XC6376/6377

Series

587

5

6. EXT / 1, EXT / 2 Pins

As the EXT / 1 and EXT / 2 pins are provided, external transistor drives and various application circuits can be handled.

EXT / 1 follows the same timing pattern as a P-channel power MOSFET ("L" in the ON mode) whereas EXT / 2 functions in a 100 nsec

blank clock timing pattern (N.B. EXT / 2 changes from "H to L" 100 nsec before EXT /1 but 100 nsec after EXT / 1 with "L to H" changes.)

e.g.

The drawing of large output currents can be handled by connecting an external, low ON resistance, P-ch power MOSFET.

application circuit examples provided.

The EXT /1 pin can be driven to a gate capacitance of up to 1000pF.

7. U. V. L. O Circuit

EXT /2 will be "H" . (If using an external transistor, the transistor will be set to OFF.)

Note that this function is not available with externally set-up output voltage types (FB).

Sudden current changes at ground or power supply that are common to step-down DC/DC converters during switching may cause the IC's

operations to become unstable depending upon the degree to which the IC's power supply voltage changes, which in turn is affected by the

wiring's impedance level.

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