steve/melf-diode

Surface-mount diode packages MELF (DO-213AB), MiniMELF (SOD-80) and MicroMELF, from Vishay's package drawings.

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Parameters

Preset3 sizes

Package3 options

MELF: DO-213AB, plastic. MiniMELF: SOD-80, glass. MicroMELF: glass.

Defaults built

part.py 77 lines · Python · STEVE runtime · checked

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"""Surface-mount diode in a MELF package (MELF DO-213AB, MiniMELF SOD-80 or MicroMELF), by Vishay's package drawings. Lying on the XY plane

(the board) with its axis along X and centred on the origin in X and Y: the body between two metal end caps, and the cathode band on the body

at the -X end. Each end cap is its own solid. Dimensions from Vishay's drawings; see the README."""

from steve import Model

package = "MiniMELF" # MELF (DO-213AB, plastic), MiniMELF (SOD-80) or MicroMELF

# package: (other name, body section, length, end cap diameter, end cap length, body across, body across the corners), ranges (min, max) in

# mm; None where the drawing doesn't give it.

# Vishay Semiconductors, "Package Dimensions for ESD-, Zener-, Small Signal Switching-, and Schottky Diodes", document number 80128,

# revision 1.4, 11-Oct-2022 (https://www.vishay.com/docs/80128/package_information.pdf), "PACKAGE DIMENSIONS in millimeters (inches)":

# MELF DO-213AB (PLASTIC) page 33 (drawing S8-V-3453.03-001, 13 May 2009): body D1 2.41 to 2.67, end caps D2 = D1 + 0 to 0.2 (here

# 2.41 to 2.87, whose middle is D1's middle + 0.1), end caps 0.46 to 0.56 long, 4.7 to 5.2 long;

# MiniMELF (SOD-80) page 37 (drawing 6.560-5005.01-4, rev. 8, 07 Jun 2006): end caps 1.4 to 1.6 across and 0.47 max. long (the only

# value given, used as is), 3.3 to 3.7 long;

# MicroMELF page 35 (drawing 6.560-5007.01-4, rev. 13, 07 Jun 2006): end caps 1.1 to 1.2 across and 0.15 to 0.25 long, 1.8 to 2.0 long;

# the glass is a rounded square, 0.6 from the axis to its flat ("surface plan") sides, so 1.2 across them, and under 1.35 across the

# corners (1.35 used).

OUTLINES = {

"MELF": ("DO-213AB", "round", (4.7, 5.2), (2.41, 2.87), (0.46, 0.56), (2.41, 2.67), None),

"MiniMELF": ("SOD-80", "round", (3.3, 3.7), (1.4, 1.6), (0.47, 0.47), None, None),

"MicroMELF": ("", "square", (1.8, 2.0), (1.1, 1.2), (0.15, 0.25), (1.2, 1.2), (1.35, 1.35)),

}

# Proportions, for looks (the drawings show these but don't dimension them): the glass body of the MiniMELF is GLASS of its end caps'

# diameter; the cathode band runs from the -X end cap BAND of the way along the body.

GLASS = 0.92

BAND = 0.2

def mid(pair):

return (pair[0] + pair[1]) / 2

other, section, LEN, CAP_D, CAP_L, ACROSS, CORNERS = OUTLINES[package]

length, cap_d, cap_l = mid(LEN), mid(CAP_D), mid(CAP_L)

across = mid(ACROSS) if ACROSS else GLASS * cap_d

# The part rests on whichever is lower: the end caps or the body (MicroMELF's flat glass sides).

axis_z = max(cap_d, across) / 2

inside = length / 2 - cap_l

band = BAND * 2 * inside

model = Model()

# Each cylinder starts at `at` and runs along +X.

for tag, side in (("cathode", -1), ("anode", 1)):

model.cylinder(f"{tag}_cap", cap_d / 2, cap_l, at=(-length / 2 if side < 0 else inside, 0, axis_z), direction=(1, 0, 0), op="new",

body=f"{tag}_cap_body", name="End caps")

if section == "round":

model.cylinder("band", across / 2, band, at=(-inside, 0, axis_z), direction=(1, 0, 0), op="new", body="band_body",

name="Cathode band")

model.cylinder("body", across / 2, 2 * inside - band, at=(-inside + band, 0, axis_z), direction=(1, 0, 0), op="new", body="body_body",

name="Body")

else:

