HMC981 v00.0611 ACTIVE BIAS CONTROLLER BIAS CONTROLLERS - CHIP Typical Applications Features * Military & Space Automatic Gate voltage adjustment (No Calibration required) Supply Voltage: 4V to 12V * Test Instrumentation Digital Voltage: 3.3V to 5V * Fiber Optic Modulator Driver Biasing * CATV Laser Driver Biasing Controls both Enhancement and Depletion type devices * Cellular Base Station Adjustable Drain Current up to 200mA * Wireless Infrastructure Equipment Sink/Source Gate Current Capability * Microwave Radio & VSAT Optional Internal negative voltage generation that can be disabled to use external negative rail Fast Enable/Disable Trigger-out Output for Daisy Chain Power-Up and Power-Down Sequencing Functional Diagram General Description HMC981 is an active bias controller that automatically adjusts the gate voltage of an external amplifier to achieve constant bias current. It can be used to bias any enhancement and depletion type amplifiers operating in Class-A regime with Drain voltages from 4V to 12V and drain currents up to 200mA, offering a complete biasing solution. HMC981 achieves excellent bias stability over supply, temperature and process variations, and eliminates the required calibration procedures usually employed to prevent RF performance degradation due to such variations. All data shown herein is taken with appropriate probes. 1 For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com Application Support: Phone: 978-250-3343 or apps@hittite.com HMC981 v00.0611 ACTIVE BIAS CONTROLLER Electrical Specifications, TA = +25C, VDD=8V, VDIG= 3.3V, Depletion Master Unless Otherwise Noted Symbol Conditions Vdd IDD VDD = 8V VDIG Quiescent Current IDIG Typ. 4 VDD = 4V VDD Quiescent Current Min. Max. 12 Units V EN = VDIG 7 mA EN = GND 3 mA EN = VDIG 7.5 mA EN = GND 4 mA VDIG= 3.3 V 3 mA VDIG= 5 V 5 mA Negative Voltage Output VNEG -2.5 V Oscillator Frequency FOSC 300 kHz Voltage Reference VREF 1.42 V Enable Input Threshold Switch Input Threshold Short Circuit Disable Input Threshold ENTHRS SWTHRS DSCTHRS Vinlow Vinhigh 1 1.4 V Vinlow Vinhigh 1 1.4 1 1.4 SW=GND 20 SW=VDIG 80 V V Vinlow Vinhigh V V V VDRAIN Characteristics DRAIN Current Adjustment Range DRAIN Current Change Over Digital Voltage DRAIN Current Change Over Temperature DRAIN Range VDRAIN Change Over Temperature IDRAIN IDRAINV VDRAIN set to 8V, IDRAIN set to 160 mA VDRAIN VDRAIN 80 200 mA 0.4 %/V 0.02 %/C 4 VDRAIN set to 8V, IDRAIN set to 160 mA mA 12 BIAS CONTROLLERS - CHIP Parameter Supply Voltage V 1.5 %/C -2.5 V VNEG Characteristics Negative Voltage Output VNEG VNEG Current Sink INEG VDD= 4V 0 8 mA VDD= 8V 0 15 mA 0.8 mA VGATE Characteristics GATE Current Supply IG -0.8 VGATE Low Level VG_MIN VNEG V VGATE High Level VG_MAX VNEG+4.5 V VG2 Characteristics VG2 Current Supply IG2 VG2 Adjustment Range VG2 VG2<1.5V -0.1 0.1 mA VG2>1.5V -1 1 mA 1 VDD-1.3 V 3.3 5 V VDIG Characteristics Adjustment Range VDIG Quiescent Current VDIG IDIG VDD= 8 V, 3 mA SW= GND 10 Ohm SW=VDIG 5 Ohm VDIG=EN =3.3 V SW Characteristics Internal Switch Resistance RDS_ON For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com Application Support: Phone: 978-250-3343 or apps@hittite.com 2 HMC981 v00.0611 ACTIVE BIAS CONTROLLER 8.5 6 8 VDRAIN (V) VDRAIN (V) Load Regulation @ VDD=8V, SW=VDIG=3.3V 6.5 5.5 5 4.5 30 7.5 7 +25C +85C -55C 20 +25C +85C -55C 40 50 60 70 6.5 80 80 100 120 55 -2.45 54 -2.47 VNEG (V) 53 52 +25C +85C -55C 50 3.3 3.7 No load condition -2.49 -2.51 4.1 4.5 -2.55 4.9 4 6 -2.4 VNEG (V) VNEG (V) -2.4 -2.5 +25C +85C -55C 4 6 10 12 VNEG Load Regulation @ VDD=12V -2.3 -2.6 8 SUPPLY VOLTAGE (V) -2.3 2 200 -2.53 VNEG Load Regulation @ VDD=4V 0 180 +25C +85C -55C VDIG (V) -2.7 160 VNEG