# MEB/CL21B Series Box-Type Metallized Polyester Film Capacitors

> Boxed metallized polyester (PET) film capacitors for general-purpose DC circuits up to +125 °C. 100–630 VDC, 10 nF–2.2 µF.

- Series code: MEB/CL21B
- Product line: [Film capacitors](https://www.songtian-ste.com/en/products/film-capacitors/) › Metallized polyester (PET) film capacitors
- Part numbers: 129 · [part list (JSON)](https://www.songtian-ste.com/data/parts/cl21b.json)
- Page: https://www.songtian-ste.com/en/products/film-capacitors/cl21b/
- Chinese version: https://www.songtian-ste.com/zh/products/film-capacitors/cl21b/
- [Ask AI about this series](https://www.songtian-ste.com/en/products/film-capacitors/cl21b/?ask=Help%20me%20choose%20a%20part%20from%20the%20STE%20MEB%2FCL21B%20series.)

## Key specifications

| Parameter | Value |
| --- | --- |
| Rated voltage | 100 / 250 / 400 / 630 VDC |
| Capacitance | 10 nF–2.2 µF |
| Operating temperature | −40 °C to +125 °C |
| Dielectric | Metallized PET |
| Tolerance | ±5% / ±10% |
| Lead spacing | 10–27.5 mm |

## Engineering details

### Overview

Metallized polyester (PET) film capacitors with a non-inductive, self-healing winding in a flame-retardant plastic box, for bypass, blocking, coupling, decoupling, timing, oscillator and pulse circuits. Rated 100, 250, 400 and 630 VDC, 10 nF–2.2 µF, J ±5% or K ±10%. Lead spacing 10, 15, 22.5 and 27.5 mm. Operating temperature −40 °C to +125 °C, with voltage derating above +105 °C.

#### Series features

- Metallized PET film, non-inductive and self-healing, in a plastic box
- Rated 100 / 250 / 400 / 630 VDC; 10 nF to 2.2 µF
- Flame-retardant case and resin
- Lead spacing 10, 15, 22.5 and 27.5 mm

#### Typical applications

- General-purpose bypass, blocking, coupling and decoupling in DC circuits
- Timing and oscillator circuits; validate PET dielectric absorption, drift and frequency behavior
- Pulse circuits (dV/dt, peak-current, repetition-rate and temperature-rise limits on request)
- High-temperature PCB assemblies up to +125 °C; apply voltage derating and validate lifetime

