OM5448TR Hendon Semiconductors, OM5448TR Datasheet
OM5448TR
Specifications of OM5448TR
Related parts for OM5448TR
OM5448TR Summary of contents
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... SETI 3 R SETI © 2006 Integrated Electronic Solutions Pty Ltd. trading as Hendon Semiconductors, all rights reserved. 2007 May 28, Revision 1.0 voltage to overcome the higher voltage required to drive an LED. Using an external choke to provide the voltage boost, the flyback voltage on the choke can be used directly to drive ...
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PINNING INFORMATION 4.1 Pinning layout Fig.2 Pin configuration 5 QUICK REFERENCE DATA Unless otherwise specified all voltages are specified with respect to V operating input supply voltage range maximum output voltage (peak) maximum output load current (average) maximum output ...
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FUNCTIONAL DESCRIPTION 6.1 OM5448 function The OM5448 is an inductive boost converter IC designed to operate to a very low voltage. Using a bipolar process, it will operate down to a supply voltage of 1 volt, making it suitable ...
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Monostable time delay When the V trip level of the CE(SAT) output transistor is reached, and ON/OFF latch is switch to its OFF state. This initiates a time delay by ...
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CHARACTERISTICS 25°C; Voltages are specified with respect to V amb SYMBOL PARAMETER Power supply V supply voltage (operating) CC Supply current (pin standby supply current SUP(standby) I operating supply current SUP(run) ...
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APPLICATION INFORMATION 9.1 Circuit design considerations A series of circuit examples are suggested. These offer a number of application ideas for use of the OM5448. They have been chosen to illustrate the different ways in which the OM5448 can ...
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The value of the current setting resistor R1 must be chosen to give the required average LED current and hence brightness. The required value of R1, and the operating duty cycle will change depending on the forward voltage drop of ...
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LE D Curre ffic for OM54 4 8 wit h Whit diode E ffi 100 ...
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The third graph in figure 7 shows the efficiency against LED current for an amber LED. Both the pulsed circuit (figure 3) and the DC drive circuit (figure 4) are shown on this graph Curre ...
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Out put Curre sist or for wit h 1.2 V supply ( ...
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Fig.10 OM5448 LED drive circuit with switched light level using the R 9.5 Series and parallel LED connection Earlier application circuits have shown single LED drive. However the OM5448 is also suitable for driving multiple LEDs in either series or ...
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Fig.12 Parallel LED drive using the OM5448 (with current sharing resistors). In figure 12 4.7 ohm resistors have been used in series with each of the three parallel LEDs to force current sharing the voltage drop across ...
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Supply voltage sensitivity As the base drive to the output transistor in the OM5448 is set by the input current to the SETI pin, the resulting LED current is therefore dependent on the voltage across the SETI resistor R1. ...
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Fig.15 Simple stabilization circuit for LED current variation against supply voltage. Fig.16 LED current against supply voltage, showing stabilized and uncompensated curves (fig 15 & 4). 2007 May 28, Revision 1.0 Low Voltage LED Driver and Boost Converter 14 OM5448 ...
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LED drive temperature sensitivity The variation of LED current with temperature is shown in figure 17. LED Current (mA) 40.0 35.0 30.0 25.0 20.0 15.0 10.0 5.0 0.0 -50 -25 0 Fig.17 LED current against temperature. White LED, circuit ...
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Voltage boost power supply The OM5448 is suitable for providing a boosted higher voltage power supply from single or double cell battery circuits. The most simple boost power supply circuit is that shown in figure 18. Fig.18 Voltage boost ...
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Regulated boost power supply In the circuit of the regulated boost power supply in figure 19 the OM5448 provides drive to the output regulating circuit until the zener diode begins to conduct. When the zener diode conducts, and sufficient ...
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Fig.21 Regulated voltage multiplier boost power supply circuit using the OM5448. 9.13 Negative regulated power supply The circuit shown in figure 22 shows how the OM5448 can generate a regulated -5 volt supply from a single cell battery. The pulsed ...
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Fig.22 Negative regulated power supply from single cell supply using the OM5448. 2007 May 28, Revision 1.0 Low Voltage LED Driver and Boost Converter 19 OM5448 Product Specification ...
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... OM5448 SO23-5 plastic small outline package; 5 leads; body width 1.6 mm Other package options are available. Contact Hendon Semiconductors for details. For more information on packages, please refer to the document “Integrated Circuit Packaging and Soldering Information”, available from Hendon Semiconductors. 11 ESD CAUTION Electrostatic Discharge (ESD) sensitive device ...
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... Exposure to limiting values for extended periods may affect device reliability. Application information Where application information is given advisory and does not form part of the specification. 14 COMPANY INFORMATION HENDON SEMICONDUCTORS a trading name of INTEGRATED ELECTRONIC SOLUTIONS PTY. LTD. ABN 17 080 879 616 Postal address: Hendon Semiconductors ...
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... Life Support Applications Products of Hendon Semiconductors (Hendon) are not designed for use in life support appliances, devices or systems, where malfunction can result in personal injury. Customers using or selling Hendon products for use in such applications their own risk and agree to fully indemnify Hendon for any damages resulting from such improper use or sale. ...