LTC1751-5 LINER [Linear Technology], LTC1751-5 Datasheet
LTC1751-5
Related parts for LTC1751-5
LTC1751-5 Summary of contents
Page 1
... They have thermal shutdown capability and can survive a continuous short circuit from V PGOOD pin on the LTC1751-3.3 and LTC1751-5 indicates when the output voltage has reached its final value and if the output has an undervoltage fault condition. The FB pin of the adjustable LTC1751 can be used to program the desired output voltage or current ...
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... OUT GND 4 MS8 PACKAGE 8-LEAD PLASTIC MSOP T = 150 C, JMAX *PGOOD ON LTC1751-3.3/LTC1751 LTC1751 Consult factory for parts specified with wider operating temperature ranges. The denotes specifications which apply over the full specified = FLY IN CONDITIONS ...
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... F FLY 3. 2. 3.25 3. 100 125 150 LOAD CURRENT (mA) 1751 G01 LTC1751/LTC1751-3.3/LTC1751-5 The denotes specifications which apply over the full specified = FLY IN CONDITIONS Relative to Regulated V (Note 6) OUT (Note 6) OUT I = – 500 A PGOOD V = 5.5V PGOOD V 3 ...
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... OUT 0.001 0.01 0.1 LOAD CURRENT (mA) Start-Up SHDN 2V/DIV PGOOD 5V/DIV V OUT 1V/DIV C = 10nF 2ms/DIV SS 1751 G06 (LTC1751-5) Output Voltage vs Output Current 5 FLY 5.1 5.0 V 4.9 4 OUTPUT CURRENT (mA) 4 Short-Circuit Output Current vs Input Voltage 250 200 V = 2.75V ...
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... G13 CTIO S PGOOD (Pin 1) (LTC1751-3.3/LTC1751-5): Output Volt- age Status Indicator. On start-up, this open-drain pin re- mains low until the output voltage, V (typ) of its final value. Once V is valid, PGOOD becomes OUT high-Z. If, due to a fault condition, V OUT its correct regulation level, PGOOD pulls low ...
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... LTC1751/LTC1751-3.3/LTC1751 PLIFIED BLOCK DIAGRA S PGOOD V OUT V IN GND FB V OUT V IN GND 6 W LTC1751-3.3/LTC1751-5 READY + – – – + – + UNDERV + 2 COMP1 – CHARGE PUMP 3 4 LTC1751 COMP1 – CHARGE PUMP REF CONTROL 7 SHDN + 6 C – ...
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... LTC1751/LTC1751-3.3/LTC1751 moderate to high output power, the switching losses and quiescent current of the LTC1751 are negligible and the expression is valid. For example, an LTC1751-5 with measured efficiency of 82% which is in close agreement with the theoretical 83.3% calculation. The LTC1751 prod- ...
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... ESR of the output capacitor proportional to the input voltage, the value of the flying capacitor and the ESR of the output capacitor. For example, typical combined output ripple for an LTC1751-5 with V 75mV P-P output capacitor and/or larger output current load will result in higher ripple due to higher output voltage slew rates ...
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... SS For example, with a 4.7nF capacitor the 10% to 90% rise time will be approximately 2.8ms. If the output charge storage capacitor then the average output current for an LTC1751-5 will be 4V/2.8ms • 14mA, giving 28mA at the V pin. IN The soft-start feature is optional. If there is no capacitor on SS, the output voltage of the LTC1751 will ramp up as quickly as possible ...
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... U U APPLICATIO S I FOR ATIO Programming the LTC1751 Output Voltage (FB Pin) While the LTC1751-3.3/LTC1751-5 versions have internal resistive dividers to program the output voltage, the programmable LTC1751 may be set to an arbitrary voltage via an external resistive divider. Since it employs a voltage doubling charge pump not possible to achieve output voltages greater than twice the available input voltage ...
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... IN OUT LTC1751 LOAD 7 SHDN OFF GND – 75k OUT + 10 F 3-CELL LTC1751-5 + NiCd + BATTERY PGOOD 8 SS SHDN GND 330pF 4 BAT54C 7 LTC1540 4 – 10k HYST – ...
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... LTC1751/LTC1751-3.3/LTC1751-5 U TYPICAL APPLICATIO Current Mode White or Blue LED Driver with PWM Brightness Control 3V TO 4.5V Li-Ion C1 BATTERY SHDN PACKAGE DESCRIPTIO 0.007 0 – 6 TYP (0.18) SEATING PLANE 0.021 0.006 (0.53 0.015) * DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. MOLD FLASH, PROTRUSIONS OR GATE BURRS SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE ** DIMENSION DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS. INTERLEAD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.006" ...