LTC4449 Linear Technology, LTC4449 Datasheet
LTC4449
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LTC4449 Summary of contents
Page 1
... The LTC4449 features a separate supply for the input logic to match the signal swing of the controller IC. If the input signal is not being driven, the LTC4449 activates a shutdown mode that turns off both external MOSFETs. The input logic signal is internally level-shifted to the bootstrapped supply, which functions 42V above ground ...
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... LTC4449EDCB#PBF LTC4449EDCB#TRPBF LTC4449IDCB#PBF LTC4449IDCB#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *Temperature grades are identifi label on the shipping container. Consult LTC Marketing for information on lead based fi nish parts. For more information on lead free part marking, go to: For more information on tape and reel specifi ...
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... Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: The LTC4449I is guaranteed to meet specifi cations over the full –40°C to 125°C operating junction temperature range. The LTC4449E is guaranteed to meet specifi cations from 0°C to 85°C with specifi cations over the – ...
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... LTC4449 TYPICAL PERFORMANCE CHARACTERISTICS Input Thresholds vs V Supply Voltage LOGIC 4.0 V IH(TG) 3.5 V IL(TG) 3.0 2.5 2.0 V IL(BG) 1.5 V 1.0 IH(BG) 0.5 0 3.0 3.5 4.0 4.5 5.0 5.5 6.0 V SUPPLY (V) LOGIC 4449 G01 Input Threshold Hysteresis vs V Supply Voltage LOGIC 0.35 0.30 0.25 0.20 0.15 0.10 0.05 0 3.0 3.5 4.0 4.5 5.0 5.5 6.0 V SUPPLY (V) LOGIC 4449 G04 V Undervoltage Lockout LOGIC Thresholds vs Temperature 2.9 2.8 RISING THRESHOLD 2.7 FALLING THRESHOLD 2.6 2.5 –40 –10 ...
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... Temperature 25 NO LOAD LOGIC t pHL(TG GND 20 t pLH(TG pLH(BG pHL(BG –40 – TEMPERATURE (°C) LTC4449 www.DataSheet4U.com Rise and Fall Time vs V (Boost) Supply Voltage 3.3nF LOAD TS = GND 10 t r(TG) t r(BG f(BG 5.5 3.5 4.0 4.5 5.0 V (BOOST) SUPPLY VOLTAGE (V) ...
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... LTC4449 PIN FUNCTIONS TG (Pin 1): High Side Gate Driver Output (Top Gate). This pin swings between TS and BOOST. TS (Pin 2): High Side MOSFET Source Connection (Top Source). BG (Pin 3): Low Side Gate Driver Output (Bottom Gate). This pin swings between V and GND. CC GND (Pin 4, Exposed Pad Pin 9): Chip Ground. The exposed pad must be soldered to PCB ground for optimal electrical and thermal performance ...
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... LTC4449 limits the input threshold values for V supply voltages greater than 5V. LOGIC The relationship between the transition thresholds and the three input states of the LTC4449 is illustrated in Figure 1. When the voltage greater than the threshold pulled up to BOOST, turning the IH(TG) high side MOSFET on ...
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... MOSFETs to ground during a IN switch transition. Output Stage A simplifi ed version of the LTC4449’s output stage is shown in Figure 2. The pull-up device on both the BG and TG outputs is an NPN bipolar junction transistor (Q1 and Q2) in parallel with a low resistance P-channel MOSFET (P1 and P2) ...
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... BG while driving a 3nF load. Similarly, the 0.8Ω pull-down APPLICATIONS INFORMATION Power Dissipation To ensure proper operation and long-term reliability, the LTC4449 must not operate beyond its maximum temperature rating. Package junction temperature can be calculated by )(θ ...
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... Be sure to solder the Exposed Pad on the back side of CC the LTC4449 packages to the board. Correctly soldered to a double-sided copper board, the LTC4449 has a thermal resistance of approximately 64°C/W. Failure to make good thermal contact between the exposed back side and the copper board will result in thermal resistances far greater ...
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... However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights. RUN1 PWM2 PWM1 PGOOD2 PGOOD1 PHSMD AVG I CLKOUT VINSNS CLKIN TRACK/SS1 FREQ CC V TRACK/SS2 LTC4449 www.DataSheet4U.com 4449f 11 ...
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... LTC4449 PACKAGE DESCRIPTION 2.00 0.10 (2 SIDES) 3.00 0.10 (2 SIDES) PIN 1 BAR TOP MARK (SEE NOTE 6) 0.200 REF 0.75 0.05 0.00 – 0.05 NOTE: 1. DRAWING IS NOT A JEDEC PACKAGE OUTLINE 2. DRAWING NOT TO SCALE 3. ALL DIMENSIONS ARE IN MILLIMETERS RELATED PARTS PART NUMBER DESCRIPTION LTC4442/LTC4442-1 High Speed Synchronous N-Channel MOSFET Driver LTC4444/LTC4444-5 High Voltage/High Speed Synchronous N-Channel MOSFET ...