# A square across the flats with its corners rounded to the given size across the corners: the corner radius r makes the diagonal

# 2 * (h * sqrt(2) - r * (sqrt(2) - 1)) for half-width h.

h = across / 2

r = (h * 2 ** 0.5 - mid(CORNERS) / 2) / (2 ** 0.5 - 1)

for tag, x0, x1 in (("band", -inside, -inside + band), ("body", -inside + band, inside)):

model.plane(f"{tag}_plane", on="YZ", offset=x0, name="Body")

with model.sketch(f"{tag}_sketch", on=f"{tag}_plane", name="Body") as sk:

for i, (sy, sz) in enumerate(((1, 1), (-1, 1), (-1, -1), (1, -1))):

sk.arc(f"{tag}_corner_{i}", (sy * (h - r), axis_z + sz * (h - r)), r, 90 * i, 90 * i + 90)

sk.line(f"{tag}_top", (h - r, axis_z + h), (-h + r, axis_z + h))

sk.line(f"{tag}_left", (-h, axis_z + h - r), (-h, axis_z - h + r))

sk.line(f"{tag}_bottom", (-h + r, axis_z - h), (h - r, axis_z - h))

sk.line(f"{tag}_right", (h, axis_z - h + r), (h, axis_z + h - r))

model.extrude(tag, f"{tag}_sketch", distance=x1 - x0, op="new", body=f"{tag}_body", name="Cathode band" if tag == "band" else "Body")

# Materials, for looks and a rough mass. MELF's body is moulded epoxy over a glass body (Vishay GL41 data sheet), ptfe (2.07) the nearest

# to a silica-filled epoxy (about 1.9 to 2.0) in the material list; MiniMELF's and MicroMELF's bodies are glass, soda-lime glass; the end

# caps are plated metal, copper; the band is marking ink, shown in ptfe.

if package == "MELF":

model.material("ptfe", bodies=["body_body"], color="#2b2d30")

model.material("ptfe", bodies=["band_body"], color="#c8c8c4")

else:

model.material("glass-soda-lime", bodies=["body_body"], color="#c0602a")

model.material("ptfe", bodies=["band_body"], color="#1d1d1f")

model.material("copper", bodies=["cathode_cap_body", "anode_cap_body"], color="#c9ccd1")

result = model.result()

"""Surface-mount diode in a MELF package (MELF DO-213AB, MiniMELF SOD-80 or MicroMELF), by Vishay's package drawings. Lying on the XY plane
(the board) with its axis along X and centred on the origin in X and Y: the body between two metal end caps, and the cathode band on the body
at the -X end. Each end cap is its own solid. Dimensions from Vishay's drawings; see the README."""
from steve import Model

package = "MiniMELF"  # MELF (DO-213AB, plastic), MiniMELF (SOD-80) or MicroMELF

# package: (other name, body section, length, end cap diameter, end cap length, body across, body across the corners), ranges (min, max) in
# mm; None where the drawing doesn't give it.
# Vishay Semiconductors, "Package Dimensions for ESD-, Zener-, Small Signal Switching-, and Schottky Diodes", document number 80128,
# revision 1.4, 11-Oct-2022 (https://www.vishay.com/docs/80128/package_information.pdf), "PACKAGE DIMENSIONS in millimeters (inches)":
#   MELF DO-213AB (PLASTIC) page 33 (drawing S8-V-3453.03-001, 13 May 2009): body D1 2.41 to 2.67, end caps D2 = D1 + 0 to 0.2 (here
#     2.41 to 2.87, whose middle is D1's middle + 0.1), end caps 0.46 to 0.56 long, 4.7 to 5.2 long;
#   MiniMELF (SOD-80) page 37 (drawing 6.560-5005.01-4, rev. 8, 07 Jun 2006): end caps 1.4 to 1.6 across and 0.47 max. long (the only
#     value given, used as is), 3.3 to 3.7 long;
#   MicroMELF page 35 (drawing 6.560-5007.01-4, rev. 13, 07 Jun 2006): end caps 1.1 to 1.2 across and 0.15 to 0.25 long, 1.8 to 2.0 long;
#     the glass is a rounded square, 0.6 from the axis to its flat ("surface plan") sides, so 1.2 across them, and under 1.35 across the
#     corners (1.35 used).
OUTLINES = {
    "MELF": ("DO-213AB", "round", (4.7, 5.2), (2.41, 2.87), (0.46, 0.56), (2.41, 2.67), None),
    "MiniMELF": ("SOD-80", "round", (3.3, 3.7), (1.4, 1.6), (0.47, 0.47), None, None),
    "MicroMELF": ("", "square", (1.8, 2.0), (1.1, 1.2), (0.15, 0.25), (1.2, 1.2), (1.35, 1.35)),
}
# Proportions, for looks (the drawings show these but don't dimension them): the glass body of the MiniMELF is GLASS of its end caps'
# diameter; the cathode band runs from the -X end cap BAND of the way along the body.
GLASS = 0.92
BAND = 0.2


