HMC981 v00.0611 ACTIVE BIAS CONTROLLERPad Descriptions Pad Number Function Description Interface Schematic IP 1, 5, 8, 10, H 13, 15, 20, These pads and the die bottom must be connected to a GND 23, 25, 26, high quality RF/DC ground. Die Bottom Enable pad. System is enabled when Ven is HIGH (VDIG). 2 EN S - C If left floating, Ven defaults to HIGH (enabled). R Internal switch resistance control pad. If left floating, VSW 3 SW defaults to HIGH. LLE Disables short circuit lock down when pulled to ground. 12 DISBLSC O Leave it floating to enable short circuit lock down. R T Control voltage of the VG2. Use a resistor divider between N 4 VG2CONT VDD and GND to set the voltage. VG2 is typically 1.3V O lower than the VG2CONT S C IA 19 VG2 Second gate control. B Bias supply pan. Connect supply voltage 6-7, 29-30 VDD, VDIG to this pad with appropriate filtering. 1.5V reference voltage. 0.1uF or greater capacitor to GND 9 VREF is needed for noise filtering. To adjust the bias current of the external amplifier connect a resistor (Rsense) from ISENSE pad to GND. Use Eqn.2 11 ISENSE to determine the required Rsense value. 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 7 license is granted by implication or otherwise under any patent or patent rights of Analog Devices. www.analog.com 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