### Specifications

|   |   |
| --- | --- |
| Product type | Boxed metallized polyester DC film capacitor for bypass, blocking, coupling, decoupling, timing, oscillator and pulse circuits; not a safety capacitor, not for reflow soldering |
| Construction | Metallized polyethylene terephthalate (PET) film · non-inductive winding · flame-retardant case and resin · radial leads |
| Self-healing | Yes |
| Rated DC voltage | 100 · 250 · 400 · 630 VDC |
| Capacitance range | 100 / 250 / 400 VDC: 10 nF–2.2 µF · 630 VDC: 10 nF–1.5 µF |
| Capacitance tolerance | J ±5% · K ±10% |
| Operating temperature | −40 °C to +125 °C |
| Voltage derating above +105 °C | 1.25% of UR per °C from +105 °C to +125 °C; 75% of UR at +125 °C when applied linearly. Derating curve on request. |
| Climatic category | 40/100/21 |
| Storage temperature | +15 °C to +35 °C |
| Dissipation factor | tan δ ≤1.0% at 1 kHz, 1.0 Vrms, 20 °C |
| Insulation resistance, UR >100 V, C ≤0.33 µF | ≥30,000 MΩ at 100 VDC, 60 s |
| Insulation resistance, UR >100 V, C >0.33 µF | Time constant IR × C ≥10,000 s at 100 VDC, 60 s |
| Insulation resistance, UR ≤100 V, C ≤0.33 µF | ≥15,000 MΩ at 10 VDC, 60 s |
| Insulation resistance, UR ≤100 V, C >0.33 µF | Time constant IR × C ≥5,000 s at 10 VDC, 60 s |
| Voltage proof, terminal to terminal | 1.6 × UR for 5 s |
| AC operation | DC-rated only; do not use in AC, resonant or capacitive-dropper circuits without frequency, current and lifetime data from STE |
| Safety class | No X/Y class and no agency approval; do not use across the line or line to earth |
| Flame retardancy | Flame-retardant case and resin |
| Body dimensions | W 13–32 · H 11–22 · T 5–13 mm, ±0.5 mm, depending on voltage and capacitance |
| Lead spacing | 10 · 15 · 22.5 · 27.5 mm, ±1.0 mm |
| Lead diameter | 0.6 ±0.05 mm at 10 mm spacing · 0.8 ±0.05 mm at 15–27.5 mm spacing |
| Lead forms and packing | Long straight · inner-bent · straight taped · bent taped |
| Taping | Tape dimensions specified for 10, 15 and 20–22.5 mm lead spacing; 27.5 mm packing on request |
| Lead forming | Inner-bent H1 <5 mm for P ≤10 mm and <6 mm for P >10 mm; long-lead tolerance changes at 6 mm |
| Soldering profile, PP | Preheat ≤110 °C · soldering ≤120 °C · ≤15 s |
| Soldering profile, PE | Preheat ≤125 °C · soldering ≤160 °C · ≤15 s |
| Hand soldering | 350 °C max. · 3 s max. · ≥2 mm from the coating |
| Reflow soldering | Not permitted; film shrinkage can degrade performance |
| Environmental compliance | RoHS and REACH compliant; bromine-free and halogen-free. Material declarations on request. |
| Further data | On request: clearing energy, capacitance loss and end-of-life limits · storage humidity and shelf life · dV/dt, K0, peak and repetitive current, pulse energy and repetition rate · dielectric absorption, capacitance drift, temperature coefficient and frequency dependence · ESR, ESL, impedance, self-resonant frequency, permissible voltage and current versus frequency, temperature rise · UL 94 class · loaded-life, high-temperature endurance, pulse-life, damp-heat, overload, thermal-cycle, vibration and lead-strength test results |

### Variants

Ranges by dielectric, package and lead style within this series.

| Variant | Body dimensions | Rated voltage / capacitance | Dielectric / tolerance / package | Lead / land pattern | Notes |
| --- | --- | --- | --- | --- | --- |
| N · 10 mm | W 13 · H 11–12 · T 5–6 mm | 100 VDC: 10 nF–1 µF · 250 VDC: 10–220 nF · 400 VDC: 10–150 nF · 630 VDC: 10–68 nF | Metallized PET · J/K · boxed | P 10 ±1.0 · d 0.6 ±0.05 mm | Compact size; 5 and 7.5 mm lead spacing on request. |
| Q · 15 mm | W 18 · H 11–19 · T 6–11 mm | 100 VDC: 1.5 µF · 250 VDC: 330 nF–1.5 µF · 400 VDC: 220–680 nF · 630 VDC: 100–330 nF | Metallized PET · J/K · boxed | P 15 ±1.0 · d 0.8 ±0.05 mm | Mid-range values for filtering, timing and pulse use; check stability and current data per part number. |
| T · 22.5 mm | W 26.5 · H 17–22 · T 8.5–12 mm | 100/250 VDC: 2.2 µF · 400 VDC: 1–1.5 µF · 630 VDC: 470 nF–1 µF | Metallized PET · J/K · boxed | P 22.5 ±1.0 · d 0.8 ±0.05 mm | Higher capacitance; verify ripple loss, hot-spot rise and mechanical support. |
| V · 27.5 mm | W 32 · H 20–22 · T 11–13 mm | 400 VDC: 2.2 µF · 630 VDC: 1.5 µF | Metallized PET · J/K · boxed | P 27.5 ±1.0 · d 0.8 ±0.05 mm | Largest body; packing on request. Support the body against vibration. |

### Selection guide

Start with the duty: signal, timing or pulse. Then check DC voltage, capacitance, dielectric absorption and drift, frequency loss, pulse current, derating above +105 °C, lifetime and dimensions.

