Analog
BOOT
CAMP
OP
AMP ESSENTIALS - LEVEL 1
1. NON-INVERTING AMPLIFIER. A sensor signal (Vs=1 Vmax) needs to increased to drive an ADC input (Vo = 4 Vmax). What is the Kv needed?
a) 2 b) 4 c) 1/2 d) 1/4
2. What value of R2 is needed (R1=10k) to achieve this gain?
a) 10k b) 20k c) 30k d) 40k
3. INVERTING AMPLIFIER. Amplify a temperature sensor signal (1 Vmax) to the level required for a temp controller input of (-10 Vmax). What is the Kv needed?
a) -1 b) -2 c) -5 d) -10
4. What value of R2 is needed (R1=10k) to achieve this inverting gain?
a) 100k b) 50k c) 20k d) 10k
5. DIFFERENTIAL AMPLIFIER. A sensor signal (VIN=0.1V and VCM=5V) needs to be amplified to 1V. For R1=R3=1k, what value of R2=R4 is needed to get this output?
a) 90k b) 100k c) 9k d) 10k
6. SUMMING AMPLIFIER You’ve been asked to process a signal V1 = +/-1 Vpk (1V to -1V) that needs to be amplified and shifted for a 0 to 4V ADC input. There’s also a reference available V2=-10V. (V3 and R3 are not needed.) For RF=100k, what value of R1 and R2 is needed to get this desired output?
a) R1=500k,R2=50k b) R1=50k, R2=500k c) R1=100k, R2=20k d) R1=5k, R2=50k
7. I-TO-V CONVERTER There's a photodiode that produces an output of IS=10uA. You need to convert this current into a voltage Vo=-1V. What value of RF brings the output to -1V?
a) RF=10M b) RF=1M c) RF=100k d) RF=10k
8. I-TO-V WITH OFFSET. Today’s design challenge asks you to transform a current DAC output for an audio system (0 mA to -2mA) into the required voltage output (-2V to +2V). There’s also a reference available V1=4V. Choose R1 and RF needed to meet the design goal.
a) R1=1k,RF=1k b) R1=4k, RF=2k c) R1=1k, RF=2k d) R1=2k, RF=4k?
9. SINGLE-POLE LOW-PASS FILTER. You need to reduce a 25 kHz noise on your 1 kHz signal. Design a single-pole low-pass filter with the cutoff frequency at fc=5kHz. Choose CP1=10nF and determine RP1.
a) RP1=3.18k b) RP1=1.59k c) RP1=15.9k d) RP1=31.8k
10. DOUBLE-POLE (SALLEN-KEY) LOW-PASS FILTER. You need to reduce a 25 kHz noise signal on your 1 kHz signal. Design a double-pole low-pass filter with the cutoff frequency at fc=5kHz. Choose CP2=10nFand find RP1=RP2 and CP1.
a) RP1=22.5k,CP1=20nF b) RP1=11.3k,CP1=5nF c) RP1=1.13k,CP1=10nF d) RP1=2.25k,CP1=20nF
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