Download ECE1250F14_HWC2

1250
F 14
1.
Homework Circuit System Design Cards 2
According to datasheets, we have the following voltage levels for a LM324 output
when used as a comparator and for a 74HC00 NAND gate input:
LM324
Characteristic
Symbol Min
VOH
3.3
Typ
3.5
V
Output Voltage-High Limit
(VCC = 30 V)
VOH
26
28
V
Output Voltage-Low Limit
(VCC = 5 V)
VOL
5.0
20
mV
Output Voltage-High Limit
(VCC = 5 V)
Max
Unit
74HC00
Characteristic
High-level input voltage
(VCC = 4.5 V)
Symbol Min
VIH
3.15
Typ
Max
Unit
V
Absolute Min VIN
VIN
Low-level input voltage
(VCC = 4.5 V)
VIL
1.35
V
Absolute Max VIN
VIN
5
V
–0.5
V
LM324 datasheet: http://www.digikey.com/productsearch/en?vendor=0&keywords=lm324ngos
74HC00 datasheet: http://www.digikey.com/productsearch/en?x=0&y=0&lang=en&site=us&keywords=tc74hc00
Use the equations on the "Op-amp Level-Shifter" card (see below) to find resistor
values to shift from vTh<Hi to vThHi and from vTh<Hi to vThHi. Assume RTh< = 0 Ω.
Use resistors that are as large as possible without exceeding 1 MΩ.
ANS:
1. TBA