Line Regulation vs. Supply Voltage IDRAIN vs. VDIG[1][2] 51 140 IDRAIN (mA) IDRAIN (mA) IDRAIN (mA) BIAS CONTROLLERS - CHIP Load Regulation @ VDD=6V, VDIG=3.3V, SW=GND 8 INEG (mA) -2.5 +25C +85C -55C -2.6 10 -2.7 0 4 8 12 16 INEG (mA) [1] IDRAIN is set to 53 mA [2] HMC465LP5 is used as external amplifier 3 For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com Application Support: Phone: 978-250-3343 or apps@hittite.com HMC981 v00.0611 ACTIVE BIAS CONTROLLER 8 6 6 4 4 2 0 -2 -4 2 4 6 8 EN VDRAIN VG2 VNEG VGATE -6 -8 12 -8 0 0 -2 -4 EN VDRAIN VG2 VNEG VGATE -6 2 10 12 14 Power Up Waveform 20 8 VDD VDRAIN VDIG VG2 VNEG VGATE 4 VDD VDRAIN VDIG VG2 VNEG VGATE 6 VOLTAGE (V) 6 VOLTAGE (V) 18 Shutdown Waveform 8 2 0 4 2 0 -2 -2 -4 -4 10 20 30 TIME (ms) 40 0 50 VNEG Load Transient VDD=4V 20 40 60 TIME (ms) 80 100 VNEG Load Transient VDD=6V -0.8 20 -1.3 10 -2.3 -10 15 -2.425 10 -2.45 5 -2.475 0 -5 -2.5 -10 -2.525 -20 -2.8 0 0.5 1 TIME (ms) 1.5 2 INEG (mA) 0 INEG (mA) -1.8 -2.4 VNEG (V) 0 VNEG (V) 16 TIME (ms) TIME (ms) BIAS CONTROLLERS - CHIP Disable Waveform 8 VOLTAGE (V) VOLTAGE (V) Enable Waveform -15 -2.55 0 0.5 1 1.5 2 TIME (ms) For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com Application Support: Phone: 978-250-3343 or apps@hittite.com 4 HMC981 v00.0611 ACTIVE BIAS CONTROLLER 5 VG2 Load Regulation @ VDD=6V 1 5 0.5 4.5 4 0 3.5 -0.5 VG2 (V) VGATE (V) BIAS CONTROLLERS - CHIP VGATE Load Regulation @ VDD=6V -1 -1.5 -2 -3 -1.25 -1 -0.75 -0.5 -0.25 0 0.25 IG (mA) 0.5 0.75 1 2 1.5 +25C +85C -55C -2.5 3 2.5 1 VG2=0.9V VG2=1.78V VG2=2.74V VG2=3.71V 0.5 1.25 0 -2 -1.5 -1 -0.5 0 0.5 1 1.5 IG2 (mA) For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com Application Support: Phone: 978-250-3343 or apps@hittite.com 2 HMC981 v00.0611 ACTIVE BIAS CONTROLLER VDD 12V VG2_CONT, VDRAIN -0.5V to VDD + 0.5V SW, EN, CP_OUT, VGATEFB, VNEGFB, TRIG_OUT, DISBL_SC, ISENSE -0.5V to VDIG + 0.5V VDIG 5.5V VNEG -4V to GND VG2 -0.5V to VDD + 0.5V Junction Temperature 125 C Continuous Pdiss (T = 85 C) (Derate 19.19 mW/C above 85 C) 0.77 Watts ELECTROSTATIC SENSITIVE DEVICE OBSERVE HANDLING PRECAUTIONS Thermal Resistance (RTH) (Junction to package bottom) 52.1 C/W Storage Temperature -65 to +150 C Operating Temperature -55 to +85 C ESD Sensitivity (HBM) Class 1B Note that there are two different voltage domains on HMC981; a high voltage domain Vdd, and a low voltage domain VDIG. Take necessary precautions not to violate ABS MAX ratings of each subdomains. NOTES: 1. ALL DIMENSIONS IN INCHES [MILLIMETERS] 2. DIE THICKNESS IS 0.010 (0.254) 3. TYPICAL BOND PAD IS 0.0039 SQUARE 4. BOND PAD METALLIZATION: ALUMINUM 5. NO BACKSIDE METAL 6. NO CONNECTION REQUIRED FOR UNLABELED BOND PADS 7. OVERALL DIE SIZE IS .002 Outline Drawing For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com Application Support: Phone: 978-250-3343 or apps@hittite.com BIAS CONTROLLERS - CHIP Absolute Maximum Ratings [1] 6 HMC981 v00.0611 ACTIVE BIAS CONTROLLER BIAS CONTROLLERS - CHIP Pad Descriptions 7 Pad Number Function Description 1, 5, 8, 10, 13, 15, 20, 23, 25, 26, Die Bottom GND These pads and the die bottom must be connected to a high quality RF/DC ground. 2 EN Enable pad. System is enabled when Ven is HIGH (VDIG). If left floating, Ven defaults to HIGH (enabled). 3 SW Internal switch resistance control pad. If left floating, VSW defaults to HIGH. 12 DISBLSC Disables short circuit lock down when pulled to ground. Leave it floating to enable short circuit lock down. 4 VG2CONT Control voltage of the VG2. Use a resistor divider between VDD and GND to set the voltage. VG2 is typically 1.3V lower than the VG2CONT 19 VG2 Second gate control. 