LTC3615EFE-1#TRPBF Linear Technology, LTC3615EFE-1#TRPBF Datasheet
LTC3615EFE-1#TRPBF
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LTC3615EFE-1#TRPBF Summary of contents
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... QFN and thermally enhanced 24-pin eTSSOP packages. L, LT, LTC, LTM, Linear Technology, Burst Mode and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents, including 5481178, 5994885, 6304066, 6498466, 6580258, 6611131. 0.47μ ...
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... LTC3615EFE#TRPBF LTC3615IFE#PBF LTC3615IFE#TRPBF LTC3615EUF#PBF LTC3615EUF#TRPBF LTC3615IUF#PBF LTC3615IUF#TRPBF LTC3615EFE-1#PBF LTC3615EFE-1#TRPBF LTC3615IFE-1#PBF LTC3615IFE-1#TRPBF LTC3615EUF-1#PBF LTC3615EUF-1#TRPBF LTC3615IUF-1#PBF LTC3615IUF-1#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. ...
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ELECTRICAL CHARACTERISTICS junction temperature range, otherwise specifi cations are at T otherwise specifi ed (Note 2). SYMBOL PARAMETER V Operating Voltage Range IN V Undervoltage Lockout Threshold UVLO V Feedback Voltage Internal Reference FB Feedback Voltage External Reference (Note 7) ...
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LTC3615/LTC3615-1 ELECTRICAL CHARACTERISTICS junction temperature range, otherwise specifi cations are at T otherwise specifi ed (Note 2). SYMBOL PARAMETER Output Phase Shift Between SW1 ϕ SW1–SW2 and SW2 (LTC3615) Output Phase Shift Between SW1 and SW2 (LTC3615-1) V Voltage at ...
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TYPICAL PERFORMANCE CHARACTERISTICS Effi ciency vs Load Current (V = 0V) MODE 100 V = 1.8V OUT 2. 3. 0.001 ...
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LTC3615/LTC3615-1 TYPICAL PERFORMANCE CHARACTERISTICS Forced Continuous Mode Operation (FCM) V OUT 20mV/DIV I L 200mA/DIV 3615 G09 V = 1.8V 1μs/DIV OUT I = 100mA OUT V = 1.5V MODE Load Step Transient in FCM External Compensation V OUT 200mV/DIV ...
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TYPICAL PERFORMANCE CHARACTERISTICS Reference Voltage vs Temperature 0.606 0.604 0.602 0.600 0.598 0.596 0.594 –50 –30 – TEMPERATURE (°C) Switch On-Resistance vs Temperature 100 90 MAIN SWITCH SYNCHRONOUS SWITCH ...
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LTC3615/LTC3615-1 TYPICAL PERFORMANCE CHARACTERISTICS Switch Leakage vs Temperature 2 5.5V IN 1.8 1.6 1.4 1.2 1.0 MAIN SWITCH 0.8 0.6 0.4 SYNCHRONOUS SWITCH 0.2 0 –40 – 110 125 –25 TEMPERATURE ...
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PIN FUNCTIONS (FE/UF) PHASE (Pin 1/Pin 4): Phase Shift Selection. If pin is tied to SGND, the phase between SW1 and SW2 will be 0° (LTC3615) or 140° (LTC3615-1). With the PHASE pin tied to half of the SV voltage, ...
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LTC3615/LTC3615-1 PIN FUNCTIONS (FE/UF) TRACK/SS1 (Pin 21/Pin 24): Internal, External Soft- Start, External Reference Input for Channel 1. The type of start-up behavior for channel 1 is programmable with the TRACK/SS1 pin: 1. Internal soft-start with a fi xed timing ...
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FUNCTIONAL BLOCK DIAGRAM PGOOD1 DELAY FB1 + – V REF IDEAL DIODE + – MODE TRACK/SS1 SOFT-START RUN1 RUN2 R /SYNC T PHASE SV IN UNDERVOLTAGE SGND LOCKOUT PGOOD2 FB2 TRACK/SS2 PGOOD WINDOW- COMPARATOR ERROR AMPLIFIER BURST COMPARATOR MODE + ...
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LTC3615/LTC3615-1 OPERATION Main Control Loop The LTC3615 is a dual monolithic step-down DC/DC converter featuring current-mode, constant-frequency operation. Both channels are identical and share common clock and reference circuits to improve channel-to-chan- nel matching. During normal operation, the internal top ...
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OPERATION Burst Mode Operation—External Clamp Connecting the MODE pin to a voltage in the range of 0.5V to 0.8V enables Burst Mode operation with external clamp. During this mode of operation, the minimum voltage on the ITH pin is externally ...
