My Inquiry
My Account
NXP Semiconductors BF556A,235
- Part No.:
- BF556A,235
- Manufacturer:
- NXP Semiconductors
- Category:
- Single FETs, MOSFETs
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
BF556A,235.pdf
- Description:
- RF MOSFET JFET 30V SOT23
- Quantity:
- Payment:
- Shipping:
Inventory:2,296
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
BF556A,235 from NXP Semiconductors is an N-channel symmetrical silicon junction field-effect transistor (JFET) in SOT23 package, designed for low-noise, high-impedance signal conditioning. It delivers IDSS = 3–7 mA, VGSoff = −0.5 to −7.5 V, and |yfs| = 4.5 mS at VDS = 15 V, enabling precise biasing in electret microphone preamplifiers and infrared detector interfaces.
For engineers reviewing the BF556A,235 datasheet, BF556A,235 pinout, BF556A,235 application, or BF556A,235 equivalent, key selection criteria include gate leakage (typ. 500 fA), cut-off voltage spread, SOT23 thermal resistance (Rth(j-a) = 500 K/W), and VHF small-signal gain stability up to 450 MHz.
Technical Context
The BF556A,235 operates as a depletion-mode JFET with symmetrical source/drain terminals, requiring zero-gate-voltage bias for nominal conduction. Its low IGSS (−0.5 pA typ.) and high V(BR)GSS (−30 V) support stable DC-coupled impedance transformation in sensitive analog front-ends.
Dynamic performance is characterized by Ciss = 3 pF and Crss = 0.9 pF at VGS = 0 V, f = 1 MHz, and gfs = 2 mS at 100 MHz - confirming suitability for VHF oscillator and mixer stages where capacitance matching and phase linearity are critical.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| IDSS | 3–7 mA at VGS = 0 V, VDS = 15 V: sets baseline transconductance range for bias point selection in high-Z amplifiers. |
| VGSoff | −0.5 to −7.5 V at ID = 200 µA, VDS = 15 V: defines usable gate voltage swing before pinch-off in linear operation. |
| |yfs| | 4.5 mS min at VGS = 0 V, VDS = 15 V: ensures sufficient small-signal gain for low-level signal amplification. |
| IGSS | −0.5 pA typ. at VGS = −20 V, VDS = 0 V: enables ultra-low input current in electret microphone bias networks. |
| Ciss / Crss | 3 pF / 0.9 pF at VDS = 15 V, f = 1 MHz, VGS = 0 V: supports stable VHF tuning without excessive Miller effect in oscillator tanks. |
| Ptot | 250 mW at Tamb ≤ 25 °C: limits continuous dissipation in compact SOT23 layouts without forced cooling. |
| Rth(j-a) | 500 K/W on FR4 PCB: informs thermal design margin for ambient temperatures up to +70 °C in sealed enclosures. |
Pinout & Package
SOT23 plastic surface-mounted package (TO-236AB), 3-lead, dimensions per IEC/JEDEC standard: D = 2.8 mm, E = 1.4 mm, Lp = 1.2 mm, e = 1.9 mm, bp = 0.48 mm.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Source (s) | Symmetrical terminal; interchangeable with drain in depletion-mode operation; connects to reference node in common-source amplifier. |
| 2 | Drain (d) | Output current terminal; requires ≥10 mm² copper pad for thermal management per datasheet mounting guideline. |
| 3 | Gate (g) | High-impedance control terminal; must be protected from ESD per caution note; ties to bias network or AC ground in RF applications. |
Key Features
| Feature | Design Value |
|---|---|
| Low gate leakage | 500 fA typical enables >10⁹ Ω input impedance in electret microphone bias circuits without droop. |
| High forward transfer admittance | 4.5 mS minimum ensures robust small-signal gain in low-power VHF amplifiers without external gain staging. |
| Symmetrical construction | Source/drain interchangeability simplifies layout in bidirectional signal paths and cascode configurations. |
| ESD-sensitive gate | Requires handling per IEC 61340-5-1; PCB guard rings and series resistors recommended for production assembly. |
Applications
| Electret Microphone Interface | Infrared Detector Front-End |
|---|---|
Use Scenario: Biasing and buffering of electret condenser microphones in portable audio devices. IC Role / Device Role / Timing Role: JFET acts as ultra-high-impedance impedance converter and first-stage amplifier. Use Value: 500 fA gate leakage preserves microphone capsule charge, preventing low-frequency roll-off and distortion below 100 Hz. |
Use Scenario: Signal conditioning for pyroelectric infrared sensors in motion detection systems. IC Role / Device Role / Timing Role: Low-noise JFET provides DC-coupled amplification of weak IR detector output currents. Use Value: 40 nV/√Hz input noise at 100 Hz ensures reliable detection of sub-mV sensor signals amid ambient thermal drift. |
| VHF Oscillator Core | Mixer Stage in RF Receivers |
Use Scenario: Active device in Colpitts or Clapp oscillator topologies operating at 30–200 MHz. IC Role / Device Role / Timing Role: Gain element sustaining oscillation with minimal phase noise contribution. Use Value: 3 pF input capacitance and 0.9 pF reverse transfer capacitance enable stable tank resonance without parasitic pulling. |
Use Scenario: Passive or active mixer core in superheterodyne receivers for wireless sensor nodes. IC Role / Device Role / Timing Role: Transconductance device converting RF and LO signals into IF sum/difference products. Use Value: 2 mS transfer conductance at 100 MHz maintains conversion gain while minimizing LO feedthrough due to symmetrical structure. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar JFET amplifier applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 2N4416A | IDSS = 5–15 mA, VGSoff = −1.5 to −5 V, Ciss = 5 pF - wider parameter spread and higher capacitance. | Less suitable for low-leakage electret bias; better for general-purpose RF amplification where tighter VGSoff control is not required. | Select when broader IDSS tolerance is acceptable and higher power dissipation (350 mW) is available. |
| J310 | IDSS = 24–60 mA, VGSoff = −0.5 to −3.5 V, |yfs| = 12–40 mS - significantly higher gain and current, but no guaranteed 500 fA leakage. | Better for high-gain preamp stages; unsuitable for ultra-low-current IR detectors due to higher IGSS (typ. 1 nA). | Choose only if system requires >10× higher transconductance and can tolerate reduced input impedance. |
Compared with 2N4416A and J310, the BF556A,235 offers the narrowest VGSoff range and lowest confirmed gate leakage, making it uniquely suited for precision high-impedance analog interfaces where leakage-induced offset and noise dominate performance.
