NST857AMX2T5G Equivalent & Substitute Parts

Part Overview

The NST857AMX2T5G is an active-status PNP bipolar junction transistor manufactured by onsemi, designed for surface mount applications in the 3-X2DFN (1x0.6) package. This component operates at maximum collector currents of 100 mA with a collector-emitter breakdown voltage of 45 V and a maximum power dissipation of 225 mW. The device is specified for operating temperatures ranging from -55°C to 150°C and features a transition frequency of 100 MHz. Identification of equivalent and substitute parts is necessary to support design flexibility, supply chain continuity, and component availability across manufacturing cycles.

Substiute Parts

NST857AMX2T5G

onsemiIn Stock: 9164NST857AMX2T5G Datasheet

Current PartRFQ

NST857AMX2T5G

onsemiIn Stock: 9164NST857AMX2T5G Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the NST857AMX2T5G is determined by strict equivalence across the following critical parameters:

Transistor Type: PNP topology is mandatory; NPN devices are not interchangeable.

Electrical Ratings: Substitute parts must meet or exceed the maximum collector current (100 mA), collector-emitter breakdown voltage (45 V), and power dissipation (225 mW) specifications.

Saturation Characteristics: Vce saturation at specified bias conditions (650 mV @ 5 mA, 100 mA) establishes switching performance requirements.

Frequency Response: Transition frequency of 100 MHz defines high-frequency performance capability.

Package Compatibility: The 3-X2DFN (1x0.6) surface mount package is a critical mechanical constraint for PCB layout and assembly processes.

Compliance Requirements: RoHS3 compliance and MSL Level 1 rating are mandatory for supply chain and manufacturing compatibility.

Product Status: Only active-status components are listed as substitutes to ensure long-term availability and support.

Parameter Comparison

Engineering Selection Recommendations

The NST857AMX2T5G maintains active product status with full RoHS3 compliance and MSL Level 1 rating, ensuring compatibility with current manufacturing and environmental standards. The part is available in production quantities (9118 pcs in stock) and is suitable for immediate integration into designs requiring PNP transistor functionality within the specified electrical and thermal parameters.

When selecting this component or its equivalents, confirm that the application circuit design accommodates the specified saturation voltage (650 mV), collector current limits (100 mA maximum), and operating temperature range (-55°C to 150°C). The 3-X2DFN package footprint must be verified against PCB layout constraints and assembly equipment capabilities. Compliance certifications (RoHS3, REACH Unaffected, EAR99) are maintained across all equivalent parts listed.

Frequently Asked Questions (FAQ)

Q: What defines a valid substitute for the NST857AMX2T5G?

A: A valid substitute must be a PNP bipolar junction transistor with identical or superior electrical ratings (100 mA collector current, 45 V breakdown voltage, 225 mW power dissipation), matching saturation characteristics (650 mV @ 5 mA, 100 mA), equivalent transition frequency (100 MHz), and the same 3-X2DFN (1x0.6) surface mount package. The substitute must maintain active product status and RoHS3 compliance.

Q: Can NPN transistors replace the NST857AMX2T5G?

A: No. The NST857AMX2T5G is a PNP device. NPN transistors have opposite polarity and cannot be substituted without complete circuit redesign. Polarity mismatch will result in circuit malfunction.

Q: Is the 3-X2DFN package interchangeable with other surface mount packages?

A: No. The 3-X2DFN (1x0.6) package is a specific form factor with defined footprint, pin spacing, and height. PCB layouts and assembly processes are designed for this exact package. Alternative packages require PCB redesign and revalidation.

Q: What is the significance of the 100 MHz transition frequency specification?

A: The transition frequency (fT) of 100 MHz defines the maximum frequency at which the transistor can amplify signals. Applications requiring higher-frequency operation must use devices with higher fT ratings. Lower-frequency applications can use this device without limitation.

Q: Does the MSL Level 1 rating affect component handling?

A: MSL Level 1 (Unlimited) indicates the component has unlimited shelf life and does not require moisture-controlled storage or baking procedures prior to assembly. Standard handling and storage practices are sufficient.

Q: Are there any restrictions on the operating temperature range?

A: The NST857AMX2T5G is specified for operation from -55°C to 150°C junction temperature. Applications must ensure that thermal management and circuit design maintain the transistor junction temperature within this range under all operating conditions.

Q: What compliance certifications apply to this component?

A: The NST857AMX2T5G is RoHS3 compliant, REACH unaffected, and classified under ECCN EAR99. These certifications confirm environmental and export compliance for standard commercial applications.