C1812C124J1GACTU

KEMET C1812C124J1GACTU: MLCC 0.12 uF +/-5 %, 100 V, C0G/NP0, 1812 (4532 metric). A commercial grade, class I multilayer ceramic chip capacitor from KEMET's C0G series (KEMET is part of the YAGEO Group). C0G holds its capacitance against DC voltage, temperature and time, which makes it the choice for timing, tuning, filters, snubbers and other circuits where the value must not move.

Why C0G: stable with voltage, temperature and time

The figures below are KEMET's, from the datasheet on this page:

• Voltage. "No capacitance change with respect to applied rated DC voltage" (p.2; the overview on p.1 says C0G "exhibits no change in capacitance with respect to time and voltage"). At 100 V this part is still 0.12 uF.
• Temperature. Capacitance change is limited to +/-30 ppm/C from -55 to +125 C, referenced to +25 C (p.1, p.4). Worked out from that limit: at most +/-0.3 % at +125 C and +/-0.24 % at -55 C.
• Time. Aging rate 0 % per decade hour (p.4), "no capacitance decay with time" (p.2).
• No piezoelectric noise, low ESR and ESL and high ripple current capability are listed as benefits (p.1).

By contrast, a class II X7R capacitor is allowed +/-15 % over -55 to +125 C (the EIA X7R definition), loses part of its capacitance under DC bias, and ages over time; at a 100 V rating that bias loss can be large. That is the reason to choose this C0G part over an X7R of the same value where the capacitance has to stay put: the cost is size, since 0.12 uF at 100 V needs an 1812 case in C0G.

Key specifications

Page numbers refer to KEMET C1003_C0G, 2/20/2025.

Ordering

Stock and prices are a snapshot from the Adom parts search on 2026-10-21; check the distributor before ordering. DigiKey lists the part as Active. JLCPCB/LCSC search for C1812C124J1GACTU returned no part on 2026-10-21.

Part number

C ceramic | 1812 case size | C standard series | 124 = 12 x 10^4 pF = 0.12 uF | J +/-5 % | 1 = 100 V | G = C0G | A failure rate not applicable | C 100 % matte Sn termination | TU 7 inch reel, unmarked (datasheet p.1 and p.2). The thickness is not in the part number: Table 1B (p.8) gives code GH for 0.12 uF at 100 V in 1812, and Table 2A (p.10) gives GH = 1.40 +/-0.15 mm.

Manufacturer and resources

Pins

A ceramic capacitor has no polarity: either terminal may face either way (datasheet p.2, "non-polar device").

Land pattern: KiCad footprint vs KEMET

Land pattern

The footprint is KiCad's standard `C_1812_4532Metric`, and this guide lays its pads over KEMET's recommended IPC-7351 land (datasheet p.12, density level B) at true scale. Land centres, length and gap are identical; KiCad's pads are 0.10 mm narrower (3.40 vs 3.50 mm) and have rounded corners. Use it to decide whether to keep the KiCad pads or widen them to KEMET's level B before layout. The comparison, with KEMET's three density levels

3D model

The model is KEMET's own STEP for this part number, downloaded by plain HTTP from KEMET's component documentation service. KEMET's file (CCS_CCSTD_1812_L4.8W3.5T1.55B0.6) is Y-up with a corner at the origin; C1812C124J1GACTU.step is the same package solid moved by one rigid transform (rotate +90 degrees about X, then translate) so it is Z-up, seated on z = 0 and centred on the footprint origin, with its face colours copied over and its volume unchanged. KEMET's file also carries a "KEMET" logo as three 5 um thick solids on top of the ceramic, coloured only with SolidWorks' default lavender. The real part has no marking (KEMET supplies C0G parts unmarked only, p.15), so the board model leaves the logo out. The download itself is kept unchanged as vendor/C1812C124J1GACTU-kemet-original.step, and every step is recorded in provenance/C1812C124J1GACTU.step.json.

The model is drawn at the top of every printed range: 4.80 x 3.50 x 1.55 mm against L 4.50 +/-0.30, W 3.20 +/-0.30 and, for this part's thickness code GH, T 1.40 +/-0.15 mm. Its terminal band measures 0.88 mm on the top face, inside B 0.60 +/-0.35 mm. A real part will usually be smaller than the model in all three directions.

The page viewer shows c1812c124j1gactu-hero.glb: the clean model plus nonphysical reference artwork drawn under it to the adom-hero standard (adom/component-hero): the footprint's pads as teal dashed outlines at 50 % opacity, its silkscreen at 70 % transparency and the pad numbers 1 and 2. The part is non-polar, so no pin-1 dot is added. The artwork never goes into the STEP, package-reference.glb or the board LODs.

Model checked against the printed dimensions

The model was rendered in orthographic top, bottom, side and end views at true scale and laid over a drawing made at the same scale from the printed limits (nominal outline, tolerance limits, allowed terminal band). Every dimension is inside the printed range: L 4.800 mm (4.20 to 4.80), W 3.500 mm (2.90 to 3.50), T/H 1.550 mm (1.25 to 1.55), B (band width), top 0.877 mm (0.25 to 0.95), B (band width), bottom 0.877 mm (0.25 to 0.95).

Source: datasheet C1003_C0G p.3 (1812: L 4.50 +/-0.30, W 3.20 +/-0.30, B 0.60 +/-0.35, S 2.30 min) and p.8 + p.10 (0.12 uF, 100 V: thickness code GH, T 1.40 +/-0.15 mm).

Board levels of detail

Clean board-use GLBs (no footprint pads, outlines, labels or silkscreen) in four levels, all in the same Z-up, metre, footprint-origin pose as the STEP. Previews are rendered from each GLB.

CAD files

Datasheet figures

The pages this record cites, cropped from the datasheet:

Sources and license

• KEMET datasheet C1003_C0G, 2/20/2025 (https://content.kemet.com/datasheets/KEM_C1003_C0G_SMD.pdf), sha256 02d179914aeb9585eb2229ba8e18ef9d6b01c77c056de2af295d6950a2a5cc0d
• KEMET 3D model: https://search.kemet.com/component-documentation/download/step/C1812C124J1GACTU.step, sha256 b5d45febdee8defce1c3da229b540ed0a72760aeaa02501c728f7f8143eb6de7, 2026-10-21
• KiCad library footprint: Capacitor_SMD.pretty/C_1812_4532Metric.kicad_mod
• Distributor numbers, stock and prices: Mouser, DigiKey and JLCPCB/LCSC through the Adom parts search, 2026-10-21

Original Adom content is CC-BY-4.0. KEMET's STEP, its derivatives and the datasheet keep KEMET's terms and the KiCad footprint keeps its upstream license (CC-BY-SA 4.0 with the KiCad library exception); see LICENSE. provenance.json records every source and file hash; the scripts that built the checks are in provenance/tools/.

This is a catalog record for the part, not a manufacturing approval: check KEMET's current specification for your design.