def mid(pair):
    return (pair[0] + pair[1]) / 2


other, section, LEN, CAP_D, CAP_L, ACROSS, CORNERS = OUTLINES[package]
length, cap_d, cap_l = mid(LEN), mid(CAP_D), mid(CAP_L)
across = mid(ACROSS) if ACROSS else GLASS * cap_d
# The part rests on whichever is lower: the end caps or the body (MicroMELF's flat glass sides).
axis_z = max(cap_d, across) / 2
inside = length / 2 - cap_l
band = BAND * 2 * inside
model = Model()
# Each cylinder starts at `at` and runs along +X.
for tag, side in (("cathode", -1), ("anode", 1)):
    model.cylinder(f"{tag}_cap", cap_d / 2, cap_l, at=(-length / 2 if side < 0 else inside, 0, axis_z), direction=(1, 0, 0), op="new",
                   body=f"{tag}_cap_body", name="End caps")
if section == "round":
    model.cylinder("band", across / 2, band, at=(-inside, 0, axis_z), direction=(1, 0, 0), op="new", body="band_body",
                   name="Cathode band")
    model.cylinder("body", across / 2, 2 * inside - band, at=(-inside + band, 0, axis_z), direction=(1, 0, 0), op="new", body="body_body",
                   name="Body")
else:
    # A square across the flats with its corners rounded to the given size across the corners: the corner radius r makes the diagonal
    # 2 * (h * sqrt(2) - r * (sqrt(2) - 1)) for half-width h.
    h = across / 2
    r = (h * 2 ** 0.5 - mid(CORNERS) / 2) / (2 ** 0.5 - 1)
    for tag, x0, x1 in (("band", -inside, -inside + band), ("body", -inside + band, inside)):
        model.plane(f"{tag}_plane", on="YZ", offset=x0, name="Body")
        with model.sketch(f"{tag}_sketch", on=f"{tag}_plane", name="Body") as sk:
            for i, (sy, sz) in enumerate(((1, 1), (-1, 1), (-1, -1), (1, -1))):
                sk.arc(f"{tag}_corner_{i}", (sy * (h - r), axis_z + sz * (h - r)), r, 90 * i, 90 * i + 90)
            sk.line(f"{tag}_top", (h - r, axis_z + h), (-h + r, axis_z + h))
            sk.line(f"{tag}_left", (-h, axis_z + h - r), (-h, axis_z - h + r))
            sk.line(f"{tag}_bottom", (-h + r, axis_z - h), (h - r, axis_z - h))
            sk.line(f"{tag}_right", (h, axis_z - h + r), (h, axis_z + h - r))
        model.extrude(tag, f"{tag}_sketch", distance=x1 - x0, op="new", body=f"{tag}_body", name="Cathode band" if tag == "band" else "Body")
# Materials, for looks and a rough mass. MELF's body is moulded epoxy over a glass body (Vishay GL41 data sheet), ptfe (2.07) the nearest
# to a silica-filled epoxy (about 1.9 to 2.0) in the material list; MiniMELF's and MicroMELF's bodies are glass, soda-lime glass; the end
# caps are plated metal, copper; the band is marking ink, shown in ptfe.
if package == "MELF":
    model.material("ptfe", bodies=["body_body"], color="#2b2d30")
    model.material("ptfe", bodies=["band_body"], color="#c8c8c4")
else:
    model.material("glass-soda-lime", bodies=["body_body"], color="#c0602a")
    model.material("ptfe", bodies=["band_body"], color="#1d1d1f")
model.material("copper", bodies=["cathode_cap_body", "anode_cap_body"], color="#c9ccd1")
result = model.result()

pypart.toml 36 lines · TOML

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name = "steve/melf-diode"

version = "1.0.0"

runtime = "steve"

license = "MIT"

summary = "Surface-mount diode packages MELF (DO-213AB), MiniMELF (SOD-80) and MicroMELF, from Vishay's package drawings."

