LTC3531 LINER [Linear Technology], LTC3531 Datasheet
LTC3531
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LTC3531 Summary of contents
Page 1
... Buck-Boost Synchronous DC/DC DESCRIPTIO The LTC ® 3531/LTC3531-3.3/LTC3531-3 are synchronous buck-boost DC/DC converters that operate from input voltages above, below or equal to the output voltage. The topology incorporated in the ICs provides a continuous transfer through all operating modes, making the product ideal for single cell Li-Ion and multicell alkaline or nickel applications ...
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... PGND SW2 IN 9 GND OUT SHDN 4 5 FB* DD PACKAGE 8-LEAD (3mm × 3mm) PLASTIC DFN T = 125°C, θ = 43°C/W JMAX JA *NC FOR LTC3531-3.3V, LTC3531-3.0V. DD PART MARKING LBVC LBWH LCBV MIN TYP MAX ● 1.65 1.8 ● 3.25 3.32 3.39 ● 2.95 3.02 3.09 ● 1.20 1.225 1. ...
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... Continuous operation above the specifi ed maximum operating junction temperature may result in device degradation or failure. Note 3: The LTC3531 is guaranteed to meet performance specifi cations from 0°C to 70°C. Specifi cations over the –40°C to 85°C operating temperature range are assured by design, characterization and correlation with statistical process controls ...
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... LTC3531/ LTC3531-3.3/LTC3531 TYPICAL PERFOR A CE CHARACTERISTICS Start-Up into Resistive Load L = 10μ 1.5 2 2.5 3 3 (V) IN 3531 G07 Switch On Resistances 1000 3.3V D (PMOS) OUT 900 800 700 A (PMOS) 600 500 B,C (NMOS) 400 –40 – ...
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... G13 , IN 5V/DIV 5V/DIV V OUT 50mV/DIV 200mA/DIV 3531 G15 5V/DIV 5V/DIV V OUT 50mV/DIV 200mA/DIV 3531 G17 LTC3531 25°C unless otherwise specifi ed. A Buck Mode 3.3V 100mA OUT SW1 SW2 (AC 10μH 5μs/DIV 3531 G14 C = 22μF ...
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... LTC3531/ LTC3531-3.3/LTC3531 TYPICAL PERFOR A CE CHARACTERISTICS Boost Mode Waveforms at 2.5V , 3.3V 100mA IN OUT SW1 5V/DIV SW2 5V/DIV V (AC) OUT 50mV/DIV I L 200mA/DIV L = 10μH 5μs/DIV C = 22μF OUT Shorted Output SW1 5V/DIV SW2 5V/DIV V (AC) OUT 50mV/DIV I L 200mA/DIV L = 10μH 1μ ...
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... OUT SW1 (Pin 6/Pin 1): Buck-Boost Switch Pin Where Internal to GND. OUT Switches A and B are Connected. Connect the inductor from SW1 to SW2. Exposed Pad (Pin 9, DFN): Solder to PCB ground for optimal thermal performance. LTC3531/ and GND. IN ⎛ ⎞ ⎝ ⎜ ...
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... LTC3531/ LTC3531-3.3/LTC3531-3 W BLOCK DIAGRA V IN PEAK CURRENT LIMIT 365mA V IN UVLO 1.65V SHDN SHUTDOWN 8 SW1 SW2 SW A GATE DRIVERS AND ANTICROSS CONDUCTION BEST BUCK, 4SW, MODE DETECT BOOST STATE MACHINE AND LOGIC V OUT COMPARATOR THERMAL SHUTDOWN PGND GND COMBINED ...
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... In order to determine the best operating mode for the converter, the LTC3531 contains a second comparator that monitors the relative voltage difference between V and V . Input and output voltages in the various modes OUT as well as typical inductor currents are shown in Figure 1 ...
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... The part will be enabled again when the die temperature has dropped by 10°C (nominal). To deliver the power that the LTC3531 is capable of imperative that a good thermal path be provided to dissipate the heat generated within the pack- age ...
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... V programming resistors are needed for the adjustable version. The high operating frequency and low peak currents of the LTC3531 allow the use of low value, low profi le inductors and tiny external ceramic capacitors. Inductor Selection For best effi ciency, choose an inductor with high frequency core material, such as ferrite, to reduce core loses ...
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... LTC3531/ LTC3531-3.3/LTC3531 APPLICATIO S I FOR ATIO SHUTDOWN C OUT GND V – – SHDN OUT 5 – V GND – – SW1 SW2 – 1 SOT PIN-OUT Recommended Layout (SOT Versions) V OUT GND 3531fb ...
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... TA02a 2 AA Alkaline to 3V with ThinSOT (3V Version) V OUT 3V OUT 80mA 10μF 3531 TA03a USB to 5V with 3 × 3 DFN (Adjustable Version) V OUT 5V OUT 200mA R2 1M 10μ GND 324k 3531 TA04a LTC3531/ 95 100 POWER LOSS AT 3. 0.1 0.1 ...
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... LTC3531/ LTC3531-3.3/LTC3531-3 PACKAGE DESCRIPTIO 0.62 0.95 MAX REF 3.85 MAX 2.62 REF RECOMMENDED SOLDER PAD LAYOUT PER IPC CALCULATOR 0.20 BSC DATUM ‘A’ 0.30 – 0.50 REF NOTE: 1. DIMENSIONS ARE IN MILLIMETERS 2. DRAWING NOT TO SCALE 3. DIMENSIONS ARE INCLUSIVE OF PLATING Package 6-Lead Plastic TSOT-23 (Reference LTC DWG # 05-08-1636) 1.22 REF 1.50 – ...
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... OUTLINE 0.50 BSC 2.38 ±0.05 (2 SIDES) 3.00 ±0.10 1.65 ± 0.10 (4 SIDES) (2 SIDES) 0.75 ±0.05 0.00 – 0.05 MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE ON TOP AND BOTTOM OF PACKAGE LTC3531 0.115 0.38 ± 0.10 TYP 5 8 (DD) DFN 1203 4 1 0.25 ± 0.05 0.50 BSC 2.38 ±0.10 (2 SIDES) BOTTOM VIEW—EXPOSED PAD ...
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... TIMER CLPROG C1 100k PROG 22μF WALL NTC 100k 0.1μF www.linear.com ● L1 10μH SW1 SW2 V OUT 3. OUT 160mA LTC3531-3.3 C2 SHDN 10μF GND 3531 TA05 COMMENTS V : 2.6V to 16V 34V, IN OUT(MAX 4.2mA/5.5mA, I < 1μA, ThinSOT Package 0.85V to 5V 5V, IN OUT(MAX 19μ ...