BCRW Active Bias Controller Characteristics Supplies stable bias current even at low battery voltage and extreme ambient temperature variation Low voltage drop of.7v Application notes Stabilizing bias current of NPN transistors and FET's from less than. up to more than Ideal supplement for Sieget and other transistors also usable as current source up to 5 EHA788 Pb-free (RoHS compliant) package ) Qualified according AEC Q Type Marking Pin Configuration Package BCRW Ws =GND/E NPN =Contr/B NPN V S =Rext/C NPN SOT (E NPN, B NPN, C NPN are electrodes of a stabilized NPN transistor) Maximum Ratings Parameter Symbol Value Unit Source voltage V S 8 V Control current I Contr. Control voltage V Contr. 6 V Reverse voltage between all terminals V R.5 Total power dissipation, T S = 7 C P tot mw Junction temperature T j 5 C Storage temperature T stg -65... 5 Thermal Resistance Junction - soldering point ) R thjs K/W Pb-containing package may be available upon special request For calculation of RthJA please refer to Application Note Thermal Resistance 7-5-9
BCRW Electrical Characteristics at T A =5 C, unless otherwise specified Parameter Symbol Values Unit min. typ. max. DC Characteristics Additional current consumption I - µa V S = V Lowest stabilizing current V S = V I min -. - DC Characteristics with stabilized NPN-Transistors Lowest sufficient battery voltage V Smin -.6 - V I B (NPN) <.5 Voltage drop (V S - V CE ) I C = 5 V drop -.65 - Change of I C versus h FE h FE = 5 Change of I C versus V S V S = V I C /I C -.8 - h FE / h FE I C /I C -.5 - V S /V S Change of I C versus T A I C /I C -. - %/K 7-5-9
BCRW Collector current I C = f (h FE ) I C and h FE refer to stabilized NPN Transistor Parameter R ext. (Ω) Collector Current I C = f (V S ) of stabilized NPN Transistor Parameter R ext. (Ω). 5.9 5.9. IC IC 67 67 76 76.k - 5 5 5-5 h FE Voltage drop V drop = f (I C ) - 6 8 V V S Collector current I C = f (R ext. ) of stabilized NPN Transistor V.7.6 Vdrop.5. IC....9.8.7.6.5 - - - Ohm I C R ext. 7-5-9
BCRW Collector current T A = f (I C ) of stabilized NPN Transistor Parameter: R ext. (Ω) Control current I = f (R ext. ) in current source application. 6 IC 6 IContr. 65 9 76.k - - - 6 8 C 6 T A Control current I = f (T A ) in current source application - - KOhm R ext. Control current I = f (V S ) in current source application.5...8 IContr...9.8 IContr..6...7.6.5.8..6..... - 6 8 C 6 8 V T A V S 7-5-9
BCRW Total power dissipation P tot = f (T S ) Ptot mw 5 5 Note that up to T S =5 C it is not possible to exceed P tot respecting the maximum ratings of V S and I Contr. The collector or drain current (respectively) of the stabilized RF transistor does not affect BCR directly, as it provides just the base current. 5 6 8 C 5 T S Typical application for GaAs FET with active bias controller RF IN RF OUT k Ω BCR pf R ext k Ω nf - V G + V S EHA79 5 7-5-9
BCRW RF transistor controlled by BCR BCR +V S R ext. V drop Ι C Be aware that BCR stabilized bias current of transistors in an active control loop C C In order to avoid loop ascillation (hunting), time constants must be chosen adequately, i.e. C >= x C RF IN Ι contr. RF OUT RF-Transistor EHA77 RX/TX antenna switch, compatible to control logic and working at wide battery voltage range TX Antenna λ / RX RX TX BCR R ext = Ω - Ω + V S >.7 V EHA78 6 7-5-9
BCRW Low voltage reference BCR Red LED V REF + V S EHA79 Precision timer with BCR providing constant charge current +V S BCR R ext 7 8 6 5 Timer IC (555) EHA79 7 7-5-9
Package SOT BCRW Package Outline ±... MAX...9 ±. A. +. -.5 x. M.5 +..6 -.5. ±.. MIN.. M Foot Print.6 Marking Layout (Example) 5, June Date code (YM) BGA Type code Standard Packing Reel ø8 mm =. Pieces/Reel Reel ø mm =. Pieces/Reel.. 8.6.8 A.5 +. -.5.5 ±..5.9 Manufacturer Pin Pin.5. 8 7-5-9
BCRW Published by Infineon Technologies AG 876 München, Germany Infineon Technologies AG 7. All Rights Reserved. Attention please! The information given in this data sheet shall in no event be regarded as a guarantee of conditions or characteristics ( Beschaffenheitsgarantie ). With respect to any examples or hints given herein, any typical values stated herein and/or any information regarding the application of the device, Infineon Technologies hereby disclaims any and all warranties and liabilities of any kind, including without limitation warranties of non-infringement of intellectual property rights of any third party. Information For further information on technology, delivery terms and conditions and prices please contact your nearest Infineon Technologies Office (www.infineon.com). Warnings Due to technical requirements components may contain dangerous substances. For information on the types in question please contact your nearest Infineon Technologies Office. Infineon Technologies Components may only be used in life-support devices or systems with the express written approval of Infineon Technologies, if a failure of such components can reasonably be expected to cause the failure of that life-support device or system, or to affect the safety or effectiveness of that device or system. Life support devices or systems are intended to be implanted in the human body, or to support and/or maintain and sustain and/or protect human life. If they fail, it is reasonable to assume that the health of the user or other persons may be endangered. 9 7-5-9