LT1765-3.3 LINER [Linear Technology], LT1765-3.3 Datasheet
LT1765-3.3
Related parts for LT1765-3.3
LT1765-3.3 Summary of contents
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... High frequency operation allows the reduc- tion of input and output filtering components and permits the use of chip inductors. CMDSH-3 0.18 F 1.5 H OUTPUT 3. 2. 4.7 F 2.2nF UPS120 CERAMIC 1765 TA01 LT1765-3.3/LT1765-5 U Efficiency vs Load Current 10V OUT 1.0 1.5 2.0 0.5 SWITCH CURRENT (A) 1765 • ...
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... COPPER PLANE CONDITIONS 3.3V < V < 25V (Note 0V 25V SHDN < V < 25V, 0.4V < V < 0.9V LT1765 (Adj (Note 3) LT1765-1.8 LT1765-2.5 LT1765-3.3 LT1765-5 ORDER PART NUMBER TOP VIEW 16 GND LT1765EFE 15 NC LT1765EFE-1.8 14 SYNC LT1765EFE-2 LT1765EFE-3 LT1765EFE-5 11 SHDN ...
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... Note 3: Minimum input voltage is defined as the voltage where the internal regulator enters lockout. Actual minimum input voltage to maintain a regulated output will depend on output voltage and load current. See Applications Information. Note 4: Current flows into the BOOST pin only during the on period of the switch cycle. LT1765-3.3/LT1765 MIN TYP MAX UNITS – ...
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... LT1765/LT1765-1.8/LT1765-2.5/ LT1765-3.3/LT1765 TYPICAL PERFOR A CE CHARACTERISTICS FB vs Temperature (Adj) 1.220 1.215 1.210 1.205 1.200 1.195 1.190 1.185 1.180 0 50 –50 – 100 TEMPERATURE ( C) 1765 G01 SHDN Threshold vs Temperature 1.40 1.38 1.36 1.34 1.32 1.30 –50 – TEMPERATURE ( C) 4 Switch On Voltage Drop 350 ...
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... G10 Maximum Load Current 2.5V OUT 3 4 2 1.5 H 2.4 2 INPUT VOLTAGE (V) 1765 G12 LT1765-3.3/LT1765-5 Input Supply Current 1200 1000 UNDERVOLTAGE 800 LOCKOUT 600 400 200 0 1 INPUT VOLTAGE (V) Maximum Load Current OUT 3.0 2 4.7 H 2.6 2 ...
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... LT1765/LT1765-1.8/LT1765-2.5/ LT1765-3.3/LT1765 CTIO S FB: The feedback pin is used to set output voltage using an external voltage divider (adjustable version) that gen- erates 1.2V at the pin when connected to the desired output voltage. The fixed voltage 1.8V, 2.5V, 3.3V and 5V versions have the divider network included internally and the FB pin is connected directly to the output ...
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... CURRENT SENSE AMPLIFIER CC VOLTAGE GAIN = 40 0.4V 1.25MHz CURRENT COMPARATOR + – Figure 1. Block Diagram LT1765-3.3/LT1765-5 BOOST S R DRIVER S FLIP-FLOP CIRCUITRY R PARASITIC DIODES DO NOT FORWARD BIAS – + ERROR AMPLIFIER 1. 850 Mho m Q1 ...
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... LT1765/LT1765-1.8/LT1765-2.5/ LT1765-3.3/LT1765 APPLICATIO S I FOR ATIO FB RESISTOR NETWORK If an output voltage of 1.8V, 2.5V, 3. required, the respective fixed option part, -1.8, -2.5, -3.3 or -5, should be used. The FB pin is tied directly to the output; the necessary resistive divider is already included on the part. For other voltage outputs, the adjustable part should be used and an external resistor divider added ...
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... Care should be taken, however. At high input voltages and low DCR, excessive switch current could flow during shorted output condition. Suitable inductors are available from Coilcraft, Coiltronics, Dale, Sumida, Toko, Murata, Panasonic and other manufacturers. LT1765-3.3/LT1765 – V ...
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... LT1765/LT1765-1.8/LT1765-2.5/ LT1765-3.3/LT1765 APPLICATIO S I FOR ATIO Table 3 VALUE I RMS PART NUMBER ( H) (Amps) Coiltcraft DO1608C-222 2.2 2.4 Sumida CDRH3D16-1R5 1.5 1.6 CDRH4D18-1R0 1.0 1.7 CDC5D23-2R2 2.2 2.2 CR43-1R4 1.4 2.5 CDRH5D28-2R6 2.6 2.6 Toko (D62F)847FY-2R4M 2.4 2.5 (D73LF)817FY-2R2M 2.2 2.7 CATCH DIODE The diode D1 conducts current only during switch off time. Peak reverse voltage is equal to regulator input voltage. ...
