lr645 Supertex, Inc., lr645 Datasheet
lr645
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lr645 Summary of contents
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... Block Diagram TRIM General Description The Supertex LR645 is a high input voltage, low output current linear regulator. It has a 3-terminal fi xed output voltage version available in TO-92, TO-220 and SOT-89 packages, as well as an adjustable voltage version available lead SOIC package. The 3-terminal version functions like any other low voltage 3-terminal regulator except it allows the use of much higher input voltages ...
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... Ordering Information Package Option Device TO-92 TO-243AA LR645N3 LR645N8 LR645 LR645N3-G LR645N8-G LR645N5-G LR645LG-G -G indicates package is RoHS compliant (‘Green’) Thermal Characteristics Power Package Dissipation @ SOIC 0.31W TO-92 0.74W TO-220 1.8W TO-243AA 1.6W * Mounted on FR4 board; 25mm x 25mm x 1.57mm Signifi cant PD increase possible on ceramic substrate ...
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... LR645 turns OFF its internal high voltage input line and output voltage, allowing the auxiliary voltage to power the V rent drawn by the LR645 from the high voltage line after start-up will therefore only be leakage current of the internal MOSFET switch, which is typically 0.1µA. ...
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... LR645: High Current SMPS Start-Up Circuit The 8 lead version of the LR645 has connections for an ex- ternal depletion-mode MOSFET for higher output current and external resistors for adjustable output voltage. As shown in Figure 2, the output current is increased to 150mA by using the Supertex 400V depletion-mode MOSFET DN2540. The ...
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... Figure 4: High Current Regulation AC Line 24V to 277V Figure 5: Typical Output Voltage vs Resistor Ratio DN2540N5 GATE V OUT LR645LG GND 250KΩ 8 2.5 3.0 3.5 Resistor Ratio (R2/R1) 5 LR645 5.0V 5.0V REG + 0 to 150mA OUT – 4.0 ...
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... JEDEC Registration MS-012, Variation AA, Issue E, Sept. 2005. Drawings not to scale Note 1 h Seating Plane 1.25 0.31 4.80 5.80 3. 4.90 6.00 3.90 1.50 0.51 5.00 6.20 4.00 6 θ1 Gauge L2 Plane Seating L θ Plane L1 View B View B h View A 0.25 0.40 1.27 1.04 0. BSC REF BSC 0.50 1.27 LR645 θ θ ...
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... MIN .170 Dimension NOM - (inches) MAX .210 Drawings not to scale Front View .014 .014 .175 - - - .022 .022 .205 Side View .125 .800 .095 .045 - - - .165 .105 .105 .055 LR645 L .500 - - - ...
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... View .270 - .230 .500 - .100 - - - - - - BSC .350 .030 .270 .580 .250 LR645 Thermal Pad D2 Q ΦP .100 .139 - - .135 .161 ...
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... MAX 1.60 0.56 JEDEC Registration TO-243, Variation AA, Issue C, July 1986. Drawings not to scale. (The package drawings in this data sheet may not refl ect the most current specifi cations. For the latest package outline information go to http://www.supertex.com/packaging.html.) Doc.# DSFP-LR645 B050807 ...