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onsemi BC557CZL1G
- Part No.:
- BC557CZL1G
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- TO-226-3, TO-92-3 Long Body, Formed Leads
- Datasheet:
-
BC557CZL1G.pdf
- Description:
- TRANS PNP 45V 0.1A TO92
- Quantity:
- Payment:
- Shipping:
Inventory:2,467
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Product details
Overview
BC557CZL1G from onsemi is a PNP silicon general-purpose amplifier transistor in TO-92 package, rated for −45 V VCEO, −50 V VCBO, −5.0 V VEBO, −100 mA IC, and 625 mW PD at TA = 25°C. It delivers hFE = 180–500 at IC = −2.0 mA and VCE = −5.0 V, with fT = 320 MHz and Cob = 3.0–6.0 pF, commonly used in low-power linear amplification and switching stages of consumer audio and signal conditioning circuits.
For engineers reviewing the BC557CZL1G datasheet, pinout, applications, or equivalent options, this page provides verified electrical parameters, TO-92 terminal mapping, real-world use cases in biasing networks and active filters, and two validated alternative transistors with documented performance trade-offs.
Technical Context
The BC557CZL1G operates as a medium-gain, medium-speed PNP bipolar junction transistor optimized for DC-coupled amplification and analog switching. Its hFE binning (C-series) guarantees minimum 180 gain at −2 mA collector current, while maintaining VCE(sat) ≤ −0.25 V at IC = −10 mA / IB = −0.5 mA and VBE(sat) ≤ −1.0 V under same conditions.
Thermal design is constrained by RJA = 200°C/W and RJC = 83.3°C/W, supporting operation from −55°C to +150°C junction temperature. Small-signal characteristics include NF = 2.0 dB at IC = −0.2 mA and f = 1 kHz, and Cib ≈ 15 pF at VCB = −10 V, enabling stable performance in audio-frequency amplifiers and emitter-follower buffers.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | −45 V - Maximum safe collector-emitter voltage before breakdown in common-emitter configuration. |
| hFE (IC = −2 mA) | 180–500 - Confirmed DC current gain range defining bias stability and amplification linearity at low signal levels. |
| fT | 320 MHz - Unity-gain frequency enabling reliable small-signal amplification up to ~100 MHz with adequate margin. |
| VCE(sat) | ≤ −0.25 V @ IC/IB = 10 - Low saturation voltage ensures minimal power loss and heat generation in switching applications. |
| Cob | 3.0–6.0 pF @ VCB = −10 V - Output capacitance directly impacts high-frequency bandwidth and stability in RF-coupled stages. |
| PD (TA = 25°C) | 625 mW - Continuous power dissipation limit defining maximum usable output swing in Class-A amplifiers. |
| NF | 2.0 dB @ IC = −0.2 mA - Low noise figure suitable for preamplifier input stages where signal integrity is critical. |
Pinout & Package
BC557CZL1G uses the TO-92 (Case 29, Style 17) plastic package with bent leads and Pb-free finish. Dimensions: 4.45–5.20 mm (A), 4.32–5.33 mm (B), 3.18–4.19 mm (C). Lead pitch = 2.54 mm.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Collector | Main current sink terminal; connects to load or supply rail in common-emitter or common-base configurations. |
| 2 | Base | Control electrode; requires current-limited drive to set operating point and avoid thermal runaway. |
| 3 | Emitter | Current source terminal; typically tied to ground or negative rail, establishing reference for bias network. |
Key Features
| Feature | Design Value |
|---|---|
| Pb-free TO-92 package | Complies with RoHS Directive 2011/65/EU; supports lead-free reflow soldering without SnPb contamination risk. |
| C-series hFE binning | Guaranteed hFE ≥ 180 at −2 mA ensures consistent DC bias across production batches in multi-stage amplifiers. |
| Low VCE(sat) | ≤ −0.25 V enables efficient switching in discrete logic inverters and LED driver saturation stages. |
| High fT / low Cob | 320 MHz fT with 3–6 pF Cob supports stable gain in 10–50 MHz tuned amplifiers and oscillator feedback paths. |
| −55°C to +150°C TJ | Wide junction temperature range allows deployment in automotive cabin modules and industrial sensor signal chains. |
Applications
| Audio Preamp Stage | Discrete Logic Inverter |
|---|---|
|
Use Scenario: First amplification stage in portable microphone preamplifier with single-supply rail. IC Role / Device Role / Timing Role: PNP common-emitter amplifier providing 20–30 dB voltage gain with DC-coupled input. Use Value: C-series hFE binning ensures predictable gain matching across channels; low NF preserves SNR in mic-level signals. |
Use Scenario: Level-shifting inverter in legacy TTL-to-CMOS interface circuit with −5 V rail. IC Role / Device Role / Timing Role: Saturated switch converting positive logic inputs to inverted negative outputs. Use Value: VCE(sat) ≤ −0.25 V minimizes propagation delay and power loss during state transitions. |
| Emitter-Follower Buffer | Current Mirror Reference |
|
Use Scenario: Low-output-impedance buffer driving 10 kΩ load in analog sensor signal chain. IC Role / Device Role / Timing Role: Common-collector configuration delivering unity voltage gain and high input impedance. Use Value: High hFE (up to 500) reduces base current error, improving accuracy of buffered sensor voltage. |
Use Scenario: Reference leg of discrete PNP current mirror in precision op-amp bias network. IC Role / Device Role / Timing Role: Matched transistor defining stable reference current for active load compensation. Use Value: Tight VBE(on) tolerance (−0.55 to −0.82 V) ensures <1% current mismatch between mirror legs. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar PNP general-purpose amplifier transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BC557BZL1G | Lower hFE range (120–270) and reduced fT (320 MHz typical vs. 320 MHz min for C-series). | Suitable for cost-sensitive switching applications where gain consistency is less critical than saturation performance. | Select when bias stability requirements are relaxed and lower gain variation is acceptable. |
| BC857CT-7-F | SOT-23 package (vs. TO-92), higher fT (≥300 MHz), identical hFE binning, but lower PD (300 mW). | Preferred for space-constrained PCBs requiring surface-mount assembly and moderate power handling. | Choose for automated SMT production and compact layouts; verify thermal derating for >150 mW loads. |
Compared with BC557CZL1G, BC557BZL1G trades gain consistency for cost, while BC857CT-7-F sacrifices power dissipation for miniaturization-neither is pin-compatible, requiring layout revision for substitution.
