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onsemi BC557CZL1
- Part No.:
- BC557CZL1
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- TO-226-3, TO-92-3 Long Body, Formed Leads
- Datasheet:
-
BC557CZL1.pdf
- Description:
- TRANS PNP 45V 0.1A TO92
- Quantity:
- Payment:
- Shipping:
Inventory:6,312
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Product details
Overview
BC557CZL1 from onsemi is a PNP silicon small-signal 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, VCE = −5.0 V, and fT = 320 MHz, supporting linear amplification and switching in low-power analog circuits.
For engineers reviewing the BC557CZL1 datasheet, pinout, applications, or equivalent options, this part is selected for general-purpose PNP amplification where DC gain stability, low noise (NF = 2.0 dB), and predictable saturation behavior (VCE(sat) ≤ −0.25 V at IC = −10 mA, IB = −0.5 mA) are critical in discrete bias networks and signal conditioning stages.
Technical Context
The BC557CZL1 operates as a medium-gain, medium-speed PNP bipolar junction transistor optimized for linear amplification and active-mode switching. Its hFE binning (C-series) guarantees minimum DC current gain of 180 at IC = −2.0 mA and extends to 500 at IC = −100 mA, enabling stable biasing across temperature and load variations.
Thermal design is supported by RJA = 200°C/W and RJC = 83.3°C/W, with safe operating area validated up to −100 mA and −45 V in single-pulse conditions. The device exhibits Cob = 3.0–6.0 pF and fT = 320 MHz, confirming suitability for audio-frequency and low-MHz RF preamplifier stages.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | −45 V - Maximum collector-emitter voltage before breakdown; defines usable supply headroom in common-emitter amplifier designs. |
| hFE (IC = −2.0 mA) | 180–500 - Guaranteed DC current gain range for C-series; enables precise bias point setting without gain-dependent thermal drift compensation. |
| fT | 320 MHz - Unity-gain frequency; supports stable small-signal amplification up to ~30 MHz with adequate phase margin. |
| VCE(sat) | ≤ −0.25 V @ IC = −10 mA, IB = −0.5 mA - Low saturation voltage ensures minimal power loss and heat generation in switching applications. |
| NF | 2.0 dB @ IC = −0.2 mA, f = 1 kHz - Low noise figure confirms suitability for high-fidelity preamplifier inputs and sensor interface front-ends. |
| PD (TA = 25°C) | 625 mW - Continuous power dissipation limit; sets maximum allowable I2R + VCEIC in ambient-mounted TO-92 layouts. |
| Cob | 3.0–6.0 pF @ VCB = −10 V - Output capacitance impacts high-frequency roll-off and stability in multi-stage amplifiers. |
Pinout & Package
BC557CZL1 uses the standard TO-92 (Case 29, Style 17) through-hole plastic package with 3 leads. Lead spacing matches JEDEC TO-226 outline, enabling compatibility with legacy PCB footprints and manual soldering processes.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 - Collector | Main current sink terminal | Connected to load or supply rail in common-emitter configuration; must withstand −45 V reverse bias and −100 mA continuous current. |
| 2 - Base | Control input for minority-carrier injection | Receives forward-biased current to modulate collector current; requires series resistance to limit IB ≤ −200 mA peak per datasheet rating. |
| 3 - Emitter | Current source reference terminal | Typically tied to ground or positive rail in PNP configurations; supports −5.0 V reverse bias relative to base (VEBO). |
Key Features
| Feature | Design Value |
|---|---|
| PNP silicon BJT architecture | Enables complementary pairing with NPN devices like BC547/BC548 for push-pull output stages and differential amplifiers. |
| C-series hFE binning | Guarantees minimum hFE = 180 at low current, reducing need for gain-tolerance margins in precision bias networks. |
| Low VCE(sat) | Ensures <0.25 V drop at 10 mA collector current, minimizing voltage overhead in battery-powered emitter-follower buffers. |
| 2.0 dB noise figure | Supports clean amplification of microvolt-level signals from piezoelectric sensors or electret microphone elements. |
| TO-92 Pb-free option (ZL1G) | Meets RoHS compliance requirements without derating; identical electrical specs and thermal performance vs. leaded version. |
Applications
| Audio Preamp Stage | Discrete Voltage Regulator |
|---|---|
|
Use Scenario: Amplifying weak signals from dynamic microphones or guitar pickups before ADC or op-amp buffering. IC Role / Device Role / Timing Role: PNP small-signal amplifier in common-emitter configuration with emitter degeneration resistor. Use Value: hFE = 180–500 ensures consistent gain across units; 2.0 dB NF preserves signal integrity in first amplification stage. |
Use Scenario: Implementing adjustable linear regulator feedback loop using Zener reference and pass transistor. IC Role / Device Role / Timing Role: PNP pass transistor controlling output voltage via base current modulation from error amplifier. Use Value: VCEO = −45 V allows ≥40 V input-to-output differential; low VCE(sat) minimizes dropout voltage under load. |
| LED Driver Switch | Level Shifter Interface |
|
Use Scenario: Driving 20 mA indicator LEDs from 3.3 V or 5 V logic outputs in industrial control panels. IC Role / Device Role / Timing Role: Saturated PNP switch sinking current from LED anode to VCC. Use Value: IC = −100 mA rating provides 5× safety margin; VCE(sat) ≤ −0.25 V limits power dissipation to <5 mW at 20 mA. |
Use Scenario: Translating 1.8 V logic signals to 5 V or 12 V domains in mixed-voltage microcontroller systems. IC Role / Device Role / Timing Role: Inverting level shifter with pull-up resistor on collector and logic input on base. Use Value: Fast fT = 320 MHz supports >10 MHz switching; guaranteed hFE ensures reliable saturation at low base drive currents. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar PNP small-signal amplifier applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BC557BZL1 | Lower hFE range (120–270 at IC = −2.0 mA); otherwise identical ratings and pinout. | Suitable where gain tolerance is relaxed and cost optimization is prioritized over tight bias stability. | Select BC557BZL1 when circuit gain margin accommodates lower minimum hFE and production cost is critical. |
| BC558CZL1 | Reduced VCEO (−30 V) and VCBO (−30 V); same hFE, fT, and package. | Limited to ≤25 V supply rails; not interchangeable in −40 V applications without redesign. | Choose BC558CZL1 only if system voltage remains below 25 V and higher breakdown margin is unnecessary. |
Compared with BC557BZL1 and BC558CZL1, the BC557CZL1 offers the highest guaranteed hFE among BC557 variants and superior voltage ratings versus BC558, making it optimal for precision biasing and higher-supply analog stages where gain consistency and headroom are non-negotiable.
