.3V to 40V IN Topside Driver Voltages BOOST1, BOOST2 .................................. –0.3V to 46V Switch Voltage (SW1, SW2) ......................... –5V to 40V INTV , RUN1, RUN2, PGOOD(s), EXTV CC (BOOST1-SW1), (BOOST2-SW2) ...
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... LTC3865IUH-1#PBF LTC3865IUH-1#TRPBF LTC3865EFE#PBF LTC3865EFE#TRPBF LTC3865IFE#PBF LTC3865IFE#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi 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: For more information on tape and reel specifi ...
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LTC3865/LTC3865-1 ELECTRICAL CHARACTERISTICS junction temperature range, otherwise specifi cations are at T SYMBOL PARAMETER Main Control Loops V Input Voltage IN V Output Voltage Sensing (E-Grade) OSENSE1,2 Output Voltage Sensing (I-Grade) I Feedback Current OSENSE1,2 V Reference Voltage Line Regulation ...
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ELECTRICAL CHARACTERISTICS junction temperature range, otherwise specifi cations are at T SYMBOL PARAMETER Driver Pull-Down On-Resistance DOWN TG1 Transition Time: r TG1,2 t Rise Time f Fall Time BG1 Transition Time: r BG1,2 ...
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LTC3865/LTC3865-1 TYPICAL PERFORMANCE CHARACTERISTICS Effi ciency vs Load Current 100 BURST 60 DCM CCM 12V 1.5V OUT FIGURE 16 CIRCUIT 0 0.01 0 LOAD CURRENT ...
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TYPICAL PERFORMANCE CHARACTERISTICS Tracking Up and Down with External Ramp (Forced Continuous Mode) TK/SS1 TK/SS2 2V/DIV V = 1.5V OUT1 1Ω LOAD 500mV/DIV V = 1.2V OUT2 1Ω LOAD 500mV/DIV 20ms/DIV Current Sense Threshold vs I Voltage ...
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LTC3865/LTC3865-1 TYPICAL PERFORMANCE CHARACTERISTICS Shutdown (RUN) Threshold vs Temperature 1.5 1.4 1.3 ON 1.2 OFF 1.1 1.0 50 –50 – 100 TEMPERATURE (°C) 3865 G15 Undervoltage Lockout Threshold (INTV ) vs Temperature CC 5 RISING 4 FALLING ...
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PIN FUNCTIONS (QFN/TSSOP (Pins 1, 8/Pins 5, 13): When the OSENSE1 OSENSE2 internal programmable resistive divider is used, these pins must be connected to their corresponding outputs. When an external resistive divider is used, these pins are ...
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LTC3865/LTC3865-1 PIN FUNCTIONS (QFN/TSSOP) MODE/PLLIN (Pin 27/Pin 36): Force Continuous Mode, Burst Mode or Pulse-Skip Mode Selection Pin and External Synchronization Input to Phase Detector Pin. Connect this pin to SGND to force both channels in continuous mode of operation. ...
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FUNCTIONAL DIAGRAM FREQ/FREQ MODE/PLLIN VID1 7.5μA INPUT VID LOGIC AND RESISTIVE DIVIDERS MODE/SYNC DETECT PLL-SYNC AND LPF OSC – I CMP + – SLOPE COMPENSATION I LIM INTV CC UVLO 1 SLOPE RECOVERY 51k ACTIVE CLAMP ...
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LTC3865/LTC3865-1 OPERATION Main Control Loop The LTC3865/LTC3865-1 are constant-frequency, current mode step-down controllers with two channels operating 180 degrees out-of-phase. During normal operation, each top MOSFET is turned on when the clock for that channel sets the RS latch, and ...
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OPERATION pin voltage below 0.6V (e.g., SGND). To select pulse-skipping mode of operation, tie the MODE/PLLIN pin to INTV . To select Burst Mode operation, fl oat the CC MODE/PLLIN pin. When a controller is enabled for ...
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LTC3865/LTC3865-1 OPERATION bad mask is 100μs when there are any VID transitions. On the LTC3865-1 (UH32 package) or the LTC3865 (FE38 package), each channel has its own PGOOD pin. Therefore, the PGOOD pins now only respond to their own channels. ...
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APPLICATIONS INFORMATION Filter components mutual to the sense lines should be placed close to the LTC3865/LTC3865-1, and the sense lines should run close together to a Kelvin connection underneath the current sense element (shown in Figure 1). Sensing current elsewhere ...
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LTC3865/LTC3865-1 APPLICATIONS INFORMATION the sense traces on the PCB. A typical fi lter consists of two series 10Ω resistors connected to a parallel 1000pF capacitor, resulting in a time constant of 20ns. This same RC fi lter, with minor modifi ...
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APPLICATIONS INFORMATION always the same and varies with temperature; consult the manufacturers’ data sheets for detailed information. Using the inductor ripple current value from the Induc- tor Value Calculation section, the target sense resistor value is: V SENSE MAX ( ...
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LTC3865/LTC3865-1 APPLICATIONS INFORMATION Lower ripple current reduces core losses in the inductor, ESR losses in the output capacitors, and output voltage ripple. Thus, highest effi ciency operation is obtained at low frequency with a small ripple current. Achieving this, however, ...
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APPLICATIONS INFORMATION which are highest at high input voltages. For V the high current effi ciency generally improves with larger MOSFETs, while for V > 20V the transition losses rapidly IN increase to the point that the use of a ...