1. **Define electrical and stability requirements**
   Specify DC bias, AC ripple, frequency spectrum, peak voltage, rise and fall time, dV/dt, repetition rate, RMS current, allowed timing or drift error, abnormal transients, ambient and case temperature, and service hours.
2. **Select voltage, capacitance and lead spacing**
   The series covers 100–630 VDC, 10 nF–2.2 µF and 10–27.5 mm lead spacing. For other voltages, values below 10 nF or above the listed maximum, and 5 or 7.5 mm lead spacing, request the part specification.
3. **Check PET stability and pulse stress**
   Obtain dielectric absorption, capacitance and loss versus temperature and frequency, drift, dV/dt, repetitive current, ESR, impedance, self-resonance and temperature-rise data for the selected part number.
4. **Apply temperature derating and validate lifetime**
   Reduce the rated voltage by 1.25% per °C above +105 °C. Check the derating curve, maximum case or hot-spot temperature and loaded-life data against the actual waveform and target hours.
5. **Confirm dimensions and assembly**
   Match the part number to marking, voltage, capacitance, tolerance, W/H/T, lead spacing, lead form, packing and soldering profile. Do not use reflow soldering; validate lead forming, cleaning, vibration and thermal cycling.

### Design notes

#### Validate the actual duty

Loss, pulse and lifetime limits on request. Validate the actual waveform, timing accuracy, ripple and thermal environment.

#### Timing and oscillator circuits need stable capacitance

PET dielectric absorption and drift can affect timing. Obtain capacitance versus temperature and frequency, dielectric absorption, aging and tolerance stability for the circuit error budget.

#### Calculate pulse and ripple heating from the measured spectrum

Use I = C·dV/dt and the measured spectrum, then combine repetitive and RMS current with ESR and thermal resistance.

#### Derate above +105 °C and validate lifetime

Applied linearly, the 1.25%/°C derating reaches 75% of rated voltage at +125 °C. Obtain the derating curve and loaded-life data; maximum temperature alone does not prove endurance.

#### Ratings outside the standard range

For values above 2.2 µF or below 10 nF, voltages other than 100–630 VDC, or 5 and 7.5 mm lead spacing, request the construction, loss and current limits, drawing and qualification report.

#### Marking and assembly

Check marking and dimensions at sample approval. Do not use reflow soldering, keep forming stress away from the seal, and validate cleaning, vibration and thermal cycling.

### Part numbering

Example ordering code. Not every combination is available.

`LB · 2A · 103 · K · N · 1 · B0 · 130 · 110 · 050 · E · S · 0`

| Code | Meaning |
| --- | --- |
| LB | Series code: MEB/CL21B |
| 2A | Rated voltage code: 2A = 100 VDC; 2E = 250 VDC, 2G = 400 VDC, 2J = 630 VDC |
| 103 | Capacitance code: 103 = 10 nF |
| K | Capacitance tolerance: K = ±10%, J = ±5% |
| N | Lead spacing: N = 10 mm; Q = 15, T = 22.5, V = 27.5 mm |
| 1 | Lead form: 1 = long straight, 2 = inner-bent, 5 = straight taped, 6 = bent taped |
| B0 | Lead length code: B0 = 20.0 mm |
| 130 | Body width: 130 = 13.0 mm |
| 110 | Body height: 110 = 11.0 mm |
| 050 | Body thickness: 050 = 5.0 mm |
| E | Environmental code: E = RoHS, F = RoHS and halogen-free |
| S | STE internal control code, first field |
| 0 | STE internal control code, second field |

## Datasheets & approval documents

- [Datasheet: MEB/CL21B series box-type metallized polyester (PET) film capacitors — short-form datasheet (2023-10)](https://www.songtian-ste.com/documents/source-cn/%E9%87%91%E5%B1%9E%E8%86%9C%E7%94%B5%E5%AE%B9%E5%99%A8%E7%B3%BB%E5%88%97%E4%BA%A7%E5%93%81%E8%A7%84%E6%A0%BC%E4%B9%A6/MPE%E8%81%9A%E8%84%82%E8%86%9C%E7%94%B5%E5%AE%B9%E5%99%A8/%E7%9B%92%E5%BC%8F%E9%87%91%E5%B1%9E%E5%8C%96%E8%81%9A%E9%85%AF%E8%86%9C%E7%94%B5%E5%AE%B9%E5%99%A8%28MEB%20CL21B%29%E7%AE%80%E7%89%88%E8%A7%84%E6%A0%BC%E4%B9%A6-202310.pdf) — PDF · Chinese · 2023-10 · 281 KB

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