Holooly Plus Logo
Holooly Plus Logo

Question 23.4: Simulate the operation of the reference in Fig. 23.22 where ......

Simulate the operation of the reference in Fig. 23.22 where the voltage across the diode is used as a reference voltage. Use a nominal reference current of 1 μA.

23.22
Step-by-Step
The 'Blue Check Mark' means that this solution was answered by an expert.
Learn more on how do we answer questions.
Report Answer

Using Eq. (23.23), we can set R to 700k. The simulation results are seen in Fig. 23.23. The reference voltage change is essentially set by the decrease in the diode voltage with increasing temperature, that is, -1.6 mV/C. At the risk of stating the obvious, this isn’t a very good voltage reference.

R=\frac{n V_{T}}{I}\ln\frac{I}{I_{S}}          (23.23)

23.23

Related Answered Questions

Question: 23.2

Resimulate the BMR in Fig. 20.18 using a cascode current mirror for the PMOS devices as seen in Fig. 23.9. ...

Verified Answer:

Using the cascode current mirror, we expect the cu...
Question: 23.3

Using the topology seen in Fig. 20.22, design a voltage reference with, ideally, zero temperature coefficient. Simulate the design to determine the reference’s sensitivity to changes in temperature and VDD. Comment on the repeatability of the VREF (with process variations from one process run to ...

Verified Answer:

We begin by writing the long-channel equation, Eq....
Question: 23.1

Estimate the temperature performance of the resistor-MOSFET voltage references seen in Fig. 23.3. Assume that the temperature coefficient of the resistor is 2,000 ppm/C, the long-channel process is used where KPn =120 μA/V², and the nominal VDD is 5 V. Use simulations to verify the answers. Also ...

Verified Answer:

For the reference made using the IMEG resistor, Fi...
Question: 23.5

Design a nominally 2.500 V voltage reference (at room temperature of 27 °C or 300 °K) PTAT voltage reference. Use the topology seen in Fig. 23.25 with a bias current of 1 μA. Simulate the operation of the design. ...

Verified Answer:

Let's set K (the number of diodes connected in par...