LTC1265-5 Linear Technology, LTC1265-5 Datasheet
LTC1265-5
Related parts for LTC1265-5
LTC1265-5 Summary of contents
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... COILTRONICS CTX33-4 ** IRC LRC2010-01-R100-J MBRS130LT3 † AVX TPSE227K010 †† AVX TPSE686K020 ††† LTC1265-FO1 1.2A, High Efficiency U 1265 is a monolithic step-down current mode TM operation at low LTC1265-5 Efficiency 100 12V ...
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... LTC1265C V = 9V, LTC1265I IN LTC1265-3. 800mA LOAD LTC1265- 800mA LOAD V = 6.5V to 10V 800mA IN LOAD LTC1265-3.3: 10mA < I < 800mA LOAD LTC1265-5: 10mA < I < 800mA LOAD I = 0mA LOAD Active Mode: 3.5V < V < 10V IN Sleep Mode: 3.5V < V < 10V IN Sleep Mode: 5V < V < 10V (LTC1265-5) IN Shutdown 3.5V < V < ...
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... Note 4: In applications where R A off time increases by approximately 40%. Efficiency vs Input Voltage (V = 5V) OUT 100 250mA LOAD 800mA LOAD LTC1265 0.1 SENSE C = 130pF T 82 COIL = CTX33 INPUT VOLTAGE (V) 1265 G02 Switch Resistance 0 ...
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... For the LTC1265 adjustable version, this FB pin serves as the feedback pin from an external resistive divider used to set the output voltage. On the LTC1265-3.3 and LTC1265-5 versions, this pin is not used SHDN (Pin 10): Pulling this pin HIGH keeps the internal switch off and puts the LTC1265 in micropower shut- down ...
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... When the load is heavy, the LTC1265 is in continuous operation. During the switch ON time, current comparator C monitors the voltage between Pins 7 and 8 connected across an external shunt in series with the inductor. When LTC1265/LTC1265-3.3/LTC1265-5 W (Pin 9 connection shown for LTC1265-3.3 and LTC1265-5; change create LTC1265) PWR ...
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... LTC1265/LTC1265-3.3/LTC1265-5 U OPERATION (Refer to Functional Diagram) capacitor discharges past V until its voltage drops TH1 below V . Comparator S then trips and a sleep signal is TH2 generated. The circuit now enters into sleep mode with the power MOSFET turned off. In sleep mode, the LTC1265 is in standby and the load current is supplied by the output capacitor ...
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... Thus V in regulation. Note that as V decreases, the frequency decreases. IN When the input-to-output voltage differential drops below LTC1265/LTC1265-3.3/LTC1265 2V, the LTC1265 reduces t current in C dropout. (See shelving effect shown in the Operating Frequency curve under Typical Performance Character- istics ...
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... LTC1265/LTC1265-3.3/LTC1265 APPLICATIONS INFORMATION P-channel switch duty cycle. At high input voltages, the diode conducts most of the time the diode conducts only a small fraction of the time. The most stressful condition for the diode is when the output is short circuited. Under this condition, the diode must safely handle I at close to 100% duty cycle ...
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... LTC1265 V FB SGND 11 Figure 4. LTC1265 Adjustable Configuration LTC1265/LTC1265-3.3/LTC1265 THERMAL CONSIDERATIONS In a majority of applications, the LTC1265 does not dissipate much heat due to its high efficiency. However, in applications where the switching regulator is running at high duty cycles or the part is in dropout with the switch turned on continuously (DC), the user will need to do some thermal analysis ...
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... LTC1265/LTC1265-3.3/LTC1265 APPLICATIONS INFORMATION Board Layout Checklist When laying out the printed circuit board, the following checklist should be used to ensure proper operation of the LTC1265. These items are also illustrated graphically in the layout diagram of Figure 5. Check the following in your layout: 1. Are the signal and power grounds segregated? The LTC1265 signal ground (Pin 11) must return to the (– ...
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... Figure 6a. 3.3V 2.4V 0V TIME (a) CONTINUOUS MODE OPERATION (a) POORLY DECOUPLED LTC1265 LTC1265/LTC1265-3.3/LTC1265 When the load currents are low (I Mode operation occurs. The voltage on C ground for periods of time as shown in Figure 6b. During this time the LTC1265 is in sleep mode with quiescent current reduced to 160 A ...
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... LTC1265/LTC1265-3.3/LTC1265 APPLICATIONS INFORMATION Design Example As a design example, assume 0.8A and f = 250kHz. With this information we can easily calculate all the important components. From (1 100mV/0.8 = 0.125 SENSE From (2) and assuming V = 0.4V 100pF T Using (3), the value of the inductor is ...
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... I NC THR 7 8 – + SENSE SENSE 1000pF Positive-to-Negative (–5V) Converter V IN 3. TP0610L V PWR LTC1265 PGND OUT 220pF SGND T 2200pF SHDN THR 7 8 – + SENSE SENSE 1000pF † L1 †† ...
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... LTC1265/LTC1265-3.3/LTC1265-5 U TYPICAL APPLICATIONS V (V) I (mA) IN OUT(MAX) 3.5V TO 7.5V 3.5 240 4.0 275 5.0 365 6.0 490 7.0 610 7.5 665 75pF L1A L1B 3 2 TOP VIEW 3300pF • L1A L1B SANYO OS-CON CAPACITOR * IRC LRC2010-01-R162-J ** L1A, L2A SELECTION † PART NO. MANUFACTURER CTX33-4 COILTRONICS LPT4545-330LA DALE V (V) ...
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... 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 represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. LTC1265/LTC1265-3.3/LTC1265-5 2.5mm Max Height 5V-to-3.3V (500mA) + ...
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... LTC1265/LTC1265-3.3/LTC1265-5 U TYPICAL APPLICATIONS 12. FAST CHARGE TRICKLE CHARGE: > 2V 270pF VN2222L 3300pF PACKAGE DESCRIPTION 0.010 – 0.020 45 0.053 – 0.069 (0.254 – 0.508) (1.346 – 1.752) 0.008 – 0.010 (0.203 – 0.254) 0 – 8 TYP 0.014 – 0.019 0.016 – ...