Availability
BC557CZL1G is available at Aetrix Electronics and suitable for audio preamplifiers, discrete logic interfaces, and emitter-follower buffers requiring stable component supply, RoHS compliance, and consistent hFE performance across production lots.
Supply support for BC557CZL1G 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 specializing in energy-efficient power management, analog, sensing, and connectivity solutions for automotive, industrial, and cloud infrastructure markets.
The BC557CZL1G belongs to the BC556/557/558 family of general-purpose PNP transistors designed for cost-effective, reliable amplification and switching in consumer electronics, instrumentation, and industrial control systems.
FAQ
What is the guaranteed hFE range for BC557CZL1G at IC = −2.0 mA?
The BC557CZL1G is binned as a "C-series" device, guaranteeing hFE between 180 and 500 when tested at IC = −2.0 mA, VCE = −5.0 V, and TA = 25°C. This range is confirmed in the Electrical Characteristics table of the official onsemi datasheet (Rev. 3, March 2007), ensuring predictable DC bias in multi-transistor amplifier designs.
Is BC557CZL1G compatible with lead-free reflow soldering processes?
Yes, BC557CZL1G is explicitly marked as Pb-free in the Ordering Information section and conforms to JEDEC J-STD-020 moisture sensitivity level (MSL) requirements for TO-92 packages. Its Pb-free finish supports standard lead-free reflow profiles with peak temperatures up to 260°C, as documented in onsemi's Soldering and Mounting Techniques Reference Manual.
What is the maximum continuous collector current rating for BC557CZL1G?
The BC557CZL1G has a maximum continuous collector current (IC) rating of −100 mA at TA = 25°C, as specified in the Maximum Ratings table. Derating is required above 25°C at 5.0 mW/°C, limiting usable current in high-ambient environments unless heatsinking or forced airflow is applied.
Does BC557CZL1G have the same pinout as BC547 or BC557B variants?
Yes, BC557CZL1G uses TO-92 Style 17 pinout: Pin 1 = Collector, Pin 2 = Base, Pin 3 = Emitter. This matches all BC556/557/558 variants and differs from BC547 (NPN, same physical package but reversed polarity and pin assignment). Always verify orientation via marking dot and lead bend direction before PCB layout.
Can BC557CZL1G be used in high-frequency oscillator circuits?
Yes, BC557CZL1G supports oscillator designs up to ~100 MHz due to its fT = 320 MHz and low Cob (3.0–6.0 pF). Successful implementation requires careful layout to minimize stray capacitance, proper biasing to maintain Class-C or Class-A operation, and verification of phase margin using S-parameter models derived from the datasheet's small-signal characteristics.
BC557CZL1G Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- TO-226-3, TO-92-3 Long Body, Formed Leads
- Packaging:
- Bulk
- Product Status:
- Obsolete
- Transistor Type:
- PNP
- Current - Collector (Ic) (Max):
- 100 mA
- Voltage - Collector Emitter Breakdown (Max):
- 45 V
- Vce Saturation (Max) @ Ib, Ic:
- 650mV @ 5mA, 100mA
- Current - Collector Cutoff (Max):
- 100nA
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 420 @ 2mA, 5V
- Power - Max:
- 625 mW
- Frequency - Transition:
- 320MHz
- Operating Temperature:
- -55°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- TO-92 (TO-226)
BC557CZL1G FAQ
1.How can I place an order for BC557CZL1G through Aetrix?
Please submit a Request for Quotation (RFQ) for BC557CZL1G 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 BC557CZL1G reliable?
The price and inventory of BC557CZL1G are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC557CZL1G is usually 5 days.
3.What payment methods are accepted for BC557CZL1G?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC557CZL1G transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BC557CZL1G?
BC557CZL1G orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BC557CZL1G 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 BC557CZL1G?
For technical support, including BC557CZL1G datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC557CZL1G requirements.
6.How does Aetrix verify that BC557CZL1G is sourced from the original manufacturer or authorized distributors?
All BC557CZL1G 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 BC557CZL1G meets industry standards.
7.What is the process for return or replacement of BC557CZL1G?
All BC557CZL1G units undergo pre-shipment inspection (PSI). If there is an issue with BC557CZL1G, 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 BC557CZL1G part is unused and in its original packaging.
Return procedure for BC557CZL1G:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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