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... LT1765 switch. When operating at higher currents and input voltages, with poor layout, this spike can generate voltages across the LT1765 that may exceed its absolute V IN LT1765-3.3/LT1765-5 LT1765 HIGH FREQUENCY ...
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... LT1765/LT1765-1.8/LT1765-2.5/ LT1765-3.3/LT1765 APPLICATIO S I FOR ATIO INPUT 15V C2 C3 0.18 F 4.7 F CERAMIC BOOST LT1765-33 OFF ON SHDN FB SYNC GND 2.2nF Figure 6. Typical Application and Layout (Topside Only Shown) maximum rating. A ground plane should always be used under the switcher circuitry to prevent interplane coupling and overall noise ...
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... The basic regulator loop is shown in Figure 7, with both tantalum and ceramic capacitor equivalent cir- cuits. The LT1765 can be considered as two g error amplifier and the power stage. LT1765 CURRENT MODE POWER STAGE C/ GND ) LT1765-3.3/LT1765-5 compensation OUTPUT ERROR = 5mho AMPLIFIER R1 FB TANTALUM – ...
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... LT1765/LT1765-1.8/LT1765-2.5/ LT1765-3.3/LT1765 APPLICATIO S I FOR ATIO Figure 8 shows the overall loop response with a 330pF V capacitor and a typical 100 F tantalum output capacitor. The response is set by the following terms: Error amplifier: DC gain set by g and R = 850 • 500k = 425 Pole set by C and • ...
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... L1B and C4. At switch off, the energy stored in both L1B and C4 supply the –5V rail. This reduces the current in L1A and changes L1B current waveform from square to triangular. For details on this circuit, including maximum output currents, see Design Note 100. LT1765-3.3/LT1765-5 CMDSH 3.3V, 2A ALTERNATE SUPPLY 4 ...
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... LT1765/LT1765-1.8/LT1765-2.5/ LT1765-3.3/LT1765 APPLICATIO S I FOR ATIO INPUT 12V GND * SINGLE CORE WITH TWO WINDINGS COILTRONICS CTX5-1A † IF LOAD CAN GO TO ZERO, AN OPTIONAL PRELOAD MAY BE USED TO IMPROVE LOAD REGULATION D1, D3: B220A CMDSH-3 C2 0.18 F BOOST ...
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... GND V C UPS120 4700pF 16V X5R C F CERAMIC R 100pF C 6.8k L1: CDRH5D28-2R5 BOLD LINES INDICATE HIGH CURRENT PATHS Figure 13. Negative Boost Converter LT1765-3.3/LT1765 6.3V X5R CERAMIC OUTPUT – 1765 F12 D2 CMDSH-3 INPUT – 2.2 F 6.3V X5R R2 ...
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... LT1765/LT1765-1.8/LT1765-2.5/ LT1765-3.3/LT1765-5 PACKAGE DESCRIPTIO 6.60 0.10 4.50 0.10 0.65 BSC RECOMMENDED SOLDER PAD 4.30 – 4.48* (.169 – .176) 0.50 – 0.70 0.105 – 0.180 (.020 – .028) (.0041 – .0071) NOTE: 1. CONTROLLING DIMENSION: MILLIMETERS MILLIMETERS 2. DIMENSIONS ARE IN (INCHES) 3. DRAWING NOT TO SCALE * DIMENSIONS DO NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.150mm (.006" ...
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... TYP 0.014 – 0.019 (0.355 – 0.483) TYP LT1765-3.3/LT1765 0.150 – 0.157** (3.810 – 3.988 0.004 – 0.010 (0.101 – 0.254) 0.050 (1 ...
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... LT1765/LT1765-1.8/LT1765-2.5/ LT1765-3.3/LT1765-5 RELATED PARTS PART NUMBER DESCRIPTION LT1370 High Efficiency DC/DC Converter LT1371 High Efficiency DC/DC Converter LT1372/LT1377 500kHz and 1MHz High Efficiency 1.5A Switching Regulators LT1374 High Efficiency Step-Down Switching Regulator LT1375/LT1376 1.5A Step-Down Switching Regulators LT1507 1.5A Step-Down Switching Regulator LT1576 1.5A Step-Down Switching Regulator LT1578 1 ...