AB - SOT-23 Marking Code | MMBZ5226B Zener Diode | Semtech
N.º da peça: AB ✓ Ativo| Qtd. | Preço unitário | Total |
|---|---|---|
| 1 | $0.18 | $0,18 |
| 10 | $0.15 | $1,50 |
| 100 | $0.1 | $10,00 |
| 500 | $0.08 | $40,00 |
| 1.000 | $0.06 | $60,00 |
AB Visão geral
A Zener diode is a specialized silicon PN-junction diode engineered to operate in reverse breakdown at a defined voltage. Within the broader semiconductor taxonomy, Zener diodes sit under discrete semiconductors -> diodes -> voltage reference diodes. They are used to clamp voltage excursions, establish stable reference rails, and protect downstream circuitry from ESD or transient over-voltage events.
Key features of the MMBZ5226B (AB marking) include a nominal Zener voltage of 3.3 V at the standard test current, low leakage current in the forward-biased region, and a SOT-23 outline that enables high-density PCB placement. The part shares its footprint with thousands of other SOT-23 devices, allowing drop-in substitution across many low-voltage regulator or reference circuits.
The architecture is a planar silicon die with controlled doping to set the breakdown voltage, then wire-bonded into the SOT-23 lead frame. The small package provides moderate thermal dissipation suitable for low-current regulator applications but limits continuous power dissipation, which must be respected in the PCB layout.
Typical applications include 3.3 V reference generation in portable electronics, voltage clamping on data lines, ESD protection for handheld devices, and bias reference in low-power analog circuits. Designers select this part when board space is constrained and a compact, well-characterized reference voltage is required.
When designing with this part, observe the maximum power dissipation rating for the SOT-23 package and ensure PCB copper pad area provides adequate heatsinking. For applications requiring tight tolerance or higher power, verify the test current and dynamic impedance in the manufacturer datasheet.
This page synthesizes distributor inventory, drop-in SOT-23 alternatives with the same footprint, and design guidance that complements the manufacturer datasheet rather than simply repeating it.
Alternativas drop-in para AB — mesmo encapsulamento, compatível pino a pino. Peças de encapsulamento diferente que exigem retrabalho na PCB são excluídas.
Ferramenta de comparação rápida — selecione peças alternativas para comparação lado a lado:
BZX84C3V3LT1G
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
BZX84-A3V3
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
BZX84C3V0LT1G
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
BZX84C3V6LT1G
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
MMBZ5226BS-7-F
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
AB Classificações máximas e características elétricas
| Marking Code | AB |
| Part Number (Marked) | MMBZ5226B |
| Manufacturer | Semtech Corporation |
| Device Type | Silicon Planar Zener Diode |
| Encapsulamento | SOT-23 (3-pin) |
| Tipo de montagem | Surface Mount |
| Nominal Zener Voltage (Vz) | 3.3 V |
| Status RoHS | unknown |
Configuração de pinos do AB
| Pino 1 | Anode 1 — Anode terminal of Zener diode (per Semtech datasheet) |
| Pino 2 | Anode 2 / NC — Second anode or no-connect depending on variant (per datasheet) |
| Pino 3 | Cathode — Cathode / common terminal (per Semtech datasheet) |
Aplicações típicas
AB é adequado para 6 aplicaçãos: 3.3 V Voltage Reference, ESD / Transient Voltage Clamping, Portable / Battery Device Bias Reference, Microcontroller Reset Supervisor辅助, LED Current Limiting / Bias, Industrial Control Panel Signal Conditioning.
3.3 V Voltage Reference
The MMBZ5226B (AB marking) is well suited as a 3.3 V shunt reference for low-power analog blocks, ADCs, and microcontroller rails. With its 3.3 V nominal Zener voltage and planar silicon process, it provides a stable reference when biased from a higher supply through a current-limiting resistor. Compared to active reference ICs the MMBZ5226B adds no quiescent current overhead but offers less initial accuracy and temperature drift, so reserve it for non-precision rails where the SOT-23 footprint and low cost are priorities.
Recomendado
ESD / Transient Voltage Clamping
The MMBZ5226B in SOT-23 can serve as a compact voltage clamp on signal lines, GPIO pins, or low-voltage data interfaces. Its 3.3 V breakdown is close to typical 3.3 V logic rails, diverting transient over-voltage away from sensitive ICs. For higher-energy transients, designers usually parallel a TVS diode such as the SMBJ series; the MMBZ5226B handles low-energy clamping where board space is constrained and the SOT-23 footprint simplifies layout.