6-7, 29-30 VDD, VDIG Bias supply pan. Connect supply voltage to this pad with appropriate filtering. 9 VREF 1.5V reference voltage. 0.1uF or greater capacitor to GND is needed for noise filtering. 11 ISENSE To adjust the bias current of the external amplifier connect a resistor (Rsense) from ISENSE pad to GND. Use Eqn.2 to determine the required Rsense value. Interface Schematic For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com Application Support: Phone: 978-250-3343 or apps@hittite.com HMC981 v00.0611 ACTIVE BIAS CONTROLLER Pad Descriptions (Continued) Function Description 14 TRGOUT Trigger out signal. Generates a HIGH (3.5V) signal when the active bias system stabilizes. This signal can be used to trigger next device (ENABLE) if more than one HMC981 is used in a daisy chain. 16, 17 VDRAIN Drain voltage. Should be connected to the supply terminal of the external amplifier. A minimum 100 nF capacitor has to be placed close to the external amplifier to improve load regulation. VGATE Gate Control pad for external amplifier. Connect to the gate (base) of the external amplifier. In order to guarantee stability,a 10F capacitor should be connected between the gate (base) terminal of the external amplifier and GND as close to the amplifier as possible. 21 VNEG Negative input to the chip. Should be supplied with CPOUT when negative voltage generator is enabled, or connect to external VSS when negative voltage generator is enabled. For detailed usage please refer to the "Negative Voltage Generator" section. 22 VNEGFB Feedback (Control) pad for Negative Voltage Generator Charge Pump. Float to activate the negative voltage generator / Sort to GND to disable the negative voltage generator. 24 VGATEFB Control pad for VGATEFB. Float VGATEFB when a depletion mode transistor is biased. Selects the mode of operation along with VNEGFB pad. For detailed usage please refer to the Table 2. 27, 28 CPOUT Negative voltage generator charge pump output. Negative voltage generator needs a flying capacitor, a reservoir capacitor and two diodes to operate. Please refer to the application schematic for more info. 18 Interface Schematic For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com Application Support: Phone: 978-250-3343 or apps@hittite.com BIAS CONTROLLERS - CHIP Pad Number 8 HMC981 v00.0611 ACTIVE BIAS CONTROLLER BIAS CONTROLLERS - CHIP Application Circuit Notes: [1] Adjust R10 with respect to equation (2). 9 For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com Application Support: Phone: 978-250-3343 or apps@hittite.com HMC981 v00.0611 ACTIVE BIAS CONTROLLER Mounting & Bonding Techniques for MMICs The die should be attached directly to the ground plane with epoxy (see HMC general Handling, Mounting , Bonding Note). Follow these precautions to avoid permanent damage. Storage: All bare die are placed in either Waffle or Gel based ESD protective containers, and then sealed in an ESD protective bag for shipment. Once the sealed ESD protective bag has been opened, all die should be stored in a dry nitrogen environment. Cleanliness: Handle the chips in a clean environment. DO NOT attempt to clean the chip using liquid cleaning systems. Static Sensitivity: Follow ESD precautions to protect against ESD strikes. Transients: Suppress instrument and bias supply transients while bias is applied. Use shielded signal and bias cables to minimize inductive pick-up. General Handling: The chip may be handled by a vacuum collet or with a sharp pair of tweezers. Mounting Epoxy Die Attach: Apply a minimum amount of epoxy to the mounting surface so that a thin epoxy fillet is observed around the perimeter of the chip once it is placed into position. Cure epoxy per the manufacturer's