L8401G-R16-R datasheet(4/5 Pages) UTC

4 / 5 page

L8401

Preliminary

LINEAR INTEGRATED CIRCUIT

UNISONICTECHNOLOGIESCO.,LTD

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www.unisonic.com.tw

QW-R123-018.a

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TYPICAL APPLICATION CIRCUIT

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APPLICATIONS INFORMATION

It is application circuit of UTC L8401 in figure 2, the bias circuits is stable fully in -40°C ~80°C.

CNB and CSUB are used to generated the negative supply on pin CSUB (about -2.5V), which can be used to power

other external circuits, but it is low load current is noticeable.

C1 and C2 are used to suppress noise or RF interference in each stage of the IC or other external circuits in

application circiut system. Value of C1 and C2 could be used in 1nF to 100nF as design dependent.

RCAL1 and RCAL2 are used to set the drain current of FETs 1 & 2 and FETS 3 & 4. If the same drain current is

required for all FETs on UTC L8401, then the pin RCAL1 and RCAL2 can be connected to GND through only one res of

half normal value.

There are full protection for external FETs on chip: The gate output voltage is limitted in -2.5V~0.7V in any

conditions including powerup and powerdown transients; If the negative bias generator be shorted or overloaded, the

drain supply to FETs is shut down to avoid damage to the FETs by excessive drain current.

The fig.3 is typical applications of UTC L8401 in LNB.

L8401G-R16-R Datasheet(PDF) 4 Page - Unisonic Technologies