ZABG4002JA16TC

NOT RECOMMENDED FOR NEW DESIGN USE ZABG4003 ZABG4002 LOW POWER 4 STAGE FET LNA BIAS CONTROLLER Summary The ZABG4002 is a four stage depletion mode FET bias controller intended primarily for satellite Low Noise Blocks (LNBs), but its also suitable for other LNA applications such as those in found in PMRs and microwave links. The ZABG4002 provides each FET with an independent protected negative gate voltage and positive drain voltage with user programmable drain current. Combining an advanced IC process and packaging techniques, the ZABG4002 helps minimise power consumption, component cost and PCB area whilst enhancing overall reliability. Features Pin Assignments Four Stage FET Bias Controller (Top View) Operating Range of 3.0V to 8.0V Low Quiescent Supply Current, 1.2mA Typical FET Drain Voltages Set at 2.0V FET Drain Current Selectable from 0 to 15mA D2 G3 Switchable FETs for Power Management G2 ZABG Allows First and Second Stage FETs to Be Run at Different D4 (Optimum) Drain Currents V 4002 CC G4 FET Drain Voltages and Currents Held Stable Over Temperature GND R CAL1 and V Variations CC FETs Protected against Overstress during Power-up and Power- down Internal Negative Supply Generator Allowing Single Supply (Bottom View) Operation (Available for External Use) Low External Component Count Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2) Halogen and Antimony Free. Green Device (Note 3) C SUB Applications Twin LNBs Quad LNBs QFN1633 US LNBs Microwave Links PMR and Cellular Telephone Systems Notes: 1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS), 2011/65/EU (RoHS 2) & 2015/863/EU (RoHS 3) compliant. 2. See NOT RECOMMENDED FOR NEW DESIGN USE ZABG4003 ZABG4002 Device Description The ZABG series of devices are designed to meet the bias requirements of GaAs and HEMT FETs commonly used in satellite receiver LNBs with a minimum of external components whilst operating from a minimal voltage supply and using minimal current. The ZABG4002 provides four FET bias stages, arranged in two pairs of two. Resistors connected to pins R and R set the FET drain CAL1 CAL2 currents of each pair over the range of 0 to 15mA, allowing input FETs to be biased for optimum noise and amplifier FETs for optimum gain. Drain voltages of all stages are set at 2.0V. The drain supplies are current limited to approximately 5% above the operating currents set by the R resistors. CAL As an additional feature the R pins can also be used as logic inputs to disable pairs of FETs as part of a power management scheme or simply CAL an alternative to LNA switching. Driven to a logic high (>3.0V), the inputs disable their associated FET bias stages by switching gate feeds to -2.5V and drain feeds open circuit. Depletion mode FETs require a negative voltage bias supply when operated in grounded source circuits. The ZABG4002 includes an integrated low noise switched capacitor DC-DC converter generating a regulated output of -2.5V to allow single supply operation. To facilitate the design of efficient low voltage 3.3V LNB systems and to maintain compatibility with higher voltage legacy designs, the ZABG4002 is capable of operating within the supply of 3.0V to 8V. These devices are unconditionally stable over the full working temperature with the FETs in place, subject to the inclusion of the recommended gate and drain capacitors. These ensure RF stability and minimal injected noise. It is possible to use less than the devices full complement of FET bias controls, unused drain and gate connections can be left open circuit without affecting operation of the remaining bias circuits. To protect the external FETs the circuits have been designed to ensure that, under any conditions including power up/down transients, the gate drive from the bias circuits cannot exceed -3V. Additionally each stage has its own individual current limiter. Furthermore if the negative rail experiences a fault condition, such as overload or short circuit, the drain supply to the FETs will shut down avoiding excessive current flow. To minimise PCB space ZABG4002 is packaged in the 16 pin 3mm x 3mm QFN1633 package. Device operating temperature is -40C to +85C to suit a wide range of environmental conditions. 2 of 7 ZABG4002 January 2019 Diodes Incorporated www.diodes.com Document number: DS32047 Rev. 3 - 3