My Inquiry
My Account
onsemi MMBTA55LT1
- Part No.:
- MMBTA55LT1
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- -
- Datasheet:
-
MMBTA55LT1.pdf
- Description:
- TRANS DRIVER SS PNP 60V SOT23
- Quantity:
- Payment:
- Shipping:
Inventory:7,275
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
MMBTA55LT1 from onsemi is a PNP silicon small-signal transistor in SOT-23 package, rated for −60 V VCEO, −500 mA IC, and 225 mW power dissipation at 25°C. It delivers hFE ≥ 100 at −10 mA IC, VCE(sat) ≤ −0.25 V at −100 mA/−10 mA drive, and fT = 50 MHz - used in low-power switching and linear amplification stages of portable power management and signal conditioning circuits.
For engineers reviewing the MMBTA55LT1 datasheet, pinout, applications, or equivalent options, key selection criteria include verified PNP polarity, SOT-23 footprint compatibility, −60 V breakdown margin, DC current gain stability across −55°C to +150°C, and Pb-free packaging compliance per J-STD-020.
Technical Context
The MMBTA55LT1 operates as a discrete PNP bipolar junction transistor with fixed emitter-base and collector-emitter junctions optimized for medium-speed switching (tr/tf < 3 ns) and analog amplification. Its thermal resistance RJA = 556°C/W on FR-5 board enables stable operation up to +150°C junction temperature under defined derating.
Electrical behavior is characterized at TA = 25°C with validated min/max values: V(BR)CEO = −60 V (IC = −1.0 mA), ICBO ≤ −0.1 A, and VBE(on) ≤ −1.2 V at −100 mA collector current - confirming suitability for biasing, level-shifting, and active-load configurations in compact DC-DC feedback paths.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | −60 V - Maximum safe collector-emitter voltage before avalanche breakdown; sets upper rail limit in negative-rail switch or level-shift stage. |
| IC | −500 mA - Continuous collector current rating; supports load switching up to ~450 mA with thermal margin on standard PCB. |
| PD | 225 mW @ 25°C - Total device dissipation on FR-5 board; requires 1.8 mW/°C derating above ambient for sustained operation. |
| hFE | ≥100 @ −10 mA, −1.0 V - DC current gain sufficient for single-stage amplification or saturated switching with modest base drive. |
| fT | 50 MHz - Current-gain bandwidth product; enables use in audio-frequency amplifiers and sub-10 MHz digital signal routing. |
| VCE(sat) | ≤ −0.25 V @ −100 mA/−10 mA - Low saturation voltage minimizes conduction loss in high-efficiency PNP switch applications. |
Pinout & Package
SOT-23 (Case 318, Style 6) surface-mount package with 3-pin configuration: 1.00 mm height, 2.90 mm length, 1.30 mm width, and 0.95 mm lead pitch - compatible with standard 0.65 mm pitch reflow footprints.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Base | Control terminal for forward-biased PNP operation; requires negative bias relative to emitter to enable conduction. |
| 2 | Emitter | Current source terminal; connected to higher potential rail in common-emitter switch or amplifier configurations. |
| 3 | Collector | Current sink terminal; tied to load or lower-potential node; reverse polarity vs NPN devices dictates layout orientation. |
Key Features
| Feature | Design Value |
|---|---|
| Pb-free SOT-23 package | Complies with RoHS Directive 2011/65/EU and J-STD-020 moisture sensitivity level 1 (MSL1) for unlimited floor life. |
| −60 V VCEO rating | Supports operation in −48 V telecom systems, industrial −24 V rails, and automotive battery-referenced logic interfaces. |
| hFE ≥ 100 at −10 mA | Enables reliable base drive design with minimal current sourcing requirement from microcontroller GPIO or op-amp outputs. |
| VCE(sat) ≤ −0.25 V | Reduces power loss to < 25 mW at 100 mA load, critical for thermally constrained portable and IoT node designs. |
Applications
| Industrial Power Sequencing | Automotive Body Control Module |
|---|---|
|
Use Scenario: Controlling 12 V accessory power enable/disable during ignition cycle sequencing. IC Role / Device Role / Timing Role: PNP high-side switch driving relay coil or MOSFET gate with inverted logic control from MCU. Use Value: −60 V VCEO withstands load-dump transients; SOT-23 footprint saves space in dense BCM PCB layouts. |
Use Scenario: Level-shifting CAN transceiver standby control signals between 3.3 V MCU and 5 V bus interface. IC Role / Device Role / Timing Role: Inverting level translator with rail-to-rail input swing and fast turn-off (< 3 ns). Use Value: fT = 50 MHz ensures clean edge integrity; −0.25 V VCE(sat) maintains low-voltage logic compatibility. |
| Portable Medical Sensor Biasing | Consumer Audio Signal Amplification |
|
Use Scenario: Providing stable bias current to low-noise op-amp input stages in battery-powered ECG front-ends. IC Role / Device Role / Timing Role: Constant-current source configured in emitter-follower topology with precision resistor setpoint. Use Value: hFE ≥ 100 ensures predictable current mirror ratio; −55°C to +150°C TJ range covers clinical operating environments. |
Use Scenario: Single-ended preamplifier stage for MEMS microphone output in Bluetooth earbuds. IC Role / Device Role / Timing Role: Common-emitter small-signal amplifier with gain set by collector resistor and hFE. Use Value: 50 MHz fT supports full 20 Hz–20 kHz audio bandwidth with flat response; SOT-23 enables miniaturized acoustic module design. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar PNP small-signal transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MMBTA56LT1 | Higher −80 V VCEO and same SOT-23 package; otherwise identical pinout, hFE, and fT. | Preferred for systems requiring extended overvoltage margin beyond −60 V, e.g., 48 V industrial controls. | Select MMBTA56LT1 when design must survive >−60 V transients without redesign; no layout change needed. |
| BC807-40LT1G | Same −45 V VCEO, but hFE = 250–630 (higher gain spread); Pb-free SOT-23, identical pinout. | Better suited for high-gain linear amplification where tighter hFE tolerance is not required. | Choose BC807-40LT1G only if system benefits from higher nominal hFE; verify saturation voltage meets target VCE(sat) spec. |
Compared with MMBTA55LT1, MMBTA56LT1 offers higher voltage robustness with identical form-factor and drive requirements, while BC807-40LT1G trades guaranteed −60 V rating for wider hFE range - making MMBTA55LT1 optimal for cost-sensitive, voltage-critical PNP switching where consistent −60 V margin and predictable gain are mandatory.
