FUNCTIONAL DIAGRAM

FUNCTIONAL DESCRIPTION

The ZNBR 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 ZNBR series. The ZNBR4000/1 contains 4 such

stages, the ZNBR6000/1 contains 6. The negative rail generator is common to all devices.

2.2 volts whilst the ZNBR4001/6001 provides nominally 2 volts.

sets the drain current of FETs 2, 3, 5 and 6.

Since the FET is a depletion mode transistor, it is usually 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

ZNBR4000

ZNBR4000 ZNBR4001

ZNBR6000 ZNBR6001

5