LX1664 Microsemi Corporation, LX1664 Datasheet
LX1664
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LX1664 Summary of contents
Page 1
... VID4 VID4 Wide-Body SOIC Plastic DIP N 16-pin Note: All surface-mount packages are available in Tape & Reel. Append the letter "T" to part number. (e.g. LX1664CDT 11861 W A ESTERN LX1664/64A, LX1665/65A set by a DIP switch on the motherboard, or hardwired into the processor’ ...
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... LX1664/64A, LX1665/65A Smallest Package Size. The LX1664 is available in a narrow body 16-pin surface mount IC package for space sensitive appli- cations. The LX1665 provides the additional functions of Over Voltage Protection (OVP) and Power Good (PWRGD) output drives for applications requiring output voltage monitoring and protection functions ...
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... V = 12V, Out Freq = 200kHz DAC ) CC_CORE OUT I = 5mA PWRGD ( CC_CORE DAC Set by external resistors I = 0.5A using 0.5% resistors L Open Loop LX1664/1665 (A) Units Min. Typ. Max - LOAD - µs 1 µs 40 ppm 180 210 240 µ 0 ...
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... LX1664/64A, LX1665/65A * Nominal = DAC setpoint voltage with no adaptive output voltage positioning. Note: Adaptive Transient Voltage Output In order to improve transient response a 40mV offset is built into the Current Sense comparator. At high currents, the peak output voltage will be lower than the nominal set point, as shown in Figure 1 ...
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... I (A) OUT FIGURE 2 — Efficiency Test Results: Non-Synchronous Operation FIGURE 4 — Efficiency Test Results: Synchronous Operation, V Note: Non-synchronous operation not recommended for 12V operation, due to power loss in Schottky diode. LX1664/1664A, LX1665/65A 100 Output Set Point EFFICIENCY AT 3.1V EFFICIENCY AT 2.8V 75 EFFICIENCY AT 1 ...
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... REG Off-Time Controller DAC OUT 1.5V DAC Note: Pin numbers are correct for LX1665/1665A, 18-pin package. VID2 VID3 VID4 FIGURE 5 — LX1664/1665 Block Diagram PWM Latch DOM R Q Break Before Make 0.7V SYNC EN Comp OV Comp UV Comp LX1665/1665A ONLY Linear Op Amp * Not connected on LX1664/1664A ...
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... FET is replaced by a Schottky diode). Both power and signal ground of the device. Gate drive for top MOSFET. This pin is a separate power supply input for the top drive. Can be connected to a charge pump when only 12V is available. LX1664/1664A, LX1665/65A nd SB) input. rd SB) input. ...
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... I/O buffers, memory, chipset and other components. The output can be adjusted to any voltage between 1.5V and 3.6V in order to supply other (lower) power requirements on a mother- board. See section "Using the LX1664/1665 Devices" at the end of this data sheet. ). the fault condition must be 1 ...
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... V CC_CORE 4 VID0 VID0 5 VID1 VID1 6 VID2 VID2 7 VID3 VID3 8 VID4 VID4 16-pin Narrow Body SOIC FIGURE 6 — LX1664 In A Pentium / Socket 7 Single-Chip Power Supply Controller Solution (Synchronous 0.1µF U1 LX1664 INV TDRV 3 V GND CC_CORE 4 VID0 VID0 BDRV 5 VID1 ...
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... LX1664/64A, LX1665/65A C 3 0.1µ VID0 5 VID1 6 VID2 7 VID3 8 VID4 9 FIGURE 8 — VRM 8.2 (Pentium II / Deschutes) Reference Design With Loss-Less Current Sensing C 3 0.1µ VID0 5 VID1 6 VID2 7 VID3 8 VID4 9 FIGURE 9 — Full-Featured Pentium II Processor Supply With 12V Power Input ...
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... Ref Description Ω The LX1664/65 devices are very easy to design with, requiring only a few simple calculations to implement a given design. The following procedures and considerations should provide effec- tive operation for virtually all applications. Refer to the Appli- cation Information section for component reference designa- tors ...
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... The LX166x family offers two different comparator thresholds. The LX1664 & 1665 have a threshold of 100mV, while the LX1664A and LX1665A have a threshold of 60mV. The 60mV threshold is better suited to higher current loads, such as a Pentium II or Deschutes processor ...
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... S Current R S2 Sense V CS Comparator FIGURE 11 — Current Sense Circuit LX1664/1664A, LX1665/65A CURRENT LIMIT The current flowing through the inductor is a triangle wave. If the sensor components are selected such that: L The voltage across the capacitor will be equal to the current flowing through the resistor, i.e. ...
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... LX1664/64A, LX1665/65A CURRENT LIMIT (continued) In cases where large that the trip point current would L be lower than the desired short-circuit current limit, a resistor (R can be put in parallel with shown in Figure 11. The selection S of components is as follows (Required (Actual) ...
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... LINEAR REGULATOR Referring to the front page Product Highlight, a schematic is presented which uses a MOSFET as a series pass element for a linear regulator. The MOSFET is driven by the LX1664 controller, and down-converts a +5V or +3.3V supply to the desired V level, between 1.5 & 3.5V, as determined by the feedback resistors. The current available from the Linear regulator is dictated by the supply capability, as well as the MOSFET ratings, and will typically lie in the 3-5 ampere range ...
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... LX1664/64A, LX1665/65A LINEAR REGULATOR (continued) TABLE 6 - Resistors Settings for Linear Regulator Output Voltage Ω Ω Ω Ω Ω Capacitor Selection Referring to the Product Highlight schematic on the front page, the standard value to use as the linear regulator stage output capacitor is on the order of 330µF. This provides sufficient hold-up for all expected transient load events in memory and I/O circuitry ...
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... LinFinity. Product processing does not necessarily include testing of all parameters. Linfinity reserves the right to change the configuration and performance of the product and to discontinue product at any time. LX1664/1664A, LX1665/65A (continued) Layout Assistance Please contact Linfinity’ ...