LTC3832-1 Linear Technology, LTC3832-1 Datasheet
LTC3832-1
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LTC3832-1 Summary of contents
Page 1
... In shutdown mode, the LTC3832 supply current drops to <10 A. The LTC3832-1 is the SO-8 version without current limit, frequency adjustment and shutdown functions. , LTC and LT are registered trademarks of Linear Technology Corporation. ...
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... A CC CC1 CC2 CONDITIONS (Note 1.25V COMP V = 1.25V COMP 10A (Note 6) OUT V = 4.75V to 5.25V CC ORDER PART NUMBER TOP VIEW LTC3832-1ES8 / CC2 3 6 COMP PART MARKING S8 PACKAGE 8-LEAD PLASTIC SO 38321 = 125 C, ...
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... Note 8: The current limiting amplifier can sink but cannot source current. Under normal (not current limited) operation, the output current will be zero. Note 9: The LTC3832E/LTC3832-1E are guaranteed to meet performance specifications from Specifications over the – operating temperature range are assured by design, characterization and correlation with statistical process controls ...
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... LTC3832/LTC3832 TYPICAL PERFOR A CE CHARACTERISTICS Load Regulation 2. REFER TO FIGURE 12 2.53 2.52 2.51 2.50 2.49 2.48 2.47 2.46 –10 –5 5 – OUTPUT CURRENT (A) 3832 G01 Output Voltage Temperature Drift 2.55 REFER TO FIGURE 12 2.54 OUTPUT = NO LOAD 2.53 2.52 2.51 2.50 2.49 2.48 2.47 2.46 2.45 50 125 –50 – 100 TEMPERATURE ( C) 3832 G04 Oscillator Frequency vs Temperature 360 FREQSET FLOATING ...
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... G14 V Operating Supply Current CC vs Temperature 1.6 FREQSET FLOATING 1.5 1.4 1.3 1.2 1.1 1.0 0.9 0.8 0.7 0.6 0.5 0.4 –50 – 100 125 TEMPERATURE ( C) 3832 G17 LTC3832/LTC3832-1 Output Overcurrent Protection 3 REFER TO FIGURE 12 2.5 2.0 1.5 1.0 0 OUTPUT CURRENT (A) 3832 G12 Soft-Start Sink Current vs (V – V ...
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... SENSE and connect the external resistor divider to FB. The internal . It remains low if G2 resistor divider is not included in the LTC3832-1. SHDN (Pin 8/NA): Shutdown. A TTL compatible low level at SHDN for longer than 100 s puts the LTC3832 into + V ...
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... Connect this pin to a clean power supply, separate from the main V supply at the drain of Q1. This pin requires a 4 bypass capacitor. The LTC3832-1has V together at Pin 7 and requires bypass capacitor to sets MAX GND. ...
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... Figure APPLICATIO S I FOR ATIO OVERVIEW The LTC3832/LTC3832-1 are voltage mode feedback, synchronous switching regulator controllers (see Block Diagram) designed for use in high power, low voltage step-down (buck) converters. They include an onboard PWM generator, a precision reference trimmed to 0.8%, two high power MOSFET gate drivers and all necessary ...
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... QSS in the Block Diagram) above the voltage at the SS pin. This prevents the error amplifier from forcing the loop to maximum duty cycle. The LTC3832/LTC3832-1 operate at low duty cycle as the SS pin rises above 0. rise, QSS turns off and the error amplifier takes over to regulate the output ...
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... LTC3832/LTC3832 APPLICATIO S I FOR ATIO remains at a reduced voltage until the overload is re- moved. Serious overloads generate a large overdrive at CC, allowing it to pull SS down quickly and preventing damage to the output components. By using the measure the output current, the current limiting circuit eliminates an expensive discrete sense resistor that would otherwise be required ...
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... SHDN pin resets the internal oscillator and pulls the ramp signal low, this forces the LTC3832 internal oscil- lator to lock to the external clock frequency. The LTC3832-1 does not have this external synchronization function. The LTC3832 internal oscillator can be externally synchro- nized from 100kHz to 500kHz ...
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... G2 pin goes high and the switch node is pulled low by Q2 The G2 on-time becomes narrow when LTC3832/ V OUT LTC3832-1 operates at a maximum duty cycle (95% + typical), which can occur if the input supply rises more Q2 C OUT slowly than the soft-start capacitor or if the input voltage 3832 F7 droops during load transients ...