description = """Cylindrical surface-mount diode packages for board layouts and enclosures: the body between two metal end caps, each end cap its own solid, and the cathode band. MELF (DO-213AB) is the plastic package; MiniMELF (SOD-80) and MicroMELF are glass. Dimensions from Vishay's package drawings (document 80128). See the README."""

tags = ["diode", "smd", "melf", "minimelf", "micromelf", "do-213ab", "sod-80", "electronics"]

[parameters.package]

type = "choice"

default = "MiniMELF"

choices = ["MELF", "MiniMELF", "MicroMELF"]

label = "Package"

description = "MELF: DO-213AB, plastic. MiniMELF: SOD-80, glass. MicroMELF: glass."

[[presets]]

id = "MELF"

title = "MELF (DO-213AB) diode package, Vishay drawing"

params = { package = "MELF" }

aliases = ["DO-213AB", "MELF diode", "DO-213AB diode"]

standard = "Vishay 80128"

[[presets]]

id = "MiniMELF"

title = "MiniMELF (SOD-80) diode package, Vishay drawing"

params = { package = "MiniMELF" }

aliases = ["SOD-80", "MiniMELF diode", "SOD-80 diode"]

standard = "Vishay 80128"

[[presets]]

id = "MicroMELF"

title = "MicroMELF diode package, Vishay drawing"

params = { package = "MicroMELF" }

aliases = ["MicroMELF diode"]

standard = "Vishay 80128"

name = "steve/melf-diode"
version = "1.0.0"
runtime = "steve"
license = "MIT"
summary = "Surface-mount diode packages MELF (DO-213AB), MiniMELF (SOD-80) and MicroMELF, from Vishay's package drawings."
description = """Cylindrical surface-mount diode packages for board layouts and enclosures: the body between two metal end caps, each end cap its own solid, and the cathode band. MELF (DO-213AB) is the plastic package; MiniMELF (SOD-80) and MicroMELF are glass. Dimensions from Vishay's package drawings (document 80128). See the README."""
tags = ["diode", "smd", "melf", "minimelf", "micromelf", "do-213ab", "sod-80", "electronics"]

[parameters.package]
type = "choice"
default = "MiniMELF"
choices = ["MELF", "MiniMELF", "MicroMELF"]
label = "Package"
description = "MELF: DO-213AB, plastic. MiniMELF: SOD-80, glass. MicroMELF: glass."

[[presets]]
id = "MELF"
title = "MELF (DO-213AB) diode package, Vishay drawing"
params = { package = "MELF" }
aliases = ["DO-213AB", "MELF diode", "DO-213AB diode"]
standard = "Vishay 80128"

[[presets]]
id = "MiniMELF"
title = "MiniMELF (SOD-80) diode package, Vishay drawing"
params = { package = "MiniMELF" }
aliases = ["SOD-80", "MiniMELF diode", "SOD-80 diode"]
standard = "Vishay 80128"

[[presets]]
id = "MicroMELF"
title = "MicroMELF diode package, Vishay drawing"
params = { package = "MicroMELF" }
aliases = ["MicroMELF diode"]
standard = "Vishay 80128"

README.md 42 lines · Markdown

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MELF diode package

Cylindrical surface-mount diode packages: MELF (DO-213AB, plastic), MiniMELF (SOD-80, glass) and MicroMELF (glass), as Vishay draws them. The package lies on the XY plane (the board) with its axis along X, centred on the origin in X and Y. It is the body between two metal end caps, with the cathode band on the body at the -X end. Each end cap is its own solid.

Source

Vishay Semiconductors, "Package Dimensions for ESD-, Zener-, Small Signal Switching-, and Schottky Diodes", document number 80128, revision 1.4, 11-Oct-2022, https://www.vishay.com/docs/80128/package_information.pdf. Each page is "PACKAGE DIMENSIONS in millimeters (inches)":

MELF DO-213AB (PLASTIC): page 33, drawing S8-V-3453.03-001, 13 May 2009. The same drawing is in Vishay's GL41 data sheet, document 88546, revision 18-May-2021.
MiniMELF (SOD-80): page 37, drawing 6.560-5005.01-4, rev. 8, 07 Jun 2006.
MicroMELF: page 35, drawing 6.560-5007.01-4, rev. 13, 07 Jun 2006.

