SMD code search: identify a part by its marking
2 parts are printed Z20B. 3 printed with a similar-looking code.
2 parts are printed Z20B
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.
Zener diode, all SOD-80, 2 pins. What differs:
TLZJ20BSOD-80Taitron ComponentsTaitron Components
- What it is
- Zener diode
- Maker
- Taitron Components
- Package
- SOD-80
- Pins
- 2
- Details
- SMD Zener Diodes (Leadless ) - 500mW
- Source
- Manufacturer datasheet
Is it dead?
Diode range for the forward check, part lifted, red probe on the anode. A bench supply for the Zener voltage.
Working, it reads
About 0.6 to 0.8 V forward and open in reverse on the diode range. Its Zener voltage shows only on a supply: feed it through a resistor that sets about 5 mA, cathode to positive, read quickly, and it should hold near its rated voltage.
Dead, it reads
- The same reading both ways round, near 0 V with a continuous beep or the same middling value: shorted.
- Open both ways, forward too: failed open.
- Holds well off its rated voltage on the supply test: drifted.
- A soft knee, or a voltage that creeps on the supply test: leaky.
- On the board
- this is a first look only: the meter reads every path between those pins, and a short can be a neighbour. Lift one leg before you condemn it.
- Compare:
- If an identical part sits elsewhere on the board, measure it the same way: that is what this one should read.
- Watch for:
- A meter's diode range stops at about 2 to 3 V, so almost every Zener reads open in reverse on it, good or bad; a 3 V meter may just show a 2.4 or 2.7 V part. Above about 3 V the meter cannot tell a Zener from a plain diode.
A dead part still carries its marking. A short or an open says it has failed, not that it is a different part.
GLZJ20BSOD-80PanjitPanjit
- What it is
- Zener diode
- Maker
- Panjit
- Package
- SOD-80
- Pins
- 2
- Details
- Zener diode: 18.63..19.59V, Zzt=55 , Izt=5mA, 500mW
- Source
- Published code list
Is it dead?
Diode range for the forward check, part lifted, red probe on the anode. A bench supply for the Zener voltage.
Working, it reads
About 0.6 to 0.8 V forward and open in reverse on the diode range. Its Zener voltage shows only on a supply: feed it through a resistor that sets about 5 mA, cathode to positive, read quickly, and it should hold near its rated voltage.
Dead, it reads
- The same reading both ways round, near 0 V with a continuous beep or the same middling value: shorted.
- Open both ways, forward too: failed open.
- Holds well off its rated voltage on the supply test: drifted.
- A soft knee, or a voltage that creeps on the supply test: leaky.
- On the board
- this is a first look only: the meter reads every path between those pins, and a short can be a neighbour. Lift one leg before you condemn it.
- Compare:
- If an identical part sits elsewhere on the board, measure it the same way: that is what this one should read.
- Watch for:
- A meter's diode range stops at about 2 to 3 V, so almost every Zener reads open in reverse on it, good or bad; a 3 V meter may just show a 2.4 or 2.7 V part. Above about 3 V the meter cannot tell a Zener from a plain diode.
A dead part still carries its marking. A short or an open says it has failed, not that it is a different part.
3 more parts are printed with a code easy to misread as Z20B
Printed with a code easy to misread
One character differs, and it is one that is easy to confuse under a lamp. The odd one out is marked on each.
CD214B-B220printed 220BSMBSchottky diode, 2 pins, BournsSchottky diodeSMB2 pinsBourns
Printed 220B on the part. Easy to misread as Z20B. Check that character with a loupe before you order anything.
- What it is
- Schottky diode
- Maker
- Bourns
- Package
- SMB
- Pins
- 2
- Details
- Diode: SBR, 20V, 2A, Vf<0.5V(2A), <200pF
- Source
- Published code list
Is it dead?
Diode range, part lifted or one leg off the pad. Red probe on the anode.
Working, it reads
About 0.15 to 0.45 V anode to cathode, roughly half a silicon diode, and open the other way.
Dead, it reads
- The same reading both ways round, near 0 V with a continuous beep or the same middling value: shorted.
- A reading the wrong way round as well: leaky.
- Open both ways: failed open.
- On the board
- this is a first look only: the meter reads every path between those pins, and a short can be a neighbour. Lift one leg before you condemn it.
- Compare:
- If an identical part sits elsewhere on the board, measure it the same way: that is what this one should read.
- Watch for:
- A large Schottky can read about 0.1 V forward and beep like a short, and leaks a little the wrong way when good, more when warm. It is shorted only if it reads the same both ways. Measure it cold, beside an identical cold one.
A dead part still carries its marking. A short or an open says it has failed, not that it is a different part.
TSP220SBprinted 220BSMB2 pins, PanjitNot recordedSMB2 pinsPanjit
Printed 220B on the part. Easy to misread as Z20B. Check that character with a loupe before you order anything.
