LM3492QMHX National Semiconductor Corporation, LM3492QMHX Datasheet
LM3492QMHX
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LM3492QMHX Summary of contents
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... Other supervisory functions of the LM3492 include precise enable, VCC under-voltage lock- out, current regulator over-power protection, and thermal shutdown protection. The LM3492 is available in the thermally enhanced eTSSOP-20 package. © 2010 National Semiconductor Corporation LM3492/LM3492Q Features Boost Converter: ■ ...
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... TSSOP-20 LM3492MHX LM3492QMH LM3492QMHX *Automotive Grade (Q) product incorporates enhanced manufacturing and support processes for the automotive market, including defect detection methodologies. Reliability qualification is compliant with the requirements and temperature grades defined in the AEC-Q100 standard. Automotive grade products are identified with the letter Q. For more information go to http://www.national.com/automotive. ...
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Pin Descriptions Pin Name Description 1 EN Enable 2 VIN Input Supply Voltage Switch Node 5 VOUT Output Voltage Sense 6 RT Frequency Control 7 FB Output Voltage Feedback 8 GND Analog Ground 9 IOUT2 Current Regulator ...
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Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. VIN, RT, VOUT to GND SW to GND SW to GND (Transient) ILIM to GND FB to GND COMM, ...
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Symbol Parameter Boost Converter I CDHC pin source current CDHC-SRC I CDHC pin sink current CDHC-SINK I CDHC pin leakage current CDHC-LEAKAGE I Integrated MOSFET peak current limit CL-MAX threshold I Half integrated MOSFET peak current limit CL-HALF threshold R ...
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Typical Performance Characteristics Unless otherwise specified the following conditions apply 200 mA shown in this datasheet. LED Quiescent Current Regulation vs Temperature LED www.national.com = 25° 12V with configuration ...
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Efficiency 0.2A) IN LED 30116117 Power 0.2A) LED 30116119 Steady State Operation (I = 0.2A) LED 30116121 I Regulation vs V LED ( = 0.2A) ILED Enable Transient (I LED LED 50% Dimming ...
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LED Dimming (I = 0.2A, Dimming frequency = 200Hz) LED Simplified Functional Block Diagram www.national.com 300 ns LED Dimming Pulse Width (I = 0.2A, Dimming frequency = 3.33 kHz) LED 30116123 8 30116124 30116103 ...
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Overview The LM3492 integrates a boost converter and a two-channel current regulator to implement a high efficient and cost effec- tive LED driver for driving two individually dimmable LED strings with a maximum power of 15W and an output voltage ...
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Current Limit The current limit I of the integrated MOSFET of the LM3492 CL provides a cycle-by-cycle current limit for protection. It ...
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If the voltage on the IOUTn ( pin is over 24V when channel n is on, the regulated current of channel n will be reduced linearly if the voltage further increases (as shown in Figure 5). The ...
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CDHC pin reaches its maximum, and these conditions last for 508 consecutively dimming signals applied on the DIMn pin. This means that the current of the LED string n does not reach its regulated value. ...
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As a result 1.98A. A standard value of 47 µH is L1(PEAK) selected for L , and its saturation current is larger than 1.98A The selection of the boost diode tors. The ...
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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted 20-Lead Plastic eTSSOP Package NS Package Number MXA20A 14 ...
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Notes 15 www.national.com ...
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