NXP Semiconductors BAP70-02/AX

Overview

BAP70-02/AX from NXP Semiconductors is a silicon PIN diode in an ultra-small SOD523 surface-mount package, designed as a voltage-controlled RF resistor for precision attenuator circuits. It delivers low diode capacitance (200–250 fF at 20 V), very low series inductance (0.6 nH), and AEC-Q101 qualification for automotive-grade reliability.

For engineers reviewing the BAP70-02/AX datasheet, BAP70-02/AX pinout, BAP70-02/AX application, or BAP70-02/AX equivalent, key selection criteria include reverse voltage rating (50 V), forward resistance tuning range (7 Ω at 10 mA to 1.4 Ω at 100 mA), junction-to-solder-point thermal resistance (145 K/W), and RF performance up to 100 MHz.

Technical Context

The BAP70-02/AX operates as a current-biased RF variable resistor by modulating carrier lifetime in its intrinsic region. Its planar structure and optimized geometry yield stable capacitance vs. reverse voltage behavior (570 fF at 0 V → 200 fF at 20 V) and predictable forward resistance vs. DC bias (100 Ω at 0.5 mA → 1.4 Ω at 100 mA).

Designed for high-frequency signal path control, it leverages low parasitic inductance (0.6 nH) and minimal package footprint (SOD523, 1.25 × 0.85 mm) to preserve impedance integrity in compact RF layouts. The cathode-marked SOD523 outline ensures unambiguous orientation during automated placement.

Key Specifications

Pinout & Package

Package: SOD523 - ultra-compact plastic surface-mount package (1.25 × 0.85 × 0.65 mm), cathode indicated by marking bar.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PIN diode RF attenuator applications.

Compared with BAR63-02V and MMBAP70-02, the BAP70-02/AX provides guaranteed AEC-Q101 validation and tighter Cd tolerance (200–250 fF), making it preferred for automotive RF front-ends where thermal reliability and impedance stability are critical.

Availability

BAP70-02/AX is available at Aetrix Electronics and suitable for SAT TV tuners, car radio RF attenuators, and UHF wireless microphone receivers requiring stable component supply across automotive and broadcast equipment production cycles.

Supply support for BAP70-02/AX 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 BAP70-02/AX belongs to NXP's high-frequency discrete portfolio, engineered specifically for RF signal conditioning in space-constrained, thermally demanding environments such as automotive infotainment and satellite reception systems.

FAQ

What is the maximum reverse voltage rating for the BAP70-02/AX?

The BAP70-02/AX has a maximum continuous reverse voltage (VR) rating of 50 V, as defined in its Absolute Maximum Ratings table. This value represents the upper limit for safe DC blocking or RF signal swing in attenuator configurations. Exceeding 50 V risks irreversible junction breakdown. The BAP70-02/AX maintains stable capacitance down to 200 fF at 20 V reverse bias, supporting robust operation well within this limit.

How does forward current affect the RF resistance of the BAP70-02/AX?

The BAP70-02/AX exhibits a strong inverse relationship between forward current (IF) and RF forward resistance (rD): rD drops from ~100 Ω at 0.5 mA to 1.4 Ω at 100 mA (typical, f = 100 MHz). This behavior enables precise analog gain control in attenuator designs. The BAP70-02/AX achieves this via carrier injection into its intrinsic region, with τL = 1.25 μs ensuring predictable settling time during current modulation.

Is the BAP70-02/AX qualified for automotive applications?

Yes, the BAP70-02/AX is AEC-Q101 qualified, confirming its suitability for automotive electronic systems. This qualification covers stress tests including temperature cycling, humidity bias, and mechanical shock. The BAP70-02/AX operates reliably from −40 °C to +125 °C ambient and supports junction temperatures up to +150 °C, making it appropriate for under-hood and infotainment RF modules where the BAP70-02/AX is deployed.

What is the package type and marking convention for the BAP70-02/AX?

The BAP70-02/AX uses the SOD523 surface-mount package (1.25 × 0.85 × 0.65 mm) with a cathode-indicating marking bar. Its marking code is "K8", printed adjacent to the bar. This compact outline allows high-density RF layout while ensuring unambiguous polarity identification during automated assembly-critical for consistent BAP70-02/AX performance in production.

What is the typical diode capacitance of the BAP70-02/AX at 20 V reverse bias?

The BAP70-02/AX has a typical diode capacitance (Cd) of 200 fF at 20 V reverse bias, with a maximum specified value of 250 fF. This low, voltage-dependent capacitance enables stable impedance matching in UHF front-ends. At lower reverse voltages (e.g., 1 V), Cd rises to 400 fF, allowing designers to exploit the BAP70-02/AX's tunable reactance for adaptive filtering or matching networks.