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LTC3865/LTC3865-1 APPLICATIONS INFORMATION TIME (5a) Coincident Tracking Figure 5. Two Different Modes of Output Voltage Tracking V OUT1 nR3 R1 TO TK/SS2 PIN nR4 R2 (6a) Coincident Tracking Setup Figure 6. Setup for Coincident and Ratiometric Tracking shown in Figure ...
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APPLICATIONS INFORMATION When the master channel’s output experiences dynamic excursion (under load transient, for example), the slave channel output will be affected as well. For better output regulation, use the coincident tracking mode instead of ratiometric. INTV Regulators and EXTV ...
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LTC3865/LTC3865-1 APPLICATIONS INFORMATION For applications where the main input power is below 5V, tie the V and INTV pins together and tie the combined IN CC pins to the 5V input with a 1Ω or 2.2Ω resistor as shown in ...
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APPLICATIONS INFORMATION maximum RMS current of one channel must be used. The maximum RMS capacitor current is given by ⎡ ⎣ MAX ≈ quired RMS OUT V IN This formula has a maximum ...
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LTC3865/LTC3865-1 APPLICATIONS INFORMATION Fault Conditions: Current Limit and Current Foldback The LTC3865/LTC3865-1 include current foldback to help limit load current when the output is shorted to ground. If the output falls below 50% of its nominal output level, then the ...
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APPLICATIONS INFORMATION If the external clock frequency is greater than the inter- nal oscillator’s frequency then current is sourced OSC continuously from the phase detector output, pulling up the fi lter network. When the external clock frequency is ...
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LTC3865/LTC3865-1 APPLICATIONS INFORMATION Supplying INTV power through EXTV CC output-derived source will scale the V quired for the driver and control circuits by a factor of (Duty Cycle)/(Effi ciency). For example 20V to 5V application, 10mA of INTV ...
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APPLICATIONS INFORMATION The I series R -C fi lter sets the dominant pole-zero loop compensation. The values can be modifi ed slightly (from 0 times their suggested values) to optimize transient response once the fi ...
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LTC3865/LTC3865-1 APPLICATIONS INFORMATION VID11 I TH1 V OSENSE1 SENSE1 SENSE1 FREQ I LIM f MODE/PLLIN IN RUN1 RUN2 SGND SENSE2 SENSE2 V OSENSE2 I TH2 TK/SS2 Figure 12. Recommended Printed Circuit Layout Diagram 28 TK/SS1 R PU2 V PULL-UP PGOOD ...
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APPLICATIONS INFORMATION BOLD LINES INDICATE HIGH SWITCHING CURRENT. KEEP LINES TO A MINIMUM LENGTH. SW1 L1 R SENSE1 D1 C OUT1 SW2 L2 R SENSE2 D2 C OUT2 Figure 13. Branch Current Waveforms LTC3865/LTC3865-1 ...
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LTC3865/LTC3865-1 APPLICATIONS INFORMATION 6. Keep the switching nodes (SW1, SW2), top gate nodes (TG1, TG2), and boost nodes (BOOST1, BOOST2) away from sensitive small-signal nodes, especially from the opposite channel’s voltage and current sensing feed- back pins. All of these ...
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APPLICATIONS INFORMATION Design Example As a design example for a 2-channel medium current regulator, assume V = 12V (nominal (maximum 3.3V 1.8V, I OUT1 OUT2 f = 500kHz (see Figure 14). The regulated output ...
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LTC3865/LTC3865-1 APPLICATIONS INFORMATION With I fl oating, the equivalent R LIM can be calculated by using the minimum value for the maximum current sense threshold (44mV). V SENSE MIN ( = R SENSE EQUIV ( ) Δ LOAD ...
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APPLICATIONS INFORMATION A short-circuit to ground will result in a folded back cur- rent of ⎛ – ⎝ ⎜ SC Ω μ 0 008 . 2 ...
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LTC3865/LTC3865-1 TYPICAL APPLICATIONS 10μF 35V 4.7μF RJK0305DPB 0.1μF L1 0.47μH RJK0330DPB 100Ω 2mΩ 0.1μF 100Ω 6800pF + C OUT1 1.21k 220μF 100pF SANYO 4TPE 220μF OUT1 OUT2 L1, L2: VISHAY IHLP4040DZERR47M11 Figure 17. High Current, ...
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PACKAGE DESCRIPTION 5.50 0.05 4.10 0.05 3.45 0.05 3.50 REF (4 SIDES) 3.45 0.05 RECOMMENDED SOLDER PAD LAYOUT APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED 5.00 0.10 (4 SIDES) PIN 1 TOP MARK (NOTE 6) NOTE: 1. DRAWING ...
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... DRAWING NOT TO SCALE 36 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. FE Package 38-Lead Plastic TSSOP (4.4mm) ...
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REVISION HISTORY REV DATE DESCRIPTION A 04/10 Updated Temperature Range in Order Information Section Updated Electrical Characteristics Table and Note 2 Updated Graph G08 Added Two Graphs to Typical Application Updated Related Parts B 08/10 Added (Note 9) notation to ...
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... QFN-12, MSOP-12 OUT = 43ns, 4V ≤ V ON(MIN SSOP-16, MSOP-16E, 3mm × 3mm QFN-16 ≤ 0.9V OUT IN = 30ns, 4V ≤ V ≤ 38V, ON(MIN MSOP-16E, 3mm × 3mm QFN-16 ≤ 0.8V OUT IN LT 0810 REV B • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2010 ≤ 38V, 3865fb ...