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... MOSFET. Assuming roughly 90% efficiency and at this current level, this gives a P CC1 specified (2.5V)(10A/0.9)(0.03) = 0.83W per FET and a required voltage and IN and CC1 LTC3832/LTC3832-1 may be quite high, raising DS(ON) V OUT – V OUT IN OUT ) 1 – V ...
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... LTC3832/LTC3832 APPLICATIO S I FOR ATIO Note that the required R for Q2 is roughly three DS(ON) times that this example. Note also that while the required R values suggest large MOSFETs, the DS(ON) power dissipation numbers are only 0.83W per device or less; large TO-220 packages and heat sinks are not neces- sarily required in high efficiency applications ...
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... Low cost, generic tantalums are known to have very short lives followed by explosive deaths in switching power supply applications. Other capacitors that can be used include the Sanyo POSCAP and MV-WX series. A common way to lower ESR and raise ripple current capability is to parallel several capacitors. A typical LTC3832/LTC3832-1 sn3832 3832fs 15 ...
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... LTC3832/LTC3832 APPLICATIO S I FOR ATIO LTC3832 application might exhibit 5A input ripple cur- rent. Sanyo OS-CON capacitors, part number 10SA220M (220 F/10V), feature 2.3A allowable ripple current three in parallel at the input (to withstand the input ripple current) meet the above requirements. Similarly, Sanyo POSCAP 4TPB470M (470 F/4V) capacitors have a maximum rated ESR of 0.04 ...
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... Traces carrying high current should be as wide as pos- 120 1500 sible. For example, a PCB fabricated with 2oz copper 100 1500 requires a minimum trace width of 0.15" to carry 10A. 100 1500 LTC3832/LTC3832 OUT C C 1410 13 0.0047 ...
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... LTC3832/LTC3832 APPLICATIO S I FOR ATIO 1. In general, layout should begin with the location of the power devices. Be sure to orient the power circuitry so that a clean power flow path is achieved. Conductor widths should be maximized and lengths minimized. After you are satisfied with the power path, the control circuitry should be laid out ...
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... 3. 2.5V 10 OUT REFER TO FIGURE LOAD CURRENT (A) 3832 F12b LTC3832/LTC3832 3. 330 F 2 1N5817 Q1A, Q1B 2 IN PARALLEL L O 0 OUT 2. 14A OUT Q2 D1 470 F 3 3832 F12a ...
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... LTC3832/LTC3832-1 U TYPICAL APPLICATIO 3. 330 2 SHUTDOWN 68pF 6. 0. Typical 3.3V to 5V, 5A Synchronous Boost Converter MBR0520 MBR0520 0 CC1 CC2 V 0 MAX 100 LTC3832 I FB FREQSET G1 SHDN PGND COMP GND + SENSE G2 FB – SENSE ...
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... SS I MAX 1k LTC3832 I FB FREQSET G2 13V SHDN COMP FB + SENSE PGND GND – SENSE SANYO POSCAP 6TPB330M IN OUT L : SUMIDA CDEP105-1R3-MC Q1, Q2: SILICONIX Si7440DP LTC3832/LTC3832 330 1 OUT 10 F 93.1k 330 F 1% 12. OUT –5V 3832 TA04 5A sn3832 3832fs 21 ...
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... LTC3832/LTC3832-1 PACKAGE DESCRIPTIO .254 MIN .0165 .0015 RECOMMENDED SOLDER PAD LAYOUT .007 – .0098 (0.178 – 0.249) .016 – .050 (0.406 – 1.270) NOTE: 1. CONTROLLING DIMENSION: INCHES INCHES 2. DIMENSIONS ARE IN (MILLIMETERS) 3. DRAWING NOT TO SCALE *DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.006" ...
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... TYP .016 – .050 .014 – .019 (0.406 – 1.270) (0.355 – 0.483) TYP INCHES (MILLIMETERS) LTC3832/LTC3832-1 .189 – .197 (4.801 – 5.004) NOTE .150 – .157 (3.810 – 3.988) NOTE 3 ...
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... LTC3832/LTC3832-1 U TYPICAL APPLICATIO + 100 0.1 F 4 SHUTDOWN 180pF 18k C C 0.01 F RELATED PARTS PART NUMBER DESCRIPTION LTC1530 High Power Synchronous Switching Regulator Controller LTC1628 Dual High Efficiency 2-Phase Synchronous Step-Down Controller LTC1702 Dual High Efficiency 2-Phase Synchronous Step-Down Controller LTC1705 ...