Availability
BF556A,235 is available at Aetrix Electronics and suitable for electret microphone interfaces, infrared detector front-ends, VHF oscillator designs, and RF mixer stages requiring stable component supply across industrial and consumer electronics programs.
Supply support for BF556A,235 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
NXP Semiconductors is a global semiconductor company headquartered in Eindhoven, Netherlands, specializing in secure connectivity solutions for automotive, industrial, and IoT applications.
The BF556A,235 belongs to NXP's legacy silicon JFET product line, engineered specifically for low-noise, high-input-impedance analog signal conditioning in battery-powered and space-constrained systems.
FAQ
What is the maximum drain-source voltage rating for BF556A,235?
The BF556A,235 has a maximum drain-source voltage (VDS) rating of ±30 V under DC conditions, as specified in the Absolute Maximum Ratings table. This rating applies regardless of gate bias and must not be exceeded to prevent permanent device damage. Operation above this limit violates IEC 60134 stress guidelines and voids reliability guarantees.
Does BF556A,235 have a specified gate-source breakdown voltage?
Yes, the BF556A,235 specifies a gate-source breakdown voltage V(BR)GSS of −30 V at IG = −1 µA and VDS = 0 V. This parameter confirms the gate junction's ability to withstand reverse bias without avalanche conduction, supporting robust ESD protection design when combined with external clamping.
How does the BF556A,235 differ from BF556B and BF556C variants?
The BF556A,235 differs from BF556B and BF556C solely in its IDSS and VGSoff ranges: BF556A has IDSS = 3–7 mA and VGSoff = −0.5 to −7.5 V, whereas BF556B and BF556C offer progressively higher IDSS (6–13 mA and 11–18 mA) and more negative VGSoff. All share identical package, pinout, thermal specs, and dynamic characteristics.
Is BF556A,235 suitable for use in automotive applications?
No, the BF556A,235 is not automotive-qualified. The NXP datasheet explicitly states that unless otherwise indicated, non-automotive qualified products like BF556A,235 are neither tested nor warranted for automotive use. Its qualification level is industrial, with no AEC-Q101 stress testing or extended temperature validation.
What is the thermal resistance from junction to ambient for BF556A,235?
The BF556A,235 has a typical thermal resistance Rth(j-a) of 500 K/W when mounted on an FR4 PCB with 4 mm lead length and a 10 mm² drain pad. This value assumes standard JEDEC test conditions and must be derated linearly above Tamb = 25 °C using the power derating curve in Figure 1 of the datasheet.
BF556A,235 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- NXP Semiconductors
- Series:
- -
- Package/Case:
- TO-236-3, SC-59, SOT-23-3
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Technology:
- JFET
- Configuration:
- N-Channel
- Frequency:
- -
- Gain:
- -
- Voltage - Test:
- -
- Current Rating (Amps):
- 7mA
- Noise Figure:
- -
- Current - Test:
- -
- Power - Output:
- -
- Voltage - Rated:
- 30 V
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23 (TO-236AB)
BF556A,235 FAQ
1.How can I place an order for BF556A,235 through Aetrix?
Please submit a Request for Quotation (RFQ) for BF556A,235 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 BF556A,235 reliable?
The price and inventory of BF556A,235 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BF556A,235 is usually 5 days.
3.What payment methods are accepted for BF556A,235?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BF556A,235 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BF556A,235?
BF556A,235 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BF556A,235 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 BF556A,235?
For technical support, including BF556A,235 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BF556A,235 requirements.
6.How does Aetrix verify that BF556A,235 is sourced from the original manufacturer or authorized distributors?
All BF556A,235 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 BF556A,235 meets industry standards.
7.What is the process for return or replacement of BF556A,235?
All BF556A,235 units undergo pre-shipment inspection (PSI). If there is an issue with BF556A,235, 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 BF556A,235 part is unused and in its original packaging.
Return procedure for BF556A,235:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BF556A,235 Tags
-
3SK294(TE85L,F)
Toshiba Semiconductor and Storage
-
SAV-551+
Mini-Circuits
-
TAV2-501+
Mini-Circuits
-
CE3514M4-C2
CEL
-
AFT05MS004NT1
NXP USA Inc.
-
SAV-541+
Mini-Circuits
-
CE3512K2-C1
CEL
-
AFM907NT1
NXP Semiconductors
-
SKY65050-372LF
Skyworks Solutions Inc.
-
CE3520K3-C1
CEL
-
AFT09MS007NT1
NXP USA Inc.
-
AFT09MS015NT1
NXP USA Inc.
Tech Hub
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…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
