lx1663 Microsemi Corporation, lx1663 Datasheet
lx1663
Related parts for lx1663
lx1663 Summary of contents
Page 1
... Over-Voltage Protection and Power Good Flag. The OVP output in the LX1663 & LX1663A can be used to drive an SCR crowbar circuit to protect the load in the event of a short-circuit of the main MOSFET. The LX1663 & LX1663A also have a logic- level Power Good Flag to signal when the output voltage is out of specified limits ...
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... All of the above assume no ambient airflow 2 (Note 1) , VID0-VID4) ........................................... -0. 65°C/W JA 120°C θ PACKAGE — 14-Pin LX1662/1662A (Top View) N PACKAGE — 16-Pin LX1663/1663A (Top View) D PACKAGE — 14-Pin LX1662/1662A (Top View) D PACKAGE — 16-Pin LX1663/1663A (Top View) ...
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... SD SS Sat Voltage V OL Supply Current Section Dynamic Operating Current I CD Power Good / Over-Voltage Protection Section (LX1663 Only) Lower Threshold Hysteresis Power Good Voltage Low Over-Voltage Threshold OVP Sourcing Current LX1662/62A, LX1663/63A ≤ 70°C. Test conditions 12V 25°C. Use Application Circuit.) ...
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... LX1662/62A, LX1663/63A * 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. LX1662/62A, LX1663/63A 100 Output Set Point EFFICIENCY AT 3.1V EFFICIENCY AT 2.8V 75 EFFICIENCY AT 1 ...
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... FIGURE 5 — Block Diagram PWM Latch DOM R Q Break Before Make 0.7V SYNC EN Comp OV Comp UV Comp LX1663/1663A ONLY Note: Pin numbers are correct for LX1663/1663A, 16-pin package. * Not connected on the LX1662/1662A. ** 60mV in LX1662A & LX1663A TDRV 15 GND 14 BDRV OV* ...
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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. LX1662/62A, LX1663/63A nd SB) input. rd SB) input. ...
Page 8
... The controller is inherently protected from an over-voltage condition due to its constant OFF-time architecture. However, should a failure occur at the power switch, an over-voltage drive pin is provided (on the LX1663 only) which can drive an external SCR crowbar (Q must be removed and power recycled for the LX1663 to resume normal operation (See Figure 9) ...
Page 9
... INV 3 V CC_CORE 4 VID0 VID0 5 VID1 VID1 6 VID2 VID2 7 VID3 VID3 VID4 14-pin, Narrow Body SOIC FIGURE 7 — LX1662 In A Non-Synchronous Pentium / Socket 7 Power Supply Application LX1662/62A, LX1663/63A 12V 1µH 6.3V 1500µ 1µ TDRV 1 IRL3102 ...
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... LX1662/62A, LX1663/63A C 3 0.1µ VID0 5 VID1 6 VID2 7 VID3 8 VID4 FIGURE 8 — Pentium II Processor Application With OVP, Power Good And Loss-Less Current Sensing (Synchronous 0.1µF LX1663 INV 3 V CC_CORE 4 VID0 VID0 5 VID1 VID1 6 VID2 VID2 7 VID3 VID3 8 VID4 ...
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... S OUT Where I is fixed at 200µA and f is the switching frequency DIS S (recommended to be around 200kHz for optimal operation and component selection). LX1662/62A, LX1663/63A Part Number / Manufacturer When using a 5V input voltage, the switching frequency (f can be approximated as follows: I DIS C = 0.621 * f T ...
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... The LX166x family offers two different comparator thresholds. The LX1662 & 1663 have a threshold of 100mV, while the LX1662A and LX1663A 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 LX1662/62A, LX1663/63A 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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... LX1662/62A, LX1663/63A 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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... 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. LX1662/62A, LX1663/63A LX166x All of these traces should be made as wide and thick as possible, in order to minimize resistance and hence power losses ...