Block Diagram Nikon onfocal microscope PMT Signal Electronic

Block Diagram Nikon (on-focal ) microscope PMT Signal Electronic Box NI： PC Including： DAQ card • Voltage Follower (model #： PCI-6010) Lab. VIEW software • Low-pass Filter • Voltage Difference Amplifier & Lab. VIEW

Operational Amplifier：OP 27 • • Low noise, low drift, low offset Supply voltage ( )：± 12 V (old design) / ± 15 V (new design)

Voltage Follower Change the output impedance while the output voltage equals to the input one. Vsig Vout

Butterworth Low-pass Filter • Synthesize a fourth-order Butterworth low-pass filter by cascading two second-order low-pass section. • Cut off Frequency: f 0 10 k Vsig 2 k 1μ 80 Hz 10 k 12. 35 k 2 k 1μ 2 k 1. 52 k 2 k Vout 1μ 1μ • Ref：J. Millman, “microelectronics：digital and analog circuits & systems” pp. 582 -586 (1979)

Voltage Difference Amplifier • Amplifying the difference between two inputs by a gain factor. • Here Vref is adjustable offset voltage • Note that this circuit applies to negative signal input (old design) Rf R Vsig +Vcc Vout R Vref Rf -Vcc Vout = (Vref - Vsig)*

Voltage Difference Amplifier • Amplifying the difference between two inputs by a gain factor. • Here Vref is adjustable offset voltage • Note that this circuits applies to positive signal input (new design) Rf +Vcc Vref -Vcc Vsig R Vout R Rf Vout = (Vsig - Vref)*

Electronic Circuit Layout (old design) 1. 52 K (502) 12. 35 K (503) 10 K 1000 K 2 K 2 K Signal Input (from detector) Signal ＜ 200 m. V 2 K 1μ 100 K 2 K +Vcc 1μ 1μ Signal Output 100 K 1μ 1000 K (503) -Vcc ≦ 5 V

Electronic Circuit Layout (new design) 1. 52 K (502) 12. 35 K (503) 10 K 1000 K 2 K 2 K 2 K 100 K 2 K Signal Output 100 K Signal Input (from detector) Signal ＜ 200 m. V 1μ 1μ ≦ 5 V To panel potential meter 1000 K

Voltage Meter Driver • Non-inverting Amplifier • To drive the voltage meter ( Reason：to match the meter scale ) • Vout = Vin * ( ) Variable Resistance (50 K) R 1 R 2 Vsig = Vsig Output

Calibrate the Voltage Meter Scale • PMT, Monitor and the Voltage Meter should possess linear relationships • Adjust the gain (ratio of R 1 / R 2) of the non-inverting amplifier with different PMT values • PMT Voltage Range： 0~1000 V Monitor Signal Range： 0~4 V Voltage Meter Reading： 0~10 V • For example： PMT Voltage Monitor Signal Voltage Meter Reading 250 V 1 V 2. 5 V 500 V 2 V 5. 0 V 750 V 3 V 7. 5 V 1000 V 4 V 10. 0 V

Power Line Wiring in the Electronic Box (old design) L：red line N：blue line G：green line G 1 N 2 L switch 3 L N G -V +V ± 12 V com +5 V L N G -V +V +15 V

Power Line Wiring in the Electronic Box (new design) L：red line N：blue line G：green line G 1 N 2 switch 3 L N G -V +V ± 15 V com +5 V L

Electronic and Panel Wiring (old design) To Electronic Circuit V+ V- +5 V Vcom+12 V -12 V (not used) +15 V Power Supply Connect to the input of the voltage meter driver ± 12 V Power Supply To Electronic Circuit Connect to the output of the voltage meter driver - +15 V Output (To PMT) PMT Voltage Monitor PMT Signal Input Signal Offset Signal Output (To DAQ) Voltage meter +

Electronic and Panel Wiring (new design) To Electronic Circuit +5 V Vcom +15 V -15 V (not used) ± 15 V Power Supply Connect to the input of the voltage meter driver To Electronic Circuit Connect to the output of the voltage meter driver - +15 V Output (To PMT) PMT Voltage Monitor PMT Signal Input Signal Offset Signal Output (To DAQ) + Voltage meter

Electronic Testing • multi-meter ： check the circuit before connecting to the power supply. • function generator & oscilloscope ： check whether the output of each component satisfies our expectation： a. Each OP Amp should function properly！(make sure the pins have right voltage. ) b. Voltage Follower：should be exactly the same with the input. c. Low-pass Filter：should filter out the signals with frequency higher than 80 hz. d. Voltage difference amplifier：should amplify our signals with the designed gain factor.

Circuit Layout 1 2 3 4 • • • • • • • • 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 IN Voltage Meter OUT 1 1 1 OFFSET 1 1 ：To V+ ：To Vcom (ground) ：To the panel ：two points connected ：wired

Testing the Frequency Response • With fixed amplitude sinusoidal wave signals, we can test how the electronic circuit box low-pass filter responds to the sinusoidal wave frequencies. Function Generator Freq. Oscilloscope OUTPUT Electronic Circuit Box Input Signal Output Signal Ch. 1 Ch. 2

Experimental Frequency Response • Input : 100 m. V, sinusoidal waves -3 d. B 75

Part List in the Electronic Box Item Quantity OP 27 (with 8 -pin socket) 5 Capacitor (1μF) 4 Resistor (2 kΩ) 4 Resistor (10 kΩ) 2 Resistor (1000 kΩ) 2 Adjustable resistance (5 kΩ) 1 Adjustable resistance (50 kΩ) 2 Ten turns potential meter 1 BNC 4 110 V socket 1 110 V switch with indicator 1 10 V DC voltage meter 1 Power supply (± 15 V) 1