ZNBG3115Q20 datasheet(7/14 Pages) ZETEX

Part #	ZNBG3115Q20

Description	FET BIAS CONTROLLER WITH POLARISATION SWITCH AND TONE DETECTION

Download	14 Pages

Scroll/Zoom	100%

Manufacturer	ZETEX [Zetex Semiconductors]

Direct Link	http://www.diodes.com/

Logo

7 / 14 page

ZNBG3115

ZNBG3116

ISSUE 1 - JUNE 2001

7

FUNCTIONAL DIAGRAM

FUNCTIONAL DESCRIPTION

The ZNBG devices provide all the bias requirements for external FETs, including the generation of the negative

supply required for gate biasing, from the single supply voltage.The diagram above shows a single stage from

the ZNBG series. The ZNBG3115/16 contains 3 such stages. The negative rail generator is common to both

devices.

The drain voltage of the external FET QN is set by the ZNBG device to its normal operating voltage. This is

determined by the on board VD Set reference, for the ZNBG3115 this is nominally 2.2 volts whilst the ZNBG3116

provides nominally 2 volts.

The drain current taken by the FET is monitored by the low value resistor ID Sense. The amplifier driving the gate

of the FET adjusts the gate voltage of QN so that the drain current taken matches the current called for by an

external resistor RCAL.

Since the FET is a depletion mode transistor, it is often necessary to drive its gate negative with respect to ground

to obtain the required drain current. To provide this capability powered from a single positive supply, the device

includes a low current negative supply generator. This generator uses an internal oscillator and two external

capacitors, CNB and CSUB.

Similar Part No. - ZNBG3115Q20

Manufacturer	Part #	Datasheet	Description
Zetex Semiconductors	ZNBG3115	606Kb / 15P	FET BIAS CONTROLLER WITH POLARISATION SWITCH AND TONE DETECTION
Diodes Incorporated	ZNBG3115	614Kb / 15P	FET BIAS CONTROLLER WITH POLARISATION
Zetex Semiconductors	ZNBG3115	606Kb / 15P	FET BIAS CONTROLLER WITH POLARISATION SWITCH AND TONE DETECTION

Manufacturer	Part #	Datasheet	Description
Unisonic Technologies	UTCL8115	174Kb / 13P	FET BIAS CONTROLLER WITH POLARISATION SWITCH AND TONE DETECTION
Zetex Semiconductors	ZNBG3113	684Kb / 17P	FET BIAS CONTROLLER WITH POLARISATION SWITCH AND TONE DETECTION
	ZNBG3210	387Kb / 16P	FET BIAS CONTROLLER WITH POLARISATION SWITCH AND TONE DETECTION
	ZNBG3110	657Kb / 16P	FET BIAS CONTROLLER WITH POLARISATION SWITCH AND TONE DETECTION
	ZNBG3115	606Kb / 15P	FET BIAS CONTROLLER WITH POLARISATION SWITCH AND TONE DETECTION
Diodes Incorporated	ZNBG3211Q20TC	399Kb / 16P	FET BIAS CONTROLLER WITH POLARISATION SWITCH AND TONE DETECTION ISSUE 2 - FEBRUARY 2000
Aimtron Technology	AT1512	351Kb / 11P	FET BIAS CONTROLLER AND TONE DETECTION
Aimtron Technology	AT1511	276Kb / 9P	FET BIAS CONTROLLER AND TONE DETECTION
Diodes Incorporated	ZNBG3113	698Kb / 17P	FET BIAS CONTROLLER WITH POLARISATION
Diodes Incorporated	ZNBG3210	399Kb / 16P	FET BIAS CONTROLLER WITH POLARISATION