Datasheet HMC981 (Analog Devices) - 8
| Manufacturer | Analog Devices |
| Description | ACTIVE BIAS CONTROLLER |
| Pages / Page | 18 / 8 — HMC981. ACTIVE BIAS CONTROLLER. Pad Descriptions |
| File Format / Size | PDF / 886 Kb |
| Document Language | English |
HMC981. ACTIVE BIAS CONTROLLER. Pad Descriptions
Model Line for this Datasheet
Text Version of Document
HMC981
v00.0611
ACTIVE BIAS CONTROLLER Pad Descriptions
(Continued) Pad Number Function Description Interface Schematic IP H Trigger out signal. Generates a HIGH (3.5V) signal when the active bias system stabilizes. This signal can be 14 TRGOUT used to trigger next device (ENABLE) if more than one HMC981 is used in a daisy chain. S - C R LLE Drain voltage. Should be connected to the supply terminal of the external amplifier. A minimum 100 nF O 16, 17 VDRAIN capacitor has to be placed close to the external amplifier to R improve load regulation. T N O S C Gate Control pad for external amplifier. Connect to the gate (base) of the external amplifier. In order to guarantee IA 18 VGATE stability,a 10μF capacitor should be connected between the gate (base) terminal of the external amplifier and GND B as close to the amplifier as possible. Negative input to the chip. Should be supplied with CPOUT when negative voltage generator is enabled, or connect to 21 VNEG external VSS when negative voltage generator is enabled. For detailed usage please refer to the “Negative Voltage Generator” section. Feedback (Control) pad for Negative Voltage Generator Charge Pump. Float to activate the negative voltage 22 VNEGFB generator / Sort to GND to disable the negative voltage generator. Control pad for VGATEFB. Float VGATEFB when a depletion mode transistor is biased. Selects the mode of 24 VGATEFB operation along with VNEGFB pad. For detailed usage please refer to the Table 2. Negative voltage generator charge pump output. Negative voltage generator needs a flying capacitor, a reservoir 27, 28 CPOUT capacitor and two diodes to operate. Please refer to the application schematic for more info. Inf F or o m r p atio r n ifc ur e n , d ishe e d lbiv y e A r n y a alog n D d t evic o p es is la beclie o eved rd to ebre sa: H ccur iattti e tae M nd re ilicarbloew . H a o ve C wever, o n rp o For price, delivery, and to place orders: Analog Devices, Inc., responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other oration, 2 Elizabeth Drive, Chelmsford, MA 01824 One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106 Phone: 978-250-3343 Fax: 978-250-3373 O rights of third parties that may result from its use. Specifications subject to change without notice. No P rd ho e ne r O : 7 n 81- -3li 2n 9 e a -47 t w 0 w 0 • O w rd .h e it r o tniltie n .c e ao t m license is granted by implication or otherwise under any patent or patent rights of Analog Devices. www.analog.com
8
Application Support: Pho Trademarks and registered trademarks are the property of their respective owners. ne: 978-250-33 A 4 p 3 o plica r a tio p n S p u s p @ po h rt itt : P ite ho . n c e o : 1m -800-ANALOG-D
v00.0611
ACTIVE BIAS CONTROLLER Pad Descriptions
(Continued) Pad Number Function Description Interface Schematic IP H Trigger out signal. Generates a HIGH (3.5V) signal when the active bias system stabilizes. This signal can be 14 TRGOUT used to trigger next device (ENABLE) if more than one HMC981 is used in a daisy chain. S - C R LLE Drain voltage. Should be connected to the supply terminal of the external amplifier. A minimum 100 nF O 16, 17 VDRAIN capacitor has to be placed close to the external amplifier to R improve load regulation. T N O S C Gate Control pad for external amplifier. Connect to the gate (base) of the external amplifier. In order to guarantee IA 18 VGATE stability,a 10μF capacitor should be connected between the gate (base) terminal of the external amplifier and GND B as close to the amplifier as possible. Negative input to the chip. Should be supplied with CPOUT when negative voltage generator is enabled, or connect to 21 VNEG external VSS when negative voltage generator is enabled. For detailed usage please refer to the “Negative Voltage Generator” section. Feedback (Control) pad for Negative Voltage Generator Charge Pump. Float to activate the negative voltage 22 VNEGFB generator / Sort to GND to disable the negative voltage generator. Control pad for VGATEFB. Float VGATEFB when a depletion mode transistor is biased. Selects the mode of 24 VGATEFB operation along with VNEGFB pad. For detailed usage please refer to the Table 2. Negative voltage generator charge pump output. Negative voltage generator needs a flying capacitor, a reservoir 27, 28 CPOUT capacitor and two diodes to operate. Please refer to the application schematic for more info. Inf F or o m r p atio r n ifc ur e n , d ishe e d lbiv y e A r n y a alog n D d t evic o p es is la beclie o eved rd to ebre sa: H ccur iattti e tae M nd re ilicarbloew . H a o ve C wever, o n rp o For price, delivery, and to place orders: Analog Devices, Inc., responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other oration, 2 Elizabeth Drive, Chelmsford, MA 01824 One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106 Phone: 978-250-3343 Fax: 978-250-3373 O rights of third parties that may result from its use. Specifications subject to change without notice. No P rd ho e ne r O : 7 n 81- -3li 2n 9 e a -47 t w 0 w 0 • O w rd .h e it r o tniltie n .c e ao t m license is granted by implication or otherwise under any patent or patent rights of Analog Devices. www.analog.com
8
Application Support: Pho Trademarks and registered trademarks are the property of their respective owners. ne: 978-250-33 A 4 p 3 o plica r a tio p n S p u s p @ po h rt itt : P ite ho . n c e o : 1m -800-ANALOG-D