Package	Length	End cap diameter	End cap length	Body
MELF	4.7–5.2	D2 = D1 + 0 to 0.2	0.46–0.56	D1 = 2.41–2.67
MiniMELF	3.3–3.7	1.4–1.6	0.47 max.	not given
MicroMELF	1.8–2.0	1.1–1.2	0.15–0.25	glass: 0.6 from the axis to its flat sides; under 1.35 across the corners

The model uses the middle of each range. MELF's end caps are 0.1 larger than its body, the middle of D1 + 0 to 0.2. MiniMELF's end cap length is given only as 0.47 max., so 0.47 is used. MicroMELF's glass is a square 1.2 across its flat sides with its corners rounded to 1.35 across, the limit given; the drawing's sides bulge slightly (radius over 2.5), and they are modelled flat. MicroMELF rests on its glass's flat side, the others on their end caps.

Proportions, stated plainly. The drawings show these but don't dimension them:

MiniMELF's glass body is 0.92 of its end caps' diameter. The drawing shows it a little smaller than the caps.
The cathode band is flush with the body. It runs from the -X end cap 0.2 of the way along the body. The drawings place it near that end cap but don't dimension it.
The body runs from end cap to end cap. The small gap the glass drawings show at one end isn't modelled.

Materials and mass. MELF's body is moulded epoxy over a glass body (Vishay's GL41 data sheet). It is ptfe (2.07), the nearest in the material list to a silica-filled epoxy (about 1.9 to 2.0). MiniMELF's and MicroMELF's bodies are glass, soda-lime glass. The end caps are plated metal, shown as copper. The band is marking ink, shown in ptfe. Vishay's data sheets give each package's weight:

Package	Model	Vishay's weight	Data sheet
MELF	91 mg	0.114 g	GL41, document 88546, revision 18-May-2021 (vishay.com)
MiniMELF	25 mg	approx. 31 mg	LL4148-M, document 81162, rev. 1.4, 25-Jun-2024 (vishay.com)
MicroMELF	9 mg	approx. 12 mg	MCL4151, document 85567, rev. 2.2, 25-Jun-2024 (vishay.com)

The models come out lighter than stated, because the metal slugs and the die inside the body aren't modelled.

Catalogue models

The old catalogue's D_MELF, D_MiniMELF and D_MicroMELF entries have no models to measure. Each names its package, and each maps to Vishay's drawing of that package. MELF is DO-213AB, and its plastic drawing is used, which is the one that dimensions the body. Vishay also draws a glass DO-213AB, 2.4 to 2.6 across, which isn't offered.

The family is shared with do214-diode (SMA, SMB and SMC). The other surface-mount diode packages in it aren't read here; see COVERAGE.md.

# MELF diode package

## Source

Vishay Semiconductors, "Package Dimensions for ESD-, Zener-, Small Signal Switching-, and Schottky Diodes", document number 80128, revision 1.4, 11-Oct-2022, <https://www.vishay.com/docs/80128/package_information.pdf>. Each page is "PACKAGE DIMENSIONS in millimeters (inches)":

- MELF DO-213AB (PLASTIC): page 33, drawing S8-V-3453.03-001, 13 May 2009. The same drawing is in Vishay's GL41 data sheet, document 88546, revision 18-May-2021.

- MiniMELF (SOD-80): page 37, drawing 6.560-5005.01-4, rev. 8, 07 Jun 2006.

- MicroMELF: page 35, drawing 6.560-5007.01-4, rev. 13, 07 Jun 2006.

|---|---|---|---|---|

| MELF | 4.7–5.2 | D2 = D1 + 0 to 0.2 | 0.46–0.56 | D1 = 2.41–2.67 |

| MiniMELF | 3.3–3.7 | 1.4–1.6 | 0.47 max. | not given |

| MicroMELF | 1.8–2.0 | 1.1–1.2 | 0.15–0.25 | glass: 0.6 from the axis to its flat sides; under 1.35 across the corners |

**Proportions, stated plainly.** The drawings show these but don't dimension them:

- MiniMELF's glass body is 0.92 of its end caps' diameter. The drawing shows it a little smaller than the caps.

- The cathode band is flush with the body. It runs from the -X end cap 0.2 of the way along the body. The drawings place it near that end cap but don't dimension it.

- The body runs from end cap to end cap. The small gap the glass drawings show at one end isn't modelled.

