# minikv bill of materials, rev 2

Components marked "crit" are critical and should be populated with exactly the
recommended manufacturer part number in the table. Reasons for these critical
parts are explained below so they may be substituted if absolutely necessary,
but do this with care.

Components with no part number are common parts expected to be provided by the
builder according to the description.

Parts with reference numbers greater than 10 are on the secondary winding board.

| Part   | Description                                     | Crit | Manufacturer | Manufacturer's part number |
|:-------|:------------------------------------------------|:----:|:-------------|:---------------------------|
| C1     | Capacitor, MLCC, 10µF, 25V, 0805                |      |              |                            |
| C2, C4 | Capacitor, MLCC, 100nF, 25V, 0603               |      |              |                            |
| C3     | Capacitor, MLCC, 2.2nF, 25V, 0603               |      |              |                            |
| C5     | Capacitor, MLCC, 15nF, 100V, C0G, 1206          |      |              |                            |
| C11-12 | Capacitor, MLCC, 6.8nF, 2kV, X7R, 1210          |      | KEMET        | C1210C682MGRAC7800         |
| C13    | Capacitor, MLCC, 27nF, 2kV, X7R, 2220           |      | KYOCERA AVX  | 2220GC273KAZ1A             |
| D11-12 | Diode, 2kV, 500mA, trr ≤ 500ns, SMA             |      | Micro Commercial Co | FM2000GP            |
| J1     | Header, shrouded, 1x12, 2.0mm                   |      | JST          | B12B-PH-K-S(LF)(SN)        |
| L1     | Inductor, 220µH, 1A, 10x10mm                    | Yes  | Bourns       | SRN1060-221M               |
| L11    | Inductor, 1mH, 15mA, 1007                       |      | Taiyo Yuden  | LB2518T102K                |
| Q1, Q2 | Transistor, NPN, 100V, 1A, low Vcesat, SOT-23   | Yes  | Nexperia     | PBSS8110T,215              |
| R1     | Resistor, 10M, 1%, high voltage, 2010           | Yes  | Bourns       | CHV2010-FX-1005ELF         |
| R2     | Resistor, 330k, 1%, 0603                        |      |              |                            |
| R3     | Resistor, 7k5, 1%, 0603                         |      |              |                            |
| R4     | Resistor, 1M, 1%, 0603                          |      |              |                            |
| R5     | Resistor, 68k, 1%, 0603                         |      |              |                            |
| R6, R11| Resistor, 430, 5%, 0.4W, 0805                   |      | Rohm Semi    | ESR10EZPJ431               |
| U1     | Step-down regulator, 30V, 1.2A, 1.4MHz          | Yes  | RYCHIP       | RY8310
| n/a    | Planar E-core, 22x16mm                          | Yes  | Ferroxcube   | E22/6/16/R-3F36            |
| n/a    | Planar E-core plate, 22x16mm                    | Yes  | Ferroxcube   | PLT22/16/2.5/S-3F36        |
| n/a    | Planar E-core transformer clamp                 | Yes  | Ferroxcube   | CLM-E22/PLT22              |

L1: "Critical" due to proprietary footprint. If you can find one that fits, go
for it. I<sub>rms</sub> and I<sub>sat</sub> should both be 1A or higher.

Q1, Q2: These are low-Vce<sub>sat</sub> transistors meant for use in SMPS
circuits. Using "normal" transistors in place of these may cause overheating
and failure. If needed, Zetex and Nexperia have many alternatives.

R1: This resistor must permit continuous operation at up to 2000V and have a
power rating of at least 250mW. Don't just filter for "high voltage" at
Digi-Key, check for "maximum working voltage" in the datasheet.

U1: This circuit can be made to run on any similar synchronous buck converter,
but the pinout needs to match, and the loop compensation will likely need to be
adjusted.

Transformer core components: These are completely critical, the board is
designed around them. If you can find a piece of similar ferrite material that
will fit in the same place, it might work, but don't count on it. If this piece
is obsoleted we'll have to make a new minikv.