I am implementing the circuit shown in Figure 15 of the Application Note at
http://focus.ti.com/lit/an/sbea001/sbea001.pdf.
In my application, I have a 1Ohm TEC that will draw at most 3A (at 3V). I am trying to determine the amount of power dissipated in each of the two transistors for a given scenario (i.e., Q1 and Q3 on or Q2 and Q4 on). I believe that I can just put a 1Ohm resistor in for the load (where it says TEC in the circuit) and ignore the 0.02Ohm resistor (for this rough order of magnitude calculation). However, I am having a difficult time calculating Vce for the two transistors (abstracted -- I can add the actual characteristics of the transistors later).
My ultimate input signal can vary between 0 and 5V, so I believe that my Vb (referred to ground) can also vary between 0 and 5V. However, I don't know how to get Ve of Q1.
Any advice would be appreciated.
http://focus.ti.com/lit/an/sbea001/sbea001.pdf.
In my application, I have a 1Ohm TEC that will draw at most 3A (at 3V). I am trying to determine the amount of power dissipated in each of the two transistors for a given scenario (i.e., Q1 and Q3 on or Q2 and Q4 on). I believe that I can just put a 1Ohm resistor in for the load (where it says TEC in the circuit) and ignore the 0.02Ohm resistor (for this rough order of magnitude calculation). However, I am having a difficult time calculating Vce for the two transistors (abstracted -- I can add the actual characteristics of the transistors later).
My ultimate input signal can vary between 0 and 5V, so I believe that my Vb (referred to ground) can also vary between 0 and 5V. However, I don't know how to get Ve of Q1.
Any advice would be appreciated.