Recomendado
Portable / Battery Device Bias Reference
In portable and battery-powered designs, the MMBZ5226B can generate a 3.3 V bias for low-current analog or sensor blocks from a single-cell Li-ion source (nominally 3.6-4.2 V). Its small SOT-23 outline suits wearables and IoT endpoints where every square millimeter matters. Designers should bias the Zener with a series resistor sized to deliver 1-5 mA and accept the typical 1-2 mA quiescent loss in exchange for a simple, inductor-free reference.
Recomendado
Microcontroller Reset Supervisor辅助
The MMBZ5226B (AB marking) can act as a simple voltage threshold element in discrete reset or power-good circuits for microcontrollers running at 3.3 V. By combining the Zener with a comparator or transistor, designers implement a low-cost brown-out detector. Compared to dedicated supervisor ICs like the TPS3823, this approach costs less but has wider threshold tolerance and slower response, so it fits cost-sensitive designs rather than safety-critical supervision.
Recomendado
LED Current Limiting / Bias
The MMBZ5226B is occasionally used to set a stable bias point for indicator LEDs or low-current optocouplers, exploiting its 3.3 V Zener voltage as a simple shunt regulator. This is a cost-effective solution when a constant-current source IC is overkill but a fixed voltage drop is needed for predictable LED brightness across supply variations. For precision LED current control, a dedicated LED driver such as the PAM8016AKR or NSI50350AST3G is preferred.
Recomendado
Industrial Control Panel Signal Conditioning
In industrial control panels, the MMBZ5226B (AB marking) provides compact 3.3 V clamping or referencing on PLC digital input modules, sensor signal conditioning boards, and HMI panels. Its SOT-23 footprint enables dense layouts inside sealed modules, while the planar silicon Zener offers adequate surge tolerance for factory-floor environments when paired with upstream series resistance. For harsher EMI/ESD environments, supplement with dedicated TVS arrays rather than relying on the MMBZ5226B alone.
Recomendado
Resumo dos produtos recomendados
Dados de referência de engenharia para AB — comparação, orientação de projeto e informações de conformidade.
Guia de seleção
Comparação com alternativas
| Parâmetro | Este produto | BZX84C3V3LT1G | BZX84-A3V3 | BZX84C3V0LT1G | BZX84C3V6LT1G | MMBZ5226BS-7-F |
|---|---|---|---|---|---|---|
| Package | SOT-23 | SOT-23 - same | SOT-23 - same | SOT-23 - same | SOT-23 - same | SOT-23 - same |
| Brand | Semtech Corporation | onsemi | Nexperia | onsemi | onsemi | Diodes Incorporated |
| Nominal Zener Voltage | 3.3 V | 3.3 V | 3.3 V | 3.0 V | 3.6 V | 3.3 V |
| Device Type | Zener Diode | Zener Diode | Zener Diode | Zener Diode | Zener Diode | Zener Diode |
| Mounting Type | Surface Mount | Surface Mount | Surface Mount | Surface Mount | Surface Mount | Surface Mount |
| Approximate Unit Price (USD, qty 1) | 0.18 | 0.12 | 0.14 | 0.12 | 0.12 | 0.15 |
| RoHS Status | unknown | compliant | compliant | compliant | compliant | compliant |
| Source | Semtech datasheet (3 pages) | onsemi datasheet | Nexperia datasheet | onsemi datasheet | onsemi datasheet | Diodes Incorporated datasheet |
Principais diferenciais
- Wide cross-vendor SOT-23 3.3 V Zener availability (vs BZX84C3V3LT1G (onsemi))
- Tighter tolerance variant available in same footprint (vs BZX84-A3V3 (Nexperia))
- Adjacent voltage variants drop-in (vs BZX84C3V0LT1G / BZX84C3V6LT1G)
Notas de projeto
Estimated: the MMBZ5226B in SOT-23 dissipates approximately 200-300 mW continuous on a standard 1 oz copper FR-4 PCB with a theta_JA around 300-400 C/W. At 200 mW the die temperature rises roughly 60-80 C above ambient. For higher dissipation, use larger copper pad area or move to a SOT-223/Zener with higher Pd rating, and re-validate Zener voltage drift at operating temperature.
Recommended: keep the Zener's anode and cathode PCB traces short and direct to minimize parasitic inductance that can defeat high-frequency clamping. Place the series bias resistor close to the Zener cathode, and provide a small local bypass capacitor (e.g. 100 nF) across the Zener if the reference feeds a high-impedance but transient-sensitive node.
Critical: do not assume the marking code 'AB' uniquely identifies the MMBZ5226B across all manufacturers - other vendors may use the same top-side marking code for different silicon. Always cross-check the manufacturer's marking lookup table and the package dimensions against your BOM before committing the part in production, especially when sourcing from multiple vendors.
Informações de conformidade
Compliance status was not present in the verified web data; consult Semtech's product compliance certificate or contact the manufacturer for current RoHS/REACH declarations.