**Materials and mass.** MELF's body is moulded epoxy over a glass body (Vishay's GL41 data sheet). It is ptfe (2.07), the nearest in the material list to a silica-filled epoxy (about 1.9 to 2.0). MiniMELF's and MicroMELF's bodies are glass, soda-lime glass. The end caps are plated metal, shown as copper. The band is marking ink, shown in ptfe. Vishay's data sheets give each package's weight:

|---|---|---|---|

| MELF | 91 mg | 0.114 g | GL41, document 88546, revision 18-May-2021 (vishay.com) |

The models come out lighter than stated, because the metal slugs and the die inside the body aren't modelled.

## Catalogue models

The old catalogue's `D_MELF`, `D_MiniMELF` and `D_MicroMELF` entries have no models to measure. Each names its package, and each maps to Vishay's drawing of that package. MELF is DO-213AB, and its plastic drawing is used, which is the one that dimensions the body. Vishay also draws a glass DO-213AB, 2.4 to 2.6 across, which isn't offered.

The family is shared with `do214-diode` (SMA, SMB and SMC). The other surface-mount diode packages in it aren't read here; see `COVERAGE.md`.

# MELF diode package

Cylindrical surface-mount diode packages: MELF (DO-213AB, plastic), MiniMELF (SOD-80, glass) and MicroMELF (glass), as Vishay draws them. The package lies on the XY plane (the board) with its axis along X, centred on the origin in X and Y. It is the body between two metal end caps, with the cathode band on the body at the -X end. Each end cap is its own solid.

## Source

Vishay Semiconductors, "Package Dimensions for ESD-, Zener-, Small Signal Switching-, and Schottky Diodes", document number 80128, revision 1.4, 11-Oct-2022, <https://www.vishay.com/docs/80128/package_information.pdf>. Each page is "PACKAGE DIMENSIONS in millimeters (inches)":

- MELF DO-213AB (PLASTIC): page 33, drawing S8-V-3453.03-001, 13 May 2009. The same drawing is in Vishay's GL41 data sheet, document 88546, revision 18-May-2021.
- MiniMELF (SOD-80): page 37, drawing 6.560-5005.01-4, rev. 8, 07 Jun 2006.
- MicroMELF: page 35, drawing 6.560-5007.01-4, rev. 13, 07 Jun 2006.

| Package | Length | End cap diameter | End cap length | Body |
|---|---|---|---|---|
| MELF | 4.7–5.2 | D2 = D1 + 0 to 0.2 | 0.46–0.56 | D1 = 2.41–2.67 |
| MiniMELF | 3.3–3.7 | 1.4–1.6 | 0.47 max. | not given |
| MicroMELF | 1.8–2.0 | 1.1–1.2 | 0.15–0.25 | glass: 0.6 from the axis to its flat sides; under 1.35 across the corners |

The model uses the middle of each range. MELF's end caps are 0.1 larger than its body, the middle of D1 + 0 to 0.2. MiniMELF's end cap length is given only as 0.47 max., so 0.47 is used. MicroMELF's glass is a square 1.2 across its flat sides with its corners rounded to 1.35 across, the limit given; the drawing's sides bulge slightly (radius over 2.5), and they are modelled flat. MicroMELF rests on its glass's flat side, the others on their end caps.

**Proportions, stated plainly.** The drawings show these but don't dimension them:

- MiniMELF's glass body is 0.92 of its end caps' diameter. The drawing shows it a little smaller than the caps.
- The cathode band is flush with the body. It runs from the -X end cap 0.2 of the way along the body. The drawings place it near that end cap but don't dimension it.
- The body runs from end cap to end cap. The small gap the glass drawings show at one end isn't modelled.

**Materials and mass.** MELF's body is moulded epoxy over a glass body (Vishay's GL41 data sheet). It is ptfe (2.07), the nearest in the material list to a silica-filled epoxy (about 1.9 to 2.0). MiniMELF's and MicroMELF's bodies are glass, soda-lime glass. The end caps are plated metal, shown as copper. The band is marking ink, shown in ptfe. Vishay's data sheets give each package's weight:

| Package | Model | Vishay's weight | Data sheet |
|---|---|---|---|
| MELF | 91 mg | 0.114 g | GL41, document 88546, revision 18-May-2021 (vishay.com) |
| MiniMELF | 25 mg | approx. 31 mg | LL4148-M, document 81162, rev. 1.4, 25-Jun-2024 (vishay.com) |
| MicroMELF | 9 mg | approx. 12 mg | MCL4151, document 85567, rev. 2.2, 25-Jun-2024 (vishay.com) |

The models come out lighter than stated, because the metal slugs and the die inside the body aren't modelled.