Availability
BC557CZL1 is available at Aetrix Electronics and suitable for audio preamplifiers, discrete voltage regulators, and LED driver circuits requiring stable component supply, consistent hFE binning, and RoHS-compliant TO-92 packaging.
Supply support for BC557CZL1 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, and sensing solutions for automotive, industrial, and consumer markets.
The BC557CZL1 belongs to onsemi's legacy BC5xx family of general-purpose bipolar transistors, designed for cost-sensitive, high-reliability discrete amplifier and switching applications in industrial controls and audio equipment.
FAQ
What is the maximum collector-emitter voltage rating for BC557CZL1?
The BC557CZL1 has a maximum collector-emitter voltage (VCEO) rating of −45 VDC. This specifies the largest reverse-biased voltage that can be applied between collector and emitter while keeping the base open, without risking avalanche breakdown. Designers must ensure operating VCE stays within this limit, especially during transient conditions or inductive load switching, to maintain long-term reliability of the BC557CZL1.
How does the hFE range of BC557CZL1 compare to other BC557 variants?
The BC557CZL1 is the C-series variant, guaranteeing hFE = 180–500 at IC = −2.0 mA and VCE = −5.0 V, which exceeds the B-series (120–270) and A-series (120–180) ranges. This higher minimum gain improves bias point predictability in production, reduces sensitivity to temperature drift, and lowers required base drive current-making the BC557CZL1 preferred for precision amplifier stages where gain stability is critical.
Is BC557CZL1 RoHS compliant?
Yes, BC557CZL1 is RoHS compliant. The "ZL1" suffix denotes ammo-packaged TO-92, and the "G" suffix (BC557CZL1G) explicitly indicates Pb-free construction. Both versions meet EU RoHS Directive 2011/65/EU requirements, with lead content <1000 ppm and full exemption documentation available from onsemi. The BC557CZL1 maintains identical electrical and thermal specifications regardless of Pb-free status.
What is the thermal resistance from junction to ambient for BC557CZL1?
The BC557CZL1 has a thermal resistance from junction to ambient (RJA) of 200°C/W when mounted on a standard FR-4 PCB with no heatsink. This value assumes typical TO-92 mounting conditions and defines how much temperature rise occurs per milliwatt of power dissipated. At its 625 mW maximum rating, this yields a theoretical ΔT of 125°C above ambient-so operation near max power requires careful board layout and ambient temperature control to keep TJ ≤ 150°C for the BC557CZL1.
Can BC557CZL1 be used as a direct replacement for BC557B in existing designs?
BC557CZL1 is pin-compatible and electrically substitutable for BC557B in most cases, but its higher minimum hFE (180 vs. 120) may shift DC bias points in gain-critical circuits. While no PCB changes are needed due to identical TO-92 footprint and pinout, designers should verify quiescent collector current and VCE in existing layouts. For new designs targeting tighter gain tolerance, the BC557CZL1 is recommended; for legacy cost-optimized builds, BC557B remains viable.
BC557CZL1 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)
BC557CZL1 FAQ
1.How can I place an order for BC557CZL1 through Aetrix?
Please submit a Request for Quotation (RFQ) for BC557CZL1 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 BC557CZL1 reliable?
The price and inventory of BC557CZL1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC557CZL1 is usually 5 days.
3.What payment methods are accepted for BC557CZL1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC557CZL1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BC557CZL1?
BC557CZL1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BC557CZL1 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 BC557CZL1?
For technical support, including BC557CZL1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC557CZL1 requirements.
6.How does Aetrix verify that BC557CZL1 is sourced from the original manufacturer or authorized distributors?
All BC557CZL1 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 BC557CZL1 meets industry standards.
7.What is the process for return or replacement of BC557CZL1?
All BC557CZL1 units undergo pre-shipment inspection (PSI). If there is an issue with BC557CZL1, 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 BC557CZL1 part is unused and in its original packaging.
Return procedure for BC557CZL1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BC557CZL1 Tags
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