Availability
MMBTA55LT1 is available at Aetrix Electronics and suitable for industrial power sequencing, automotive body control modules, portable medical sensor biasing, and consumer audio signal amplification requiring stable component supply and long-term obsolescence management.
Supply support for MMBTA55LT1 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
onsemi (formerly ON Semiconductor) is a global semiconductor supplier focused on energy-efficient electronics, delivering silicon solutions for automotive, industrial, cloud, and intelligent edge applications.
The MMBTA55LT1 belongs to onsemi's legacy small-signal transistor family designed for general-purpose PNP switching and amplification in space-constrained, cost-sensitive applications - emphasizing reliability, Pb-free compliance, and broad temperature operation.
FAQ
What is the maximum junction temperature specification for the MMBTA55LT1?
The MMBTA55LT1 has a specified junction and storage temperature range of −55°C to +150°C. This allows operation in harsh environments such as under-hood automotive locations or industrial enclosures without derating, provided PCB thermal design maintains junction temperature within this limit using the published RJA = 556°C/W value.
Is the MMBTA55LT1 pin-compatible with the MMBTA56LT1?
Yes, the MMBTA55LT1 is pin-compatible with the MMBTA56LT1 - both use identical SOT-23 (Case 318, Style 6) packaging and share the same pin 1 (Base), pin 2 (Emitter), pin 3 (Collector) assignment. This enables direct substitution where −80 V VCEO margin is acceptable or desired.
Does the MMBTA55LT1 meet RoHS requirements?
Yes, the MMBTA55LT1 is offered in Pb-free versions (e.g., MMBTA55LT1G) compliant with the EU RoHS Directive 2011/65/EU. The standard MMBTA55LT1 is also RoHS-compliant per onsemi's documentation, with lead finish meeting JEDEC J-STD-020 MSL1 classification for moisture sensitivity.
What is the typical VBE(on) for the MMBTA55LT1 at −100 mA collector current?
The MMBTA55LT1 exhibits VBE(on) ≤ −1.2 V at −100 mA collector current and −1.0 V VCE, per its Electrical Characteristics table. This value reflects forward-bias voltage drop under moderate drive conditions and informs base resistor sizing in switching applications.
Can the MMBTA55LT1 be used in linear amplifier configurations?
Yes, the MMBTA55LT1 supports linear operation with hFE ≥ 100 at −10 mA and fT = 50 MHz, enabling use in low-noise, low-power audio preamplifiers or sensor signal conditioning stages - provided biasing keeps VCE > VCE(sat) and power dissipation remains within 225 mW derated limits.
MMBTA55LT1 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- *
- Package/Case:
- -
- Packaging:
- Cut Tape (CT)
- Product Status:
- Obsolete
- Transistor Type:
- -
- Current - Collector (Ic) (Max):
- -
- Voltage - Collector Emitter Breakdown (Max):
- -
- Vce Saturation (Max) @ Ib, Ic:
- -
- Current - Collector Cutoff (Max):
- -
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- -
- Power - Max:
- -
- Frequency - Transition:
- -
- Operating Temperature:
- -
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- -
- Supplier Device Package:
- -
MMBTA55LT1 FAQ
1.How can I place an order for MMBTA55LT1 through Aetrix?
Please submit a Request for Quotation (RFQ) for MMBTA55LT1 on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for MMBTA55LT1 reliable?
The price and inventory of MMBTA55LT1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MMBTA55LT1 is usually 5 days.
3.What payment methods are accepted for MMBTA55LT1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MMBTA55LT1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MMBTA55LT1?
MMBTA55LT1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MMBTA55LT1 order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for MMBTA55LT1?
For technical support, including MMBTA55LT1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MMBTA55LT1 requirements.
6.How does Aetrix verify that MMBTA55LT1 is sourced from the original manufacturer or authorized distributors?
All MMBTA55LT1 products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that MMBTA55LT1 meets industry standards.
7.What is the process for return or replacement of MMBTA55LT1?
All MMBTA55LT1 units undergo pre-shipment inspection (PSI). If there is an issue with MMBTA55LT1, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The MMBTA55LT1 part is unused and in its original packaging.
Return procedure for MMBTA55LT1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MMBTA55LT1 Tags
-
MMBT3906LT1G
onsemi
-
MMBT3904-7-F
Diodes Incorporated
-
MMBT3904LT1G
onsemi
-
MMBT3906-7-F
Diodes Incorporated
-
MMBT3904-TP
Micro Commercial Co
-
MMBT2222A-7-F
Diodes Incorporated
-
BC846BLT1G
onsemi
-
BC847B,215
Nexperia USA Inc.
-
SMMBT3904LT1G
onsemi
-
MMBT2222A-TP
Micro Commercial Co
-
MMBTA06LT1G
onsemi
-
MMBT2222ALT1G
onsemi
Tech Hub
Counterfeit components can hide behind convincing markings and passing basic function tests. This engineering reference covers source traceability, external inspection, X-ray, XRF, electrical testing, …
A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