schedule. For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com Application Support: Phone: 978-250-3343 or apps@hittite.com BIAS CONTROLLERS - CHIP Handling Precautions 10 HMC981 v00.0611 ACTIVE BIAS CONTROLLER BIAS CONTROLLERS - CHIP Application Notes Detailed Description The HMC981 is a fully-integrated Active Bias Controller (ABC) that automatically adjusts the gate voltage of amplifiers operating in the Class-A regime. With an internal feedback the automatic gate voltage control achieves constant quiescent bias through the amplifier under bias, independent of temperature and amplifier threshold variations. The quiescent current is adjusted with a resistor connected externally. The HMC981 employs an integrated control circuitry to achieve safe power-up and power-down sequencing of the targeted amplifier. The HMC981 can provide auto-bias solution virtually any amplifier in the market (both enhancement and depletion type) with a quiescent current of up to 200 mA and a supply voltage of up to 12V. The HMC981 has an integrated negative voltage generator to synthesize negative voltages required to drive depletion mode amplifiers. If an external negative supply is already available or an enhancement mode device is targeted, the negative voltage generator can be disabled. The HMC981 achieves excellent bias stability over supply and temperature variations with low supply voltage down to 4V. The gate control can both sink and source current (0.8 mA) to achieve constant bias current over input power variations applied to the amplifier. The HMC981 also generates a second gate voltage (VG2). VG2 can be adjusted through a resistor divider connected to VDD for amplifiers which require second gate voltage. The HMC981 ensures the protection of the external amplifier during turn on/off by adjusting the sequence of VDRAIN, VGATE and VG2 outputs. HMC981 controls the bias current of the amplifier under bias with the gate control driver. The current passing through the amplifier is continuously sampled and is used to control the VGATE voltage connected to the gate of the amplifier. The HMC981 employs a SW pad to control RDS_ON resistance of the internal switch between VDD and VDRAIN. Refer to the section under the "Supply and Drain Voltage" section for details. The HMC981 has a built-in short circuit protection feature to protect both itself and the amplifier under bias against short circuit conditions at the VDRAIN output. Refer to the section under the "Short Circuit Protection" section for details. Digital Power Supply (VDIG) The HMC981 requires an external low voltage bias rail (3.3V to 5.0V). VDIG powers the internal logic circuitry. VDIG draws an average of 3 mA from a 3.3V. VDIG can accept voltages up to 5.0V. Supply and Drain Voltage (VDD and VDRAIN) The VDD supply to the HMC981 is directly connected to the VDRAIN output through an internal MOSFET switch. This internal MOSFET is controlled through power-up sequencing which ensures that no voltage is applied to drain of the external amplifier until the gate voltage is pulled down to VNEG(ensuring external amplifier is pinched-off). The VDRAIN output of the HMC981 should be connected to the drain (collector) of the amplifier under bias for the active bias control feedback and power-up/down sequencing to work. 11 For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com Application Support: Phone: 978-250-3343 or apps@hittite.com HMC981 v00.0611 ACTIVE BIAS CONTROLLER There will be a voltage drop from VDD to VDRAIN due to finite RDS_ON resistance of the internal switch. To compensate for this voltage drop choose the VDD value as shown in equation (1). (1) where VDRAIN is the supply voltage of the external