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WhatSMDSign in

SMD marking

CH7

Marking codes are not standardised, and the same code is reused by unrelated makers for unrelated parts. Below is every part in our tables printed with it, and any printed with a code that is easy to misread as it, from the manufacturers' own marking tables.

Not sure which one you have?

Answer up to 4 quick questions and these 2 parts are ranked, with a meter test that settles it. It works on a dead part too.

The only part printed CH7 in our tables

SN74LVC1G86DRL

What it is
Logic gate
Maker
Texas Instruments
Package
Not recorded
Pins
5
Details
Single 2-Input Exclusive-OR Gate
Source
From the manufacturer's datasheet

Is it dead?

Voltage with the board powered; ohms from each pin to ground with it off.

Working, it reads

Supply pin at its voltage and the output doing what the datasheet says. Readings between pins depend on the part.

Dead, it reads

  • A pin near 0 Ω to ground or to the supply pin where an identical part does not read that: failed short.
  • Supply present, output stuck: failed, or its load has.
On the board:
A pin shorted to ground on the board can be anything on that net. Lift the pin to be sure.
Compare:
The surest reference is the same IC on a working board, measured pin by pin.
Watch for:
Its protection diodes can read like junctions between pins, even like a transistor. That proves nothing either way.

A dead part still carries its marking. A short or an open says it has failed, not that it is a different part.

Datasheetfor SN74LVC1G86DRL, opens in a new tab

Printed with a code easy to misread

This part is printed with a character that is easy to misread as what you typed. The odd one out is marked on each.

  • TPS2553DRVprinted CHTWSONLoad switch, 6 pins, Texas Instruments

    Printed CHT on the part. Easy to misread as CH7. Check that character with a loupe before you order anything.

    What it is
    Load switch
    Maker
    Texas Instruments
    Package
    WSON
    Pins
    6
    Details
    Precision Adjustable Current-Limited Power-Distribution Switches
    Source
    From the manufacturer's datasheet

    Is it dead?

    Voltage, board powered, black probe on ground.

    Working, it reads

    Switched on, the output pin sits at the input voltage. Switched off, it sits near 0 V.

    Dead, it reads

    • Output at the input voltage while switched off: the pass element has shorted.
    • Input present and switched on, no output: failed open, or shut down into a shorted load. Power off and measure output to ground.
    On the board:
    An output near 0 Ω to ground is usually the load. Lift the output pin to see which.
    Compare:
    If an identical part sits elsewhere on the board, measure it the same way: that is what this one should read.
    Watch for:
    The pinout and whether the enable is active high or low differ between parts. The datasheet gives both.

    A dead part still carries its marking. A short or an open says it has failed, not that it is a different part.

    Datasheetfor TPS2553DRV, opens in a new tab

Open this in the search to correct a character or try another package.