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! colspan="3" style="background:#ffdead; text-align:left" | Resistors (amp)

! colspan="4" style="background:#ffdead; text-align:left" | Resistors (amp)

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| R₁ || 100 || kΩ

| 18 || R₁ || 100 || kΩ

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| R₂ || 10 || kΩ

| 19 || R₂ || 10 || kΩ

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| R₀ || 560 || Ω

| 1 || R₀ || 560 || Ω

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| R₃ || 1000 || Ω

| 2 || R₃ || 1000 || Ω

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| R₄ || 330 || Ω

| 3 || R₄ || 330 || Ω

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| R₅ || 470 || Ω

| 4 || R₅ || 470 || Ω

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| R₆ || 50 || Ω

| 20 || R₆ || 50 || Ω

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| R₇ || 1360 || Ω

| 5 || R₇ || 1360 || Ω

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| R₉ || 1000 || Ω

| 6 || R₉ || 1000 || Ω

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! colspan="3" style="background:#ffdead; text-align:left" | Resistors (sum)

! colspan="4" style="background:#ffdead; text-align:left" | Resistors (sum)

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| R_a || 120 || Ω

| 8 || R_b || 1220 || Ω

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| R_b || 1220 || Ω

| 9 || R_c || 100 || Ω

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| R_c || 100 || Ω

| 10 || R_d || 82 || Ω

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| R_d || 82 || Ω

| 11 || R_e || 3300 || Ω

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| R_e || 3300 || Ω

| 12 || R_f || 680 || Ω

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| R_f || 680 || Ω

| 13 || R_g || 560 || Ω

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| R_g || 560 || Ω

| 14 || R_h || 180 || Ω

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| R_h || 180 || Ω

|    || R_C || 2500 || Ω

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| R_i || 2000 || Ω

| 15 || R_i || 2000 || Ω

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| R_j || 392 || Ω

| 16 || R_j || 392 || Ω

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| R_E || 700 || Ω

| 17 || R_E || 700 || Ω

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! colspan="3" style="background:#ffdead; text-align:left" | Capacitors

! colspan="4" style="background:#ffdead; text-align:left" | Capacitors

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| C₁ || 10 || nF

| 1 || C₁ || 10 || nF

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| C₂ || 10 || nF

| 2 || C₂ || 10 || nF

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| C₃ || 10 || nF

| 3 || C₃ || 10 || nF

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| C₄ || 1 || nF

| 4 || C₄ || 1 || nF

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| C₅ || 10 || nF

| 5 || C₅ || 10 || nF

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| C_a || 1 || nF

| 6 || C_a || 1 || nF

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| C_c || 10 || nF

| 7 || C_c || 10 || nF

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| C_d || 1 || nF

| 8 || C_d || 1 || nF

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| C_h || 10 || nF

| 9 || C_h || 10 || nF

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| C_C || 1 || nF

| 10 || C_C || 1 || nF

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! style="font-weight:bold" | Num. || Label || Polarity

! style="font-weight:bold" | Num. || Label || Polarity

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| 1 || j || NPN

| 1 || j || NPN

| BJT PNP || NXP (Philips) BFT92W

| BJT PNP || NXP (Philips) BFT92W

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| MOSFET  || NXP (Philips) BF1108(R)<ref>The packaging of BF1108R is a mirror image of that in BF1108. The exact unit is picked depending on the needs of layout.</ref>

| MOSFET  || NXP (Philips) BF1108(R)^{[[#Notes|[1]]]}

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! colspan="3" style="background:#ffdead; text-align:left" | Bypass Components

! colspan="3" style="background:#ffdead; text-align:left" | Bypass Components

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! style="font-weight:bold" | Name || Value

! style="font-weight:bold" | Comp. || BJT (X_Bi) || MOSFET (X_G)

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| C_Bi || 10&nbsp;nF

| C || 10&nbsp;nF || 50&nbsp;nF

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| R_Bi || 154&nbsp;&Omega;

| R || 154&nbsp;&Omega; ||  18&nbsp;&Omega;

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| R_G || 18&nbsp;&Omega;

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== Bypass Circuits ==

== Bypass Circuits ==

The passive components used to bypass high frequency noise to clean up DC levels were picked as follows. The 10&nbsp;nF capacitor frequently used in the circuit was deemed a good choice - high enough without raising concerns of introducing much inductance. This was also Photonique's choice for bypass capacitors in their prototype amplifier. The resistance on the bases of relevant transistors should be same or lower than that of the bench prototype (200&nbsp;&Omega;). 154&nbsp;&Omega; is sufficient, leading to a low pass filter with 3&nbsp;dB point of 100&nbsp;kHz. Frequencies below this point are well out of the amplifier's band (see [[SiPM Amplifier Signal Analysis]].

The passive components used to bypass high frequency noise to clean up DC levels were picked as follows. The 10&nbsp;nF capacitor frequently used in the circuit was deemed a good choice - high enough without raising concerns of introducing much inductance. This was also Photonique's choice for bypass capacitors in their prototype amplifier. The resistance on the bases of relevant transistors should be same or lower than that of the bench prototype (200&nbsp;&Omega;). 154&nbsp;&Omega; is sufficient, leading to a low pass filter with 3&nbsp;dB point of 100&nbsp;kHz. Frequencies below this point are well out of the amplifier's band (see [[SiPM Amplifier Signal Analysis]]).

 

 

The bypass circuit for the gate of the MOSFET switch takes more care. Gate resistance forms a voltage divider with resistance on the Source leg. Given the low value of R_d: 82&nbsp;&Omega;, and the MOSFET specification of V_GS&nbsp;=&nbsp;-4 as the maximum pinch-off value, R_G of 18&nbsp;&Omega; is a good choice. The resulting V_GS when the controlling voltage is pulled down ground is -4.1&nbsp;V.

# The packaging of BF1108R is a mirror image of that in BF1108. The exact unit is picked depending on the needs of layout.