amplifier and IDRAIN is the desired constant bias current through the external amplifier. Note that RDS_ON resistance of the internal FET switch can be adjusted through SW pad. RDS_ON is typically equal to 5 Ohms when SW is pulled up to VDIG, and is typically equal to 10 Ohms when SW is pulled down to GND. If SW is left floating, it is pulled up to VDIG through an internal weak pull-up. Recommended settings for the SW position are given in Table-1. Not using the HMC981 in the recommended settings will increase the power dissipation of the part and may increase the part-to-part variation. Table 1. Recommended Current Range Configuration Current Range (mA) Condition RDS_ON (Ohm) 20 to 80 SW=GND 10 80 to 200 SW=VDIG 5 Negative Voltage Generator (VNEGOUT) The HMC981 has an internally regulated charge pump block to generate negative voltage (VNEGOUT) required for depletion mode devices. The HMC981 generates -2.5V at the VNEGOUT output in default configuration. It requires two diodes and two capacitors connected externally as shown in the sample application schematics. The HMC981 is designed to reject the ripple on the VNEGOUT by isolating VNEGOUT from the VGATE. The negative voltage is only required for depletion mode devices, and it can be disabled through the VGATEFB and VNEGFB pads. Where an enhancement device is targeted or a negative supply is already available in the system, simply connect the available negative supply to the VNEG pad. See Table-2 for detail on how to set this operation mode. BIAS CONTROLLERS - CHIP VDD = VDRAIN + IDRAIN x RDS_ON Enable/Disable (EN) The active bias control loop is enabled when EN is pulled up to VDIG, and it is disabled when it is pulled down to GND. If EN is left floating HMC981 is enabled through an internal weak pull-up. Note that VNEG operation is independent of EN condition. EN signal controls the operation of only VGATE, VG2 and VDRAIN outputs. When EN pulled down to GND, the HMC981 discharges VDRAIN and VG2 down to GND and it pulls the VGATE down to VNEG. Please see the "Active Bias Control Loop" section for detailed explanation. Active Bias Control Loop The HMC981 regulates the bias current (IDRAIN) of the amplifier under bias through VGATE output connected to the gate of the external amplifier. In this closed loop operation the current passing through the amplifier under bias is sampled and is used to adjust VGATE to achieve constant quiescent bias through the external amplifier. The HMC981 continuously compensates for any supply, temperature, process variations and threshold drifts due to aging. The part-to-part, temperature, and supply variation of the HMC981 is excellent. Thus, by using an accurate sense resistor connected to the ISENSE pad, expensive calibration procedures in high volume production could be avoided. For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com Application Support: Phone: 978-250-3343 or apps@hittite.com 12 HMC981 v00.0611 ACTIVE BIAS CONTROLLER BIAS CONTROLLERS - CHIP The gate control of the HMC981 is designed to both sink and source current in to the gate of the targeted amplifier (at least 0.8 mA). This unique feature is important to achieve nearly constant quiescent bias through the amplifier under varying gate current at different input power values. The bias current passing through the external amplifier can be adjusted with RSENSE, where RSENSE is the R10 connected from ISENSE to GND. Use the relation given in equation (2) to set the desired bias current through the external amplifier. IDRAIN=32/Rsense (A) (2) Self Protection Feature Due to the small resistance of the internal switch FET a large amount of current may flow through the HMC981. HMC981 limits the