lm3508tl National Semiconductor Corporation, lm3508tl Datasheet
lm3508tl
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lm3508tl Summary of contents
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... During shutdown, the output is disconnected from the input preventing a leakage current path through the LEDs to ground. The LM3508 is available in a tiny 9-bump chip-scale micro-SMD package. Typical Application Circuit © 2007 National Semiconductor Corporation Features ■ Drives 4 Series White LEDs with up to 30mA ■ ...
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... Connection Diagram 9-Bump (Large) µ-SMD (1.514mm x 1.514mm x 0.6mm) NS Package Number TLA09 Ordering Information Part Number LM3508TL LM3508TLX Pin Descriptions/Functions Pin Name A1 PGND Power Ground Connection Inductor connection and drain connection for both NMOS and PMOS power devices. A3 OUT Output capacitor connection, PMOS source connection for synchronous rectifier, and OVP sensing node ...
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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 OUT ILED SET DIM EN Continuous Power ...
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Symbol Parameter I EN Bias Current EN (Note 8) I OUT Bias Current OUT R Output Pull-Down OUT_SHUTDOWN Resistance in Shutdown I Quiescent Current Q Device Not Switching I Switching Supply Q_SW Current t From EN Low to High START_UP ...
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LED Efficiency vs I LED = 0.66Ω TDK VLF3012AT-220MR33 Efficiency 20mA) IN LED Peak Current Limit Converter Output Voltage vs LED Current 30004258 Efficiency vs V 30004260 Switching ...
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Maximum Duty Cycle vs V Quiescent Current vs V (Device Not Switching, V SET Voltage vs DIM Frequency (50% Duty Cycle at DIM) www.national.com IN 30004215 30004216 30004219 6 Quiescent Current ...
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SET Voltage vs DIM Duty Cycle 30004262 PFET On-Resistance vs Temperature (V = 10.4V 10V) SW OUT Over Voltage Limit Falling) IN OUT NFET On-Resistance Over Voltage Limit 30004225 ...
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Over-Voltage Protection Function VIN = 3.6V 18.86V OUT Channel 1: V (1V/div) OUT Channel 4: I (500mA/div) IN Time Base: 400µs/div Output Short-Circuit Response V = 3.6V 30mA IN LED Channel 1: V (10V/div) OUT Channel ...
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Operation The LM3508 utilizes a synchronous step-up current mode PWM controller and a regulated current sink to provide a highly efficient and accurate LED current for white LED bias. The internal synchronous rectifier increases efficiency and eliminates the need for ...
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DIM Operation DIM is the input to the gate of an internal switch that accepts a logic level PWM waveform and modulates the internal 200mV reference through an internal RC filter. This forces the current source regulation point (V SET ...
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Once I is set, the LED current can be adjusted from LED_MAX I down applying a logic level PWM signal LED_MAX LED_MIN to DIM. This results in: where D is the duty cycle of the PWM pulse ...
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Table 2. Recommended Inductor Manufacturers MANUFACT L Part URER Number TDK 22µ VLF3010 2.6mm×2. H AT-220M 8mm×1m R33 TDK 22µ VLF3012 2.6mm×2. H AT-220M 8mm×1.2 R33 Toko 22u D3313FB 3.3mm×3. H (1036FB- 3mm×1.3 220M) LAYOUT CONSIDERATIONS Proper layout is essential ...
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Physical Dimensions inches (millimeters) unless otherwise noted For Ordering, Refer to Ordering Information Table X1 = 1.514mm (±0.03mm 1.514mm (±0.03mm 0.6mm (±0.075mm) 9-Bump Micro SMD Package (TL09AAA) NS Package Number TLA09AAA 13 www.national.com ...
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... National Semiconductor and the National Semiconductor logo are registered trademarks of National Semiconductor Corporation. All other brand or product names may be trademarks or registered trademarks of their respective holders. ...