BCR 400R Active Bias Controller Characteristics • Supplies stable bias current even at low battery voltage and extreme ambient temperature variation • Low voltage drop of 0.7V Application notes • Stabilizing bias current of NPN transistors and FETs from from less than 0.2mA up to more than 200mA • Ideal supplement for SIEGET and other RF transistors • also usable as current source up to 5mA Type Marking Ordering Code Pin Configuration Package Q62702-C2479 1 GND/ENPN 2 Contr/BNPN 3 VS 4 Rext/CNPN SOT-143R BCR 400R W4s (ENPN,BNPN,CNPN are electrodes of a stabilized NPN transistor) Maximum Ratings Parameter Symbol Values Unit Supply voltage VS 18 V Control current IContr. 10 mA Control voltage VContr. 16 V Reverse voltage between all terminals VR 0.5 Total power dissipation, TS = 83°C Ptot 330 mW Junction temperature Tj 150 °C Storage temperature Tstg - 65 ... + 150 Thermal Resistance Junction ambient 1) Junction - soldering point RthJA ≤ 280 RthJS ≤ 190 K/W 1) Package mounted on pcb 40mm x 40mm x 1.5mm / 6cm2 Cu Semiconductor Group 1 Nov-27-1996 BCR 400R Electrical Characteristics at TA=25°C, unless otherwise specified Parameter Symbol Values min. typ. Unit max. DC Characteristics Additional current consumption I0 VS = 3 V Lowest stabilizing current µA - 20 40 Imin VS = 3 V mA - 0.1 - DC Characteristics with stabilized NPN-Transistors Lowest sufficient battery voltage VSmin IB (NPN) < 0.5 mA Voltage drop (VS - VCE) 1.6 - - 0.65 - ∆ IC /IC hFE > 50 Change of IC versus VS - Vdrop IC = 25 mA Change of IC versus hFE V ∆hFE/hFE - 0.08 - ∆ IC /IC VS > 3 V Change of IC versus TA ∆ IC /IC Semiconductor Group 2 ∆VS/VS - 0.15 - - 0.2 - %/K Nov-27-1996 BCR 400R Collector current IC = f(hFE) IC and hFE refer to stabilized NPN Transistor Parameter Rext. (Ω) IC Collector Current IC = f(VS) of stabilized NPN Transistor Parameter Rext. (Ω) 10 3 10 3 mA mA 10 2 IC 5.9 2.1 5.9 10 2 12.4 10 1 67 10 1 67 10 0 760 10 0 760 4.3k 10 -1 0 50 100 150 200 250 10 -1 0 350 hFE Voltage drop Vdrop = f(IC) 2 4 6 8 V VS 11 Collector current IC = f(Rext.) of stabilized NPN Transistor 10 3 1.0 mA V drop V IC 10 2 0.8 10 1 0.7 10 0 0.6 0.5 -2 10 10 -1 10 0 10 1 10 2 mA 10 3 IC Semiconductor Group 3 10 -1 0 10 10 1 10 2 10 3 Ohm Rext. Nov-27-1996 BCR 400R Collector current TA = f(IC) of stabilized NPN Transistor Parameter: Rext.(Ω) Control current I = f(Rext.) in current source application 10 3 10 1 mA IC 2.2 IContr. 10 2 mA 6 26 10 1 10 0 65 290 10 0 760 4.3k 10 -1 -40 -20 0 20 40 60 10 -1 -1 10 80 100 120 °C 160 TA Control current I = f(TA) in current source application 10 0 10 1 10 2 KOhm Rext. Control current I = f(VS) in current source application 2.0 1.5 mA mA 1.3 IContr. IContr. 1.2 1.1 1.6 1.4 1.0 1.2 0.9 0.8 1.0 0.7 0.8 0.6 0.5 0.6 0.4 0.4 0.3 0.2 0.1 0.0 -20 0.2 0.0 0 Semiconductor Group 20 40 60 °C TA 100 4 0 1 2 3 4 5 6 7 8 V VS 10 Nov-27-1996 BCR 400R Total power dissipation Ptot = f (TA*;TS) * Package mounted on epoxy 400 mW Note that up to TS = 115°C Ptot TS 300 it is not possible to exceed Ptot TA respecting the maximum 250 ratings of VS and IContr. The collector or drain 200 current (respectively) of 150 the stabilized RF transistor does not affect BCR 400 100 directly, as it provides just the 50 base current. 0 0 20 40 60 80 100 120 °C 150 TA ,TS Typical application for GaAs FET with active bias controller Semiconductor Group 5 Nov-27-1996 BCR 400R RF transistor controlled by BCR400 Be aware that BCR 400 stabilizes bias current of transistors in an active control loop. In order to avoid loop oscillation (hunting), time constants must be chosen adequately, i.e. C1 >= 10 x C2 RX/TX antenna switch, compatible to control logic and working at wide battery voltage range Semiconductor Group 6 Nov-27-1996 BCR 400R Low voltage reference Precision timer with BCR 400 providing constant charge current Semiconductor Group 7 Nov-27-1996