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LTC3615/LTC3615-1 OPERATION Low Supply Operation The LTC3615 is designed to operate down to an input supply voltage of 2.25V. An important consideration at low input supply voltages is that the R DS(ON) N-channel power switches increases by 50% compared to ...
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APPLICATIONS INFORMATION Operating Frequency Selection of the operating frequency is a trade-off between effi ciency and component size. High frequency operation allows the use of smaller inductor and capacitor values. Operation at lower frequencies improves effi ciency by reducing internal ...
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LTC3615/LTC3615-1 APPLICATIONS INFORMATION LTC3615 LTC3615 0.4V 2.25MHz R /SYNC R /SYNC T T SGND R OSC of periods to settle until the frequency at SW matches the frequency and phase ...
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APPLICATIONS INFORMATION the burst clamp. Lower inductor values result in higher ripple current which causes this to occur at lower DC load currents. This causes a dip in effi ciency in the upper range of low current operation. In Burst ...
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LTC3615/LTC3615-1 APPLICATIONS INFORMATION Output Capacitor C Selection OUT The selection typically driven by the required OUT ESR to minimize voltage ripple and load step transients (low-ESR ceramic capacitors are discussed in the next section). Typically, once the ...
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APPLICATIONS INFORMATION Output Voltage Programming The output voltages are set by external resistive dividers. For example, V can be set according to the following OUT2 equation: ⎛ ⎞ • ⎝ ...
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LTC3615/LTC3615-1 APPLICATIONS INFORMATION Applications section uses faster compensation to improve load step response. A second, more severe transient is caused by switching in loads with large (>1μF) supply bypass capacitors. The discharged bypass capacitors are effectively put in parallel with ...
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APPLICATIONS INFORMATION The LTC3615 allows the user to control the slew rate of the switching node SW by using the SRLIM pin. Tying this pin to ground selects the fastest slew rate. The slowest slew rate is selected when the ...
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LTC3615/LTC3615-1 APPLICATIONS INFORMATION Output Voltage Tracking Input If SRLIM is low, once V reaches or exceeds 0.6V TRACK/SS the run state is entered, and the MODE selection, power good and current foldback circuits are enabled. In the run state, the ...
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APPLICATIONS INFORMATION External Reference Input (DDR Mode) If SRLIM is tied the TRACK/SS pin can be used external reference input between 0.3V and 0.5V, if desired (see Figure 13). 0.6V V PIN FB VOLTAGE ...
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LTC3615/LTC3615-1 APPLICATIONS INFORMATION DDR Application The LTC3615 can be used in DDR memory power supply applications by tying the SRLIM pin to SV mode, the maximum slew rate is selected. The output can both source and sink current. Current sinking ...
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APPLICATIONS INFORMATION where the LTC3615 is running at high ambient temperature with low supply voltage and high duty cycles, such as in dropout, the heat dissipated may exceed the maximum junction temperature of the part. If the junction temperature reaches ...
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LTC3615/LTC3615-1 APPLICATIONS INFORMATION Decoupling the PV with two 47μF capacitors is adequate IN for most applications. Finally possible to defi ne the soft-start up time choosing the proper value for the capacitor and the resistor connected to TRACK/SS ...
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TYPICAL APPLICATIONS External Compensation, Forced Continuous Operation, In-Phase Switching, Slew Rate Limit, Common PGOOD Output V IN 3.3V 47μF 47μF RUN R C1 43k C C1 220pF R6 226k PGOOD R C2 43k C C2 220pF V Waveform OUT1 V ...
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LTC3615/LTC3615-1 TYPICAL APPLICATIONS Master and Slave for Coincident Tracking Outputs Using a 2MHz External Clock 47μF 47μF 10nF R5 100k C SYNC PGOOD1 15pF 2MHz CLOCK 10pF 200k 15k ...
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PACKAGE DESCRIPTION 3.25 (.128) 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 ...
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LTC3615/LTC3615-1 PACKAGE DESCRIPTION 4.50 ± 0.05 2.45 ± 0.05 (4 SIDES) 3.10 ± 0.05 RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS 4.00 ± 0.10 (4 SIDES) PIN 1 TOP MARK (NOTE 6) NOTE: 1. DRAWING PROPOSED TO BE MADE A JEDEC ...
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... LTC3615-1 added. Refl ected throughout the data sheet 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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... V = 0.6V 75μA, I OUT(MIN 2.25V to 5.5V 0.6V 75μA, I OUT(MIN 2.25V to 5.5V 0.6V 75μA, I OUT(MIN 0710 REV A • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2010 3615 F16 10 3615 F17 < 13μA, < 1μA, < 1μA, < 1μA, < 1μA, < 1μA, 3615fa ...