- What it is
- Not recorded
- Maker
- Panjit
- Package
- SMB
- Pins
- 2
- Details
- Thy-SPD: V Of-St=220V, 80A(1ms), Bidirectional
- Source
- Published code list
Is it dead?
Diode range and ohms range, part lifted.
Working, it reads
Depends on what it is. The datasheet, or an identical part, says.
Dead, it reads
- Between two pins, the same reading both ways, near 0 V with a continuous beep: shorted.
- Open between every pair of pins: failed open, or a part that reads open when working.
- On the board
- this is a first look only: the meter reads every path between those pins, and a short can be a neighbour. Lift one leg before you condemn it.
- Compare:
- If an identical part sits elsewhere on the board, measure it the same way: that is what this one should read.
A dead part still carries its marking. A short or an open says it has failed, not that it is a different part.
1 more part has no package on record
TPS562208DDCprinted 2208DC-DC converter, 6 pins, Texas InstrumentsDC-DC converterNot recorded6 pinsTexas Instruments
Printed 2208 on the part. Easy to misread as Z20B. Check that character with a loupe before you order anything.
- What it is
- DC-DC converter
- Maker
- Texas Instruments
- Package
- Not recorded
- Pins
- 6
- Details
- 4.5V to 17V Input, 2A Synchronous Step-Down Voltage Regulator in SOT-23
- Source
- Manufacturer 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.
13 more parts have codes that begin with Z20B
Codes that begin with Z20B
For a marking with its end worn or burnt off. Each one shows its full printed code.
SGM2208XTDF12Gprinted 2208DFDFNLDO regulator, 12 pins, SG MicroLDO regulatorDFN12 pinsSG Micro
Printed 2208DF. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
- What it is
- LDO regulator
- Maker
- SG Micro
- Package
- DFN
- Pins
- 12
- Details
- 3A, Low Noise, Adjustable Output with Single Resistor and Low Dropout Regulator
- Source
- Manufacturer datasheet
Is it dead?
Voltage, board powered, black probe on ground. Then ohms with the power off.
Working, it reads
Input pin at the supply, output pin at its rated voltage, and the enable pin high if it has one.
Dead, it reads
- Output equal to the input: the pass element has shorted. Everything after it may have taken the full input.
- Input present, enable high, no output: failed open, or holding itself off into a shorted load. Power off and measure output to ground.
- Power off, input to output near 0 Ω: shorted.
- On the board:
- An output at 0 V is often a shorted load with the regulator in current limit. Lift the output pin: if the short stays on the board, the regulator may be fine.
- Compare:
- The same regulator on another rail or another board shows the right voltages and the right resistances.
- Watch for:
- Makers put input, output and ground on different pins in the same package, so take them from this part's datasheet. Diode or ohms readings between its pins say little; check it powered.
A dead part still carries its marking. A short or an open says it has failed, not that it is a different part.
BL8509-220BCRMprinted 220BCSOT-23Voltage supervisor, 3 pins, Shanghai BellingVoltage supervisorSOT-233 pinsShanghai Belling
Printed 220BC. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
- What it is
- Voltage supervisor
- Maker
- Shanghai Belling
- Package
- SOT-23
- Pins
- 3
- Details
- Voltage detector IC: 2.2V±2%, -Reset PPO, Rdt=100ms
- Source
- Published code list
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.
BL8509-220BCRNprinted 220BCSOT-23-5Voltage supervisor, 5 pins, Shanghai BellingVoltage supervisorSOT-23-55 pinsShanghai Belling
Printed 220BC. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
- What it is
- Voltage supervisor
- Maker
- Shanghai Belling
- Package
- SOT-23-5
- Pins
- 5
- Details
- Voltage detector IC: 2.2V±2%, -Reset PPO, Rdt=100ms
- Source
- Published code list
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.
BL8509-220BNRMprinted 220BNSOT-23Voltage supervisor, 3 pins, Shanghai BellingVoltage supervisorSOT-233 pinsShanghai Belling
Printed 220BN. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
- What it is
- Voltage supervisor
- Maker
- Shanghai Belling
- Package
- SOT-23
- Pins
- 3
- Details
- Voltage detector IC: 2.2V±2%, -Reset ODO, Rdt=100ms
- Source
- Published code list
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.
BL8509-220BNRNprinted 220BNSOT-23-5Voltage supervisor, 5 pins, Shanghai BellingVoltage supervisorSOT-23-55 pinsShanghai Belling
Printed 220BN. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
- What it is
- Voltage supervisor
- Maker
- Shanghai Belling
- Package
- SOT-23-5
- Pins
- 5
- Details
- Voltage detector IC: 2.2V±2%, -Reset ODO, Rdt=100ms
- Source
- Published code list
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.
GM8509B-220BCRMprinted 220BCSOT-23Voltage supervisor, 3 pins, Hangzhou Jiemao MicroelectronicsVoltage supervisorSOT-233 pinsHangzhou Jiemao Microelectronics
Printed 220BC. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
- What it is
- Voltage supervisor
- Maker
- Hangzhou Jiemao Microelectronics
- Package
- SOT-23
- Pins
- 3
- Details
- Voltage detector IC: 2.2V±2%, -Reset PPO, Rdt=100ms
- Source
- Published code list
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.
