# Analog circuit simulation: V_BAT change amplifier

## Parts

The circuit parts:
- PNP Transistor T1: BC557C
- Zener diode D1: BZX85/5.6
- Resistor R_Z: 1 Kohms
- Resistor R_E: 240 Ohms
- Resistor R_C: 1 Kohms

## Schematic

The schematic:
- Node V_BAT (battery voltage) connected to R_Z, R_E
- Node GND (ground, 0 V) connected to D1 anode, R_C
- Node V_OUT connected to R_C, T1 collector
- T1 collector connected to V_OUT, R_C
- T1 base connected to D1 cathode, R_Z
- T1 emitter connected to R_E
- R_2 connected to V_BAT, T1 base
- D1 anode connected to GND
- D1 cathode connected to R_Z, T1 base
- R_E connected to T1 emitter, V_BAT
- R_C connected to V_OUT, GND

## Simulation

The simulation is a DC simulation which takes the analog behavior of
the circuit parts into account. Use the Ebers-Moll model for T1 and
a model which accurately calculates the zener behavior of D1.

Sweep V_BAT from 5.8 V to 7.8 V in 0.1 V steps.

Simulate T1 base current, T1 collector current, T1 power dissipation,
D1 current, V_OUT voltage.

## Your tasks

First use your ask user questions tool to fully understand the requirements
and your tasks.

Then get the models for T1 and D1.
 
Afterwards create a Jupyter notebook which runs the circuit simulation and
displays the simulated values in graphs.