lx1669 Microsemi Corporation, lx1669 Datasheet
lx1669
Related parts for lx1669
lx1669 Summary of contents
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... NOTE: For current data & package dimensions, visit our web site: http://www.linfinity.com. 5V 12V C8 C3 1µF 1µF R3 10k PWRGD Note: All surface-mount packages are available in Tape & Reel, append the letter "T" to part number. (i.e. LX1669CDT Copyright © 1999 11861 W A Rev. 1.0 4/99 ESTERN P ...
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... LX1669 LUT E MAXIM UM RAT INGS 12V Supply Voltage (V ) .................................................................................. 18V CC12 5V Supply Voltage (V ) ....................................................................................... 7V CC5 Output Drive Peak Current Source (500ns) ....................................................... 1.0A Output Drive Peak Current Sink (500ns) ........................................................... 1.0A Input Voltage (SS, VID[0:4]) ................................................................... -0. Operating Junction Temperature .................................................................... 150° ...
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... SET CORE OUT2 I = 4mA PWRGD ( rising CORE SET CORE V = 2.0V OVP V Internally pulled thru 30k IL CC5 V IH LX1669 5V 12V 25°C.) CC5 CC12 LX1669 Min. Typ. Max. V 3.5V 25° CORE A -1.5 1.5 2.4 250 -0.3 -1 100 100 100 10 11 0.1 0.2 3.9 4.2 4.6 ...
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... LX1669 P Table 1 - Adaptive Transient Voltage Output VID4 Nominal = DAC setpoint voltage with no adaptive output voltage positioning. ...
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... Comp PWM I RESET Set V RESET Error Comp Off-Time Hiccup Control Hiccup FIGURE 3 — Block Diagram LX1669 EFFICIE NCY A T 3.1V EFFICIE NCY A T 2.8V EFFICIE NCY (A) OUT FIGURE 2 — Efficiency Test Results: ...
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... LX1669 P Pin Pin Number Designator Description 1 TDRV Gate drive to the top FET +12V supply for the gate drivers. If 12V is not available in the application, a bootstrap circuit is required CC12 to create the biasing voltage for the FET gate drivers. ...
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... POWER UP and INITIALIZATION At power up, the LX1669 monitors the supply voltage to both the +5V and the +12V pins (there is no special requirement for the sequence of the two supplies). Before both supplies reach their ...
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... LX1669 P OVER-CURRENT PROTECTION (OCP) and HICCUP The over-current protection function is tripped when the induc- tor current exceeds its maximum limit. The current is sensed with a resistor in series with the inductor. When the voltage ...
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... LX1669 Bill of Materials (Refer to Product Highlight) Part Number / Manufacturer LX1668 - LinFinity MV-GX Sanyo MV-GX Sanyo ) IRL3102/3103, International Rectifier ) ...
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... LX1669 5µH, L OUT OUTPUT INDUCTOR The output inductor should be selected to meet the requirements of the output voltage ripple in steady-state operation and the inductor current slew-rate during transient. The peak-to-peak output voltage ripple is: ...
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... V , allowing a higher ESR value and EX reducing the cost of the output capacitor. The positioning voltage is 40mV (peak), using the LX1669, and the transient tolerance is 100mV, resulting Electrolytic capacitors can be used for the output capacitor, but are less stable with age than tantalum capacitors. As they age, their ESR degrades, reducing the system performance and increasing the risk of failure ...
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... LX1669 P CURRENT LIMIT (continued) There are several alternative types of sense resistor. The surface-mount metal “staple” form of resistor has the advantage of exposure to free air to dissipate heat and its value can be controlled very tightly ...
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... S2 S more information. OUTPUT ENABLE The LX1669 FET driver outputs are driven to ground by pulling the soft-start pin below 0.5V. PROGRAMMING THE OUTPUT VOLTAGE The output voltage is set by the DAC with a 5-bit digital voltage- identification (VID) code input (see Table 1). The DAC input is designed to be compatible with digital circuits ...
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... LX1669 PGND Input Decoupling Capacitors Ensure that capacitors C8 and C3 are placed as close to the IC as possible to minimize the effects of noise on the device. Layout Assistance Please contact Linfinity’ ...