GM8509B-220BCRNprinted 220BCSOT-23-5Voltage supervisor, 5 pins, Hangzhou Jiemao MicroelectronicsVoltage supervisorSOT-23-55 pinsHangzhou Jiemao Microelectronics
Printed 220BC. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
- What it is
- Voltage supervisor
- Maker
- Hangzhou Jiemao Microelectronics
- Package
- SOT-23-5
- Pins
- 5
- Details
- Voltage detector IC: 2.2V±2%, -Reset PPO, Rdt=100ms, Td-Disable
- Source
- Published code list
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.
GM8509B-220BNRMprinted 220BNSOT-23Voltage supervisor, 3 pins, Hangzhou Jiemao MicroelectronicsVoltage supervisorSOT-233 pinsHangzhou Jiemao Microelectronics
Printed 220BN. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
- What it is
- Voltage supervisor
- Maker
- Hangzhou Jiemao Microelectronics
- Package
- SOT-23
- Pins
- 3
- Details
- Voltage detector IC: 2.2V±2%, -Reset ODO, Rdt=100ms
- Source
- Published code list
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.
GM8509B-220BNRNprinted 220BNSOT-23-5Voltage supervisor, 5 pins, Hangzhou Jiemao MicroelectronicsVoltage supervisorSOT-23-55 pinsHangzhou Jiemao Microelectronics
Printed 220BN. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
- What it is
- Voltage supervisor
- Maker
- Hangzhou Jiemao Microelectronics
- Package
- SOT-23-5
- Pins
- 5
- Details
- Voltage detector IC: 2.2V±2%, -Reset ODO, Rdt=100ms, Td-Disable
- Source
- Published code list
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.
LC9009CB3TR220BCprinted 220BCSOT-23Voltage supervisor, 3 pins, Shanghai LeadChip MicroelectronicsVoltage supervisorSOT-233 pinsShanghai LeadChip Microelectronics
Printed 220BC. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
- What it is
- Voltage supervisor
- Maker
- Shanghai LeadChip Microelectronics
- Package
- SOT-23
- Pins
- 3
- Details
- Voltage detector IC: 2.2V±2%, -Reset PPO, Rdt=100ms
- Source
- Published code list
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.
LC9009CB3TR220BNprinted 220BNSOT-23Voltage supervisor, 3 pins, Shanghai LeadChip MicroelectronicsVoltage supervisorSOT-233 pinsShanghai LeadChip Microelectronics
Printed 220BN. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
- What it is
- Voltage supervisor
- Maker
- Shanghai LeadChip Microelectronics
- Package
- SOT-23
- Pins
- 3
- Details
- Voltage detector IC: 2.2V±2%, -Reset ODO, Rdt=100ms
- Source
- Published code list
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.
LC9009CB5TR220BCprinted 220BCSOT-23-5Voltage supervisor, 5 pins, Shanghai LeadChip MicroelectronicsVoltage supervisorSOT-23-55 pinsShanghai LeadChip Microelectronics
Printed 220BC. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
- What it is
- Voltage supervisor
- Maker
- Shanghai LeadChip Microelectronics
- Package
- SOT-23-5
- Pins
- 5
- Details
- Voltage detector IC: 2.2V±2%, -Reset PPO, Rdt=100ms
- Source
- Published code list
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.
LC9009CB5TR220BNprinted 220BNSOT-23-5Voltage supervisor, 5 pins, Shanghai LeadChip MicroelectronicsVoltage supervisorSOT-23-55 pinsShanghai LeadChip Microelectronics
Printed 220BN. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
- What it is
- Voltage supervisor
- Maker
- Shanghai LeadChip Microelectronics
- Package
- SOT-23-5
- Pins
- 5
- Details
- Voltage detector IC: 2.2V±2%, -Reset ODO, Rdt=100ms
- Source
- Published code list
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.
Did you find your part?
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One code, several parts
Marking codes are not unique. In the standard code book, 6H on a SOT-23 is an NPN transistor, a varicap, an N-channel JFET, two digital transistors, a 3.6 V voltage detector: six parts from five makers. So a search on WhatSMD (What SMD) shows the parts we hold under that code and under codes easily misread as it, with only the columns that tell them apart.
- NPN transistor
- Varicap
- N-channel JFET
- Digital transistor ×2
- 3.6 V voltage detector
When more than one is left
Tap Help me choose. Up to 4 quick answers: whether the part has failed, then what separates the parts left. Those get ranked with the reasoning and a test that settles it. That uses one identification: 2 a month are free without an account, and 3 with a free account.
When you cannot read it
Tap the camera in the field. We read the characters, keep the ones we are unsure of, and search every reading. A photo too soft to read is turned back on your phone first; if it is the only one you can get, you can still send it.
Get the app
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