Reference · Appendix A
Quick Reference Tables
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A.1 Solder and temperature reference
| Item | Value |
|---|---|
| Sn63/Pb37 melting point | 183 °C (eutectic) |
| SAC305 melting range | ≈217–220 °C |
| Sn42/Bi58 melting point | 138 °C |
| Iron, leaded, small pads (typical) | 300–340 °C |
| Iron, lead-free (typical) | 340–380 °C |
| Hot air, small passives (typical) | 300–350 °C, low airflow |
| Board preheat (typical) | 100–150 °C |
| Phone screen adhesive softening (surface) | about 60–80 °C |
A.2 Lithium-ion cell voltages
| State | Per cell |
|---|---|
| Nominal | 3.6–3.85 V |
| Full charge (standard) | 4.20 V |
| Full charge (high-voltage cells) | about 4.35–4.45 V |
| Discharge cut-off (typical) | about 3.0 V |
| Laptop pack | Nominal | Full (4.2 V cells) |
|---|---|---|
| 2S | 7.2–7.7 V | 8.4 V |
| 3S | 10.8–11.55 V | 12.6 V |
| 4S | 14.4–15.4 V | 16.8 V |
A.3 ATX PSU rails
| Colour | Rail | Range (±5% unless stated) |
|---|---|---|
| Yellow | +12 V | 11.40–12.60 V |
| Red | +5 V | 4.75–5.25 V |
| Orange | +3.3 V | 3.14–3.47 V |
| Purple | +5 VSB | 4.75–5.25 V |
| Blue | −12 V | ±10% |
| Green | PS_ON# | Ground to start |
| Grey | PWR_OK | High when outputs stable |
A.4 USB power
| Standard | Voltage | Max power |
|---|---|---|
| USB 2.0 port | 5 V | 2.5 W (500 mA) |
| USB 3.x port | 5 V | 4.5 W (900 mA) |
| USB BC 1.2 charging | 5 V | 7.5 W (1.5 A) |
| USB-C current (no PD) | 5 V | 7.5 W (1.5 A) or 15 W (3 A) |
| USB PD SPR | 5 / 9 / 15 / 20 V | up to 100 W |
| USB PD EPR | 28 / 36 / 48 V | up to 240 W |
A.5 SMD resistor codes
| Code | Value |
|---|---|
| 100 | 10 Ω |
| 101 | 100 Ω |
| 102 / 1001 | 1 kΩ |
| 472 | 4.7 kΩ |
| 103 / 1002 | 10 kΩ |
| 104 | 100 kΩ |
| 105 | 1 MΩ |
| 4R7 | 4.7 Ω |
| R100 | 0.1 Ω |
| R010 | 0.01 Ω |
| 000 | 0 Ω jumper |
EIA-96 (1% resistors, 2 digits + letter): the two digits give a value from the E96 table (01 = 100, 02 = 102, … 96 = 976) and the letter is the multiplier: Z = ×0.001, Y/R = ×0.01, X/S = ×0.1, A = ×1, B/H = ×10, C = ×100, D = ×1,000, E = ×10,000, F = ×100,000. Example: 01C = 100 × 100 = 10 kΩ. Use a full E96 lookup table for other codes.
A.6 Ceramic capacitor values
| Value | Equivalent |
|---|---|
| 100 nF | 0.1 µF (common decoupling) |
| 1 µF | 1,000 nF |
| 10 µF, 22 µF, 47 µF | Common bulk filtering on rails |
| 22 pF | Common crystal load capacitor |
A.7 Common button combinations
| Device | Function | Combination |
|---|---|---|
| iPhone 8 and later | Force restart | Vol Up (press, release), Vol Down (press, release), hold Side until Apple logo |
| iPhone 8 and later | Recovery | As above but keep holding Side until recovery screen, connected to computer |
| iPhone 7 | Force restart / Recovery | Hold Side + Vol Down |
| iPhone 6s and earlier | Force restart / Recovery | Hold Home + Side/Top |
| Samsung (current) | Force restart | Hold Side + Vol Down about 7–10 s |
| Samsung (current) | Download mode | Power off; hold Vol Up + Vol Down and connect USB cable |
| Many Android | Recovery | Power off; Power + Vol Up (varies) |
| Pixel | Bootloader/fastboot | Power off; Power + Vol Down |
| Intel Mac | macOS Recovery | Hold Cmd + R at startup |
| Apple-silicon Mac | Startup options / Recovery | Hold the power button until “Loading startup options” |
| Windows | WinRE | Shift + Restart, or 3 interrupted boots |
Always check the manufacturer’s current support page for the specific model; combinations change between generations.
A.8 Screwdriver bits
| Bit | Typical use |
|---|---|
| Pentalobe P2 (0.8 mm) | iPhone bottom screws |
| Pentalobe P5 (1.2 mm) | MacBook bottom case (several models) |
| Tri-point Y000 | iPhone internal brackets (iPhone 7 and later) |
| Phillips PH000 / PH00 | Phones, laptop internals |
| Phillips PH0 / PH1 | Laptop bottom covers, desktops |
| Torx T3–T6 | MacBook internals, many laptops, Samsung internals |
| Torx T8–T10 | Game consoles, some laptops, HDDs |