tb62731fugel Marktech Optoelectronics, tb62731fugel Datasheet
tb62731fugel
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tb62731fugel Summary of contents
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TOSHIBA BiCD Digital Integrated Circuit Silicon Monolithic Step-up DC-DC Converter for White LED Driver The TB62731FUG is an LED driver that uses a high power efficiency step-up DC-DC converter. The converter turns on/off white LEDs in series. ...
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Block Diagram V CC OSC 350 kHz SHDN STB REF i (add) GND Pin Functions No Symbol Pin connecting LED cathode to resistor used to set current Feedback pin for voltage waveforms for controlling the LED constant current. ...
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Absolute Maximum Ratings Characteristics Supply voltage Input voltage Pin A (anode) current Pin A voltage Power dissipation Saturation thermal resistance Operating temperature range Storage temperature range Maximum junction temperature Note: The power dissipation is derated by 3.8 mW/°C from the ...
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Electrical Characteristics (unless otherwise specified, Characteristics Supply voltage Current consumption at operation Current consumption at standby SHDN pin current Internal MOS transistor on-resistance Internal MOS transistor switching frequency Pin A voltage Pin A current Pin A leakage current Set LED ...
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V CC OSC 350 kHz SHDN V C1 STB IN REF Figure 1 Application Circuit The basic TB62731FUG circuit uses a step-up DC-DC converter and burst control of the current pulse. Basic Operation The internal MOS transistor (NMOS) is turned ...
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Maximum duty width for inductor on: 83. Pulse output time = 350 kHz width f OSC Pin A voltage Pin A current (external inductance current) Pin K voltage (current charged on capacitor) Figure 3 Burst Control Waveforms Burst ...
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Standby Operation The SHDN pin is used to set normal or standby operation. When SHDN is set to Low, the operation is standby; when the pin is High, the LED is turned on. Current consumption in Standby Mode is 1 ...
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Substitute the following conditions in formula 2. = 3.0~4.3 (V) Supply voltage V IN Output-side capacitor µ ignored in the calculation. Where it is assumed that, VfLED = 16 (V), ...
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Selection of R_sens Resistance between pin K and GND R_sens ( Ω used for setting output current I can be set according to the resistance. The mean current I (mA set is roughly calculated as follows: ...
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Output Derating Function Toshiba recommend derating the LED current depending on the increase in ambient temperature. The TB62731FUG is designed to ensure safe and efficient driving of white LEDs used as backlight sources for color LCDs. The IC incorporates a ...
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The self-generated temperature T up (°C) = ((0.32 − (0.32 × 0.7)) − (0.5 × 0.1 + 0.3 × 0.02 + 1.8 × 0.02 × 0.02)) × 260 = 10.2 (° Thus, the derating start temperature T (°C) ...
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Current consumption at normal operation I (ON) CC 900 800 700 600 500 400 300 200 100 0 3 3 (V) CC Current consumption at shutdown I (SHDN) CC 0.5 0.4 0.3 0.2 0 ...
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Application Circuit Example 1 Though it is necessary to consider the DC resistance of L1, an inductance (typ µ suitable for turning on four LEDs µH S- 3.2 ...
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Application Circuit Example 2 (characteristic using flat coil for handy terminal as reference) Flat coils suitable for handy terminals have a large DC resistance; thus, the power efficiency drops slightly, to about 70 µH S- 3.2 ...
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L1 4.7 µH S- 3.2 V~4 µF SHDN C1 OFF 4.7 µF K GND GND L1: Toko A914BYW-4R7 S-Di: Toshiba 1SS404 20 V/1A LED: Nichia NSCW215T R_sens: ⎯ µH ...
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Package Dimensions Weight: 0.016 g (typ.) 16 TB62731FUG 2004-09-14 ...
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About solderability, following conditions were confirmed • Solderability (1) Use of Sn-63Pb solder Bath · solder bath temperature = 230°C · dipping time = 5 seconds · the number of times = once · use of R-type flux (2) Use ...