maximum current to protect itself under such fault conditions, by turnung of VDRAIN and VGATE. The HMC981 will remain in this protection mode until a full power-cycle or enable/disable cycle is applied. VNEG Fault Detection Feature In depletion mode operation VNEG is continuously monitored against short circuit fault to GND. If VNEG rises above a preset value (typically -1V) the system and the external amplifier are disabled by pulling VDRAIN and VG2 to GND and VGATE to VNEG. The system will stay in this stand-by mode until short fault at VNEG is fixed. Power-up and Enable Sequencing To ensure the protection of the external amplifier, the HMC981 provides a power-up sequence for enabling active bias control loop. During start-up VDRAIN and VG2 are kept at GND while VGATE is taken to the most negative supply available (VGATE=VNEG). This ensures that external amplifier is completely pinched-off before VDRAIN is applied. When EN signal is received, VDRAIN is applied and the active bias loop is enabled. After the VDRAIN is applied, VG2 is generated. The final phase of the power-up sequence is completed by increasing the VGATE linearly until the set IDRAIN value is achieved. For power-down and disabling the same sequencing is applied in the reverse order. Daisy-Chain Operation HMC981 produces a trigger out signal (TRIGOUT pad#13) when VDRAIN output is enabled. This trigger signal can be used to enable additional HMC981 chips in a chain of amplifiers. The triggering sequence can be routed in any way, from input to output, or from output to input depending on the use. Figure-1 presents a sample use of three HMC981s in an amplification chain. Please note that, only one of the HMC981 is used to generate the negative voltage and the remaining HMC981 is set to receive external negative voltage (which is provided from the master HMC981). Generating negative voltage from a single HMC981 reduces the number of the components in the system, and decreases the over all current consumption.. Please note that, to ensure proper start-up, the system enable signal should be applied to the chip that has the negative voltage generator. 13 For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com Application Support: Phone: 978-250-3343 or apps@hittite.com HMC981 v00.0611 BIAS CONTROLLERS - CHIP ACTIVE BIAS CONTROLLER Figure 1. Daisy Chain Operation Operation Modes HMC981 can be configured to bias both enhancement and depletion mode external amplifiers. The mode of operation can be selected by setting two pads (VNEGFB, VGATEFB) as tabulated in Table-2. The connection to the VNEGIN should be adjusted accordingly. In order not to bias external amplifier in a wrong region, please make sure that the correct mode of operation is selected before powering up the HMC981. The HMC981 does not allow the internal negative voltage generator to work if an enhancement mode is selected. Therefore, if VNEGFB is left floating while VGATEFB is grounded, HMC981 will stay in standby mode. Please note that the external negative voltage should be between -2.5V to -3.5V for HMC981 to operate. If your application requires negative voltages outside this range please contact Hittite application support. Table 2 - Mode Selection MODE1 (Depletion/Master Mode) MODE2 (Depletion/Slave Mode) --MODE3 (Enhancement Mode) VNEGFB VGATEFB VNEGIN Description FLOAT FLOAT Connected to VNEGOUT Depletion mode transistor. Internal negative voltage generator is active and generates -2.5V. Sample application schematic given shown in Fig.2a. GND FLOAT Connected to External VSS Depletion mode transistor. Internal negative voltage generator is disabled. An external negative voltage less than -2.3V should be