## Catalogue models

The old catalogue's `D_MELF`, `D_MiniMELF` and `D_MicroMELF` entries have no models to measure. Each names its package, and each maps to Vishay's drawing of that package. MELF is DO-213AB, and its plastic drawing is used, which is the one that dimensions the body. Vishay also draws a glass DO-213AB, 2.4 to 2.6 across, which isn't offered.

The family is shared with `do214-diode` (SMA, SMB and SMC). The other surface-mount diode packages in it aren't read here; see `COVERAGE.md`.

Use this part

STEVE

Open in STEVE

Open it in STEVE The STEVE runtime runs in STEVE: open the part there, or download the code and bundle.

Get the code

curl -o part.py "https://pythonparts.org/p/steve/melf-diode/v/1.0.0/raw/part.py"

Raw files, bundle and API

part.py
pypart.toml
README.md
bundle.tar.gzthe package, as published

curl "https://pythonparts.org/api/v1/parts/steve/melf-diode/1.0.0"

The version's JSON (parameters, presets, files); add /build?name=value for a build at other values.

About this part

steve146 parts

Profile

Copper (pure)Copper alloys · Custom finish · 8.96 g/cm³
PTFEPlastics · Custom finish · 2.07 g/cm³
Soda-lime glassGlass · Custom finish · 2.52 g/cm³

Mass: 0.024 g

At the parameters shown in the viewer, 4 bodies.

License: MIT

Permissive: use, change and sell it; keep the copyright notice.

Runtime: STEVE
Requirements: None stated in the code
Built with: CadQuery 2.9.0.dev0
Published: Nov 6, 2026
Downloads: 0
Builds: 0
Stars: 0
Bundle: cb5ae616c508…

#diode #smd #melf #minimelf #micromelf #do-213ab #sod-80 #electronics

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Cylindrical surface-mount diode packages for board layouts and enclosures: the body between two metal end caps, each end cap its own solid, and the cathode band. MELF (DO-213AB) is the plastic package; MiniMELF (SOD-80) and MicroMELF are glass. Dimensions from Vishay's package drawings (document 80128). See the README.

MELF diode package

Source

MELF DO-213AB (PLASTIC): page 33, drawing S8-V-3453.03-001, 13 May 2009. The same drawing is in Vishay's GL41 data sheet, document 88546, revision 18-May-2021.
MiniMELF (SOD-80): page 37, drawing 6.560-5005.01-4, rev. 8, 07 Jun 2006.
MicroMELF: page 35, drawing 6.560-5007.01-4, rev. 13, 07 Jun 2006.

Package	Length	End cap diameter	End cap length	Body
MELF	4.7–5.2	D2 = D1 + 0 to 0.2	0.46–0.56	D1 = 2.41–2.67
MiniMELF	3.3–3.7	1.4–1.6	0.47 max.	not given
MicroMELF	1.8–2.0	1.1–1.2	0.15–0.25	glass: 0.6 from the axis to its flat sides; under 1.35 across the corners

Proportions, stated plainly. The drawings show these but don't dimension them:

MiniMELF's glass body is 0.92 of its end caps' diameter. The drawing shows it a little smaller than the caps.
The cathode band is flush with the body. It runs from the -X end cap 0.2 of the way along the body. The drawings place it near that end cap but don't dimension it.
The body runs from end cap to end cap. The small gap the glass drawings show at one end isn't modelled.

Package	Model	Vishay's weight	Data sheet
MELF	91 mg	0.114 g	GL41, document 88546, revision 18-May-2021 (vishay.com)
MiniMELF	25 mg	approx. 31 mg	LL4148-M, document 81162, rev. 1.4, 25-Jun-2024 (vishay.com)
MicroMELF	9 mg	approx. 12 mg	MCL4151, document 85567, rev. 2.2, 25-Jun-2024 (vishay.com)

The models come out lighter than stated, because the metal slugs and the die inside the body aren't modelled.

Catalogue models

The family is shared with do214-diode (SMA, SMB and SMC). The other surface-mount diode packages in it aren't read here; see COVERAGE.md.

1.0.0 Latest Nov 6, 2026 · 2 hours ago

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