For the following circuit:
http://i1127.photobucket.com/albums/l637/hrstar24/th_circuit1.jpg
I need to find R1 so that Iz minimum is 5 mA under worst case load, power supply, and component tolerance. Vcc varies +- 10%, β for Q1 is typically 100, but has a min of 40 and a max of 300. VBE is .7 V, and for the zener diode rz = 6Ω, it has a 6.8 voltage drop at a test current of 5 mA. I already got Vzo also. I don't really know where to start.
So in worst case load, power, and tolerance, does that just mean Vcc = 10.8 V, β = 40, and IL is 0? Can I just ignore the BJT in this case? Also the next question asks me to find Iz maximum under worst case conditions, whats the difference between Iz min and Iz max?
http://i1127.photobucket.com/albums/l637/hrstar24/th_circuit1.jpg
I need to find R1 so that Iz minimum is 5 mA under worst case load, power supply, and component tolerance. Vcc varies +- 10%, β for Q1 is typically 100, but has a min of 40 and a max of 300. VBE is .7 V, and for the zener diode rz = 6Ω, it has a 6.8 voltage drop at a test current of 5 mA. I already got Vzo also. I don't really know where to start.
So in worst case load, power, and tolerance, does that just mean Vcc = 10.8 V, β = 40, and IL is 0? Can I just ignore the BJT in this case? Also the next question asks me to find Iz maximum under worst case conditions, whats the difference between Iz min and Iz max?