connected to VNEGIN. Sample application schematic given shown in Fig.2b. FLOAT GND N/A Not allowed. HMC981 stays in standby. GND GND Connected to GND Enhancement mode transistor. Internal negative voltage generator is disabled. Sample application schematic given shown in Fig.2c. For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com Application Support: Phone: 978-250-3343 or apps@hittite.com 14 HMC981 v00.0611 BIAS CONTROLLERS - CHIP ACTIVE BIAS CONTROLLER Figure 2a. Depletion/Master Mode Amplifier Typical Application Circuit (Mode 1) Figure 2b. Depletion/Slave Mode Amplifier Typical Application Circuit (Mode 2) 15 For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com Application Support: Phone: 978-250-3343 or apps@hittite.com HMC981 v00.0611 Figure 2c. Enhancement Mode Amplifier Typical Application Circuit (Mode 3) Table 3 - List of Bias Settings for Various Hittite Amplifiers Hittite Part Number VDRAIN (V) VDD (V) IDRAIN (mA) RSENSE (kOhm) R2 (kOhm) R1 (kOhm) VG2 (V) LNAs HMC-ALH140 4 4.60 60 0.53 open open - HMC-ALH216 4 4.45 90 0.36 open open - HMC-ALH244 4 4.45 45 0.71 open open HMC-ALH310 [1] 2.5 3.02 [1] 52 0.62 open open - HMC-ALH311[1] 2.5 3.04 [1] 54 0.59 open open - HMC-ALH313 [1] 2.5 3.02 [1] 52 0.62 open open - HMC-ALH382 [1] 2.5 3.14 [1] 64 0.50 open open - 5 5.30 30 1.07 5.60 5 1.5 HMC-ALH435 HMC-ALH444 5 5.55 55 0.58 5.09 5 1.5 HMC-ALH476 4 4.45 90 0.36 open open - HMC490 5 6.00 200 0.16 open open - HMC490LP5 5 6.00 200 0.16 open open - HMC504LC4B 4 4.45 90 0.36 open open - HMC594 6 6.50 100 0.32 open open - HMC594LC3B 6 6.50 100 0.32 open open - HMC609 6 6.85 170 0.19 open open - HMC609LC4 6 6.85 170 0.19 open open - HMC752LC4[1] 3 3.70 [1] 70 0.46 open open - HMC753LP4E 5 5.55 55 0.58 5.09 5 1.5 HMC772LC4 4 4.45 45 0.71 open open - BIAS CONTROLLERS - CHIP ACTIVE BIAS CONTROLLER Linear & Power HMC-ABH209 5 5.80 80 0.40 open open - HMC-ABH264 5 5.60 120 0.27 open open - HMC-AUH317 4 4.80 160 0.20 open open - [1] For applications below 4V supply please contact factory. For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com Application Support: Phone: 978-250-3343 or apps@hittite.com 16 HMC981 v00.0611 ACTIVE BIAS CONTROLLER Table 3 - List of Bias Settings for Various Hittite Amplifiers (Continued) BIAS CONTROLLERS - CHIP Hittite Part Number VDRAIN (V) VDD (V) IDRAIN (mA) RSENSE (kOhm) R2 (kOhm) R1 (kOhm) HMC-AUH318 4 4.80 160 0.20 open open VG2 (V) - HMC-AUH320 4 4.65 130 0.25 open open - HMC442 5 5.43 85 0.38 open open - HMC442LC3B 5 5.42 84 0.38 open open - HMC442LM1 5 5.43 85 0.38 open open - HMC499 5 6.00 200 0.16 open open - HMC499LC4 5 6.00 200 0.16 open open - Wideband (Distributed) HMC-ALH482 4 4.45 45 0.71 open open - HMC-AUH232 5 5.90 180 0.18 4.52 5 1.5 HMC-AUH249 5 6.00 200 0.16 4.38 5 1.5 HMC-AUH312 8 8.60 60 0.53 2.82 5 1.8 HMC460 8 8.60 60 0.53 open open - HMC460LC5 8 8.75 75 0.43 open open - HMC463 5 5.60 60 0.53 open open - HMC463LH250 5 5.60 60 0.53 open open - HMC463LP5 5 5.60 60 0.53 open open - HMC465 8 8.80 160 0.20 2.33 5 1.5 HMC465LP5 8 8.80 160 0.20 2.33 5 1.5 HMC562 8 8.80 80 0.40 open open - HMC633 5 5.90 180 0.18 open open - HMC633LC4 5 5.90 180 0.18 open open - HMC634 5 5.90 180 0.18 open open - HMC634LC4 5 5.90 180 0.18 open open - HMC-930 10 10.88 175 0.18 3.95 5 3.5 HMC870LC5 7 7.83 165 0.19 open open - HMC871LC5 8 8.38 75 0.43 open open - Microwave & Optical Drivers 17 For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com Application Support: Phone: 978-250-3343 or apps@hittite.com HMC981 v00.0611 ACTIVE BIAS CONTROLLER BIAS CONTROLLERS - CHIP Notes: For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com Application Support: Phone: 978-250-3343 or apps@hittite.com 18