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Details, datasheet, quote on part number:ZNBG3000Q16
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Datasheet text preview:
FET BIAS CONTROLLER
ISSUE 1- AUGUST 1998 DEVICE DESCRIPTION
The ZNBG series of devices are designed to meet the bias requirements of GaAs and H EMT FETs commonly used in satellite receiver LNBs, PMR, cellular telephones etc. with a minimum of external components. With the addition of two capacitors and a resistor the devices provide drain voltage and current control for 3 external grounded s o u r c e FETs, generating the regulated negative rail required for FET gate biasing whilst operating from a single supply. This negative bias, at -3 volts, can also be used to supply other external circuits. The ZNBG3000/1 contains three bias stages. A single resistor allows FET drain current to be set to the desired level. The series also offers the choice of drain voltage to be set for the FETs, the ZNBG3000 gives 2.2 volts drain whilst the ZNBG3001 gives 2 volts. 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. T h e s e ensure RF stability and minimal injected noise.
ZNBG3000 ZNBG3001
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. In order to protect the external FETs the circuits have been designed to ensure that, u n d e r any conditions including power up/down transients, the gate drive from the bias circuits cannot exceed the range -3.5V to 0.7V. Furthermore if the negative rail e x p e r i e n c e s a fault condition, such as overload or short circuit, the drain supply to the FETs will shut down avoiding excessive current flow. The ZNBG3000/1 are available in QSOP16 packages for the minimum in devices size. Device operating temperature is -40 to 70°C t o suit a wide range of environmental conditions.
FEATURES
APPLICATIONS
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Provides bias for GaAs and HEMT FETs Drives up to three FETs Dynamic FET protection Drain current set by external resistor Regulated negative rail generator requires only 2 external capacitors Choice in drain voltage Wide supply voltage range QSOP surface mount package
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Satellite receiver LNBs Private mobile radio (PMR) Cellular telephones Single in single out C Band LNB
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ZNBG3000 ZNBG3001
ABSOLUTE MAXIMUM RATINGS
Supply Voltage Supply Current Drain Current (per FET) (set by RCAL1 and RCAL2) Output Current Operating Temperature Storage Temperature -0.6V to 15V 100mA 0 to 15mA 100mA -30 to 70°C -40 to 85°C Power Dissipation (Tamb= 25°C) QSOP16 500mW
ELECTRICAL CHARACTERISTICS TEST CONDITIONS (Unless otherwise stated): Tamb= 25°C,VCC=5V,ID=10mA (RCAL1 =33k) )
SYMBOL PA RAMETER V CC I CC V SUB Supply Voltage Supply Current Substrate Voltage (Internally generated) Output Noise Drain Voltage Gate Voltage Oscillator Freq. Output Current Range Current Current Change ID V ID T VD with VCC with Tj Voltage VCC=5 to 12V Tj=-30 to +70°C ZNBG3000 ID1 to ID3=10mA ZNBG3001 VCC= 5 to 12V Tj = -30 to +70°C 2 1.8 0. 5 0. 05 2. 2 2 0. 5 50 2.4 2.2 %/V %/°C V V %/V ppm Set by RCAL1 ID1 to ID3=0 ID1 to ID3=10mA ISUB= 0 ISUB= -200µA CG=4.7nF, CD=10nF CG=4.7nF, CD=10nF 2 00 0 8 10 33 0 -3. 5 -2.8 CONDITIONS Min 5 LIMITS Typ Max 12 10 40 -2 -2 0.0 2 0.0 05 800 15 12 V mA mA V V Vp kp k Vp kp k kHz mA mA UNI TS
E ND E NG fO IDO ID
DRAIN CHARACTERISTICS
Voltage Change VDV VDT with VCC with Tj
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ZNBG3000 ZNBG3001
SYMBOL PARAMETER CONDITIONS Min LIMITS Typ Max 2000 µA UNI TS
GATE CHARACTERISTICS
IGO VOL Output Current Range Output Voltage Output Low ID1 to ID3=12mA IG1 to IG3=0 ID1 to ID3=12mA IG1 to IG3= -10µA VO H
Notes: 1. The negative bias voltages specified are generated on-chip using an internal oscillator. Two external capacitors, CNB and CSUB, of 47nF are required for this purpose. 2. The characteristics are measured using an external reference resistors RCAL1 of value 33k wired from pin RCAL1 to ground.
-30
-3.5 -3.5 0 .4
-2 -2 1
V V V
Output High
ID1 to ID3= 8mA IG1 to IG3= 0
3. Noise voltage is not measured in production. 4. Noise voltage measurement is made with FETs and gate and drain capacitors in place on all outputs. CG, 4.7nF, are connected between gate outputs and ground, CD, 10nF, are connected between drain outputs and ground.
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