ml4854 Fairchild Semiconductor, ml4854 Datasheet
ml4854
Related parts for ml4854
ml4854 Summary of contents
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... Detect In Low Battery Detect Out General Description The ML4854 is a low power boost regulator designed for low voltage conversion in two-cell battery pow- ered systems such as cell phones and PDAs. The converter starts up at 1.3V and has an operating input voltage range from 1.6V to 4.5V. After the start it operates at an input voltage as low as 0 ...
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... TSSOP (T08 GND IN SHDN LBI OUT LB0 TOP VIEW FUNCTION . OUT Min. -0.3 -0.3 -0.3 -65 ML4854 . When servicing IN Max. Units +0.3 OUT V V +0.3 OUT — Internally Limited — 500 mA 320 mW 124 °C/W 150 °C +165 °C 300 °C REV. 1.0.7 5/6/03 ...
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... ML4854 Recommended Operating Conditions Parameter Temperature Range V Operating Range IN V Operating Range OUT Electrical Characteristics Unless otherwise specified, V =1. +25°C A Parameter Start Up Voltage Operating Voltage Output Voltage Output Voltage Adjust Range Steady State Output Current (see diagram) ...
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... R1 JP2 750K SHDN 2 1 JP3 Reset 47µF R2 240K Ext Pull GND UP1B100 10uH U1 ML4854 1 8 Vin Gnd 2 7 Shut down LBI Vout 4 5 LBO FB C3 18pF R3 100K JP1 R6 287K Figure 1. Test Circuit ML4854 J1 C4 SCOPE JACK 1 ...
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... ML4854 Typical Operating Characteristics Maximum Steady State Load Current vs. Input Voltage 500 400 V = 3.3V OUT 300 OUT 200 100 1.5 2 2.5 Input Voltage, V Efficiency vs. Load Current Vout = 5V 100.0 Vin=3V 90.0 80.0 Vin=2.0V Vin=1.5V 70.0 60.0 50.0 40.0 30.0 20.0 10.0 0.0 0 Output Current, mA Starting Up and turning Off VOUT=5V Iload=10mA/50mA 5 TURN OFF: Iload=10mA ...
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... PRODUCT SPECIFICATION Typical Operating Characteristics Line Transient Response @100mA Load Exiting Shutdown V OUT V SHDN Heavy-Load Switching Waveforms OUT 6 (Continued) Inductor Current and Switching Node Voltage Inductor Current V L Load Transient Response V OUT ML4854 I LOAD REV. 1.0.7 5/6/03 ...
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... ML4854 Typical Operating Characteristics Output Voltage vs. Temperature 3.33 3.325 3.32 3.315 50mA 3.31 3.305 300 mA 3.3 3.295 3.29 -50 0 Temperature, C Start-up Voltage vs. Load Current 1.8 1.6 Vout=5V 1.4 1 100 150 Load Current, mA Operating Frequency, Vout=3.3V 500 450 400 350 300 250 200 150 100 1.5 2 Vin, V REV. 1.0.7 5/6/03 (Continued) Output Voltage vs ...
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... SHDN LIMIT Functional Description Boost regulator ML4854 is an adjustable boost regulator that combines vari- able ON and minimum OFF architecture with synchronous rectification. Unique control circuitry provides high-effi- ciency power conversion for both light and heavy loads by transitioning between discontinuous and continuous conduc- tion based on load conditions. There is no oscillator ...
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... ML4854 The synchronous rectifier significantly improves efficiency without the addition of an external component, so that conversion efficiency can be as high as 94% over a large load range, as shown in the “Typical Operating Characteristics.” Even at light loads, the efficiency stays high because the switching losses of the converter are minimized by reducing the switching frequency ...
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... If a tantalum capacitor is used, a 100nF ceramic capacitor in parallel, placed close to the IC, is recommended. Input Capacitor Selection Since the ML4854 does not require a large decoupling capacitor at the input to operate properly, a 47µF capacitor is sufficient for most applications requiring a good transient response of the regulator. Optimum effi ...
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... Place the external networks for LBI and FB close to ML4854, but as far away as possible from the power components to prevent voltage transient from coupling into sensitive nodes. Application Example: Using ML4854 as a constant current source to drive four LEDs: L ML4854 ...
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... PRODUCT SPECIFICATION Mechanical Dimensions Package: T08 8-Lead TSSOP 0.113 - 0.123 (2.87 - 3.12) 8 PIN 0.026 BSC (0.65 BSC) 0.008 - 0.012 0.033 - 0.037 (0.20 - 0.30) (0.84 - 0.94) SEATING PLANE 12 0.169 - 0.177 0.246 - 0.258 (4.29 - 4.50) (6.25 - 6.55) 0.043 MAX (1.10 MAX) 0°-8° 0.020 - 0.028 0.002 - 0.006 (0.51 - 0.71) (0.05 - 0.71) ML4854 0.004 - 0.008 (0.10 - 0.20) REV. 1.0.7 5/6/03 ...
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... A critical component in any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system affect its safety or effectiveness. ML4854 Package 8 Pin TSSOP (T08) 5/6/03 0.0m 004 Stock#DS30004854 © 2003 Fairchild Semiconductor Corporation ...