NXP Semiconductors BAP1321-02,115

Overview

BAP1321-02,115 from NXP Semiconductors is a silicon PIN diode optimized for RF attenuator and switch applications up to 3 GHz, featuring low diode capacitance (0.25–0.45 pF at 1 MHz), low forward resistance (0.85–5.0 Ω depending on bias current), and very low series inductance (0.6 nH). It operates with continuous reverse voltage up to 60 V and forward current up to 100 mA in an ultra-small SOD523 package.

For engineers reviewing the BAP1321-02,115 datasheet, BAP1321-02,115 pinout, BAP1321-02,115 application, or BAP1321-02,115 equivalent, key selection criteria include RF insertion loss (as low as 0.08 dB at 900 MHz/100 mA), isolation performance (16.3 dB at 900 MHz), charge carrier lifetime (0.5 µs), thermal resistance (85 K/W), and SOD523 footprint compatibility in high-frequency PCB layouts.

Technical Context

The BAP1321-02,115 functions as a voltage-controlled RF resistor: its forward resistance (rD) varies inversely with DC bias current (0.85 Ω at 100 mA → 5.0 Ω at 0.5 mA), enabling precise analog attenuation control. Its low capacitance (0.25 pF at 20 V reverse bias) and minimal series inductance (0.6 nH) preserve impedance matching and signal integrity in 50 Ω stripline circuits up to 2.45 GHz.

It exhibits fast switching behavior with a charge carrier lifetime of 0.5 µs under defined transient conditions (IF = 10 mA → IR = 6 mA, RL = 100 Ω), supporting moderate-speed RF switching. The device is thermally characterized with Rth j-s = 85 K/W, indicating direct junction-to-soldering-point heat dissipation critical for power handling in compact RF modules.

Key Specifications

Pinout & Package

Package: SOD523 - ultra-small surface-mount plastic package (1.25 × 0.85 × 0.65 mm), marked "K7", cathode indicated by marking bar.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BAR63-02V and MADP-000907-14020T, the BAP1321-02,115 delivers balanced RF performance (0.25–0.45 pF Cd, 0.85–5.0 Ω rD) in a proven SOD523 footprint with documented 0.6 nH LS and 0.5 µs τL - making it optimal for space-constrained, multi-band cellular and ISM switch/attenuator designs where thermal and layout continuity are critical.

Availability

BAP1321-02,115 is available at Aetrix Electronics and suitable for RF attenuators, cellular front-end switches, and 2.4 GHz ISM transceiver modules requiring stable component supply, consistent parametric performance across production lots, and long-term lifecycle availability.

Supply support for BAP1321-02,115 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 consumer applications.

The BAP1321-02,115 belongs to NXP's high-frequency discrete portfolio, designed specifically for RF signal conditioning in compact wireless infrastructure and portable communication devices operating below 3 GHz.

FAQ

What is the maximum reverse voltage rating for BAP1321-02,115?

The BAP1321-02,115 has a continuous reverse voltage (VR) rating of 60 V, as specified in the Absolute Maximum Ratings table. This value defines the highest DC or peak RF voltage the diode can withstand in the off-state without breakdown. Exceeding this limit risks permanent damage. The BAP1321-02,115 must be operated within this constraint in all RF switch and attenuator configurations where reverse bias is applied.

How does forward current affect the RF performance of BAP1321-02,115?

Forward current directly controls the BAP1321-02,115's RF forward resistance (rD): at 100 mA, rD is 0.85–1.3 Ω, yielding minimal insertion loss (0.08 dB at 900 MHz); at 0.5 mA, rD rises to 3.4–5.0 Ω, increasing loss to 0.23 dB. This tunability enables precise analog attenuation. The BAP1321-02,115 datasheet provides rD vs. IF curves and corresponding |s21|² data across 0.5–100 mA, confirming its use as a current-controlled RF resistor.

What is the thermal resistance of BAP1321-02,115 and how does it impact power handling?

The BAP1321-02,115 has a thermal resistance from junction to soldering point (Rth j-s) of 85 K/W. This means a temperature rise of 85 K occurs per watt dissipated at the die. With a maximum total power dissipation (Ptot) of 715 mW at Ts ≤ 90 °C, the BAP1321-02,115 supports sustained bias in compact RF modules. Proper PCB copper area under the SOD523 pad is essential to maintain Ts ≤ 90 °C and avoid thermal derating of electrical specs.

Can BAP1321-02,115 be used in 5G sub-6 GHz applications?

The BAP1321-02,115 is characterized up to 2.45 GHz (with isolation and insertion loss data at 900/1800/2450 MHz) and rated for operation up to 3 GHz. While it meets specifications for LTE and Wi-Fi 6 bands below 2.7 GHz, it lacks published performance data for 3.5 GHz or 4.9 GHz 5G NR bands. For 5G sub-6 GHz designs, verify BAP1321-02,115's |s21|² and Cd at target frequencies using lab measurement - the BAP1321-02,115 is not guaranteed for those bands without additional validation.

What does the marking code 'K7' indicate on the BAP1321-02,115 package?

'K7' is the manufacturer's top-side marking code for the BAP1321-02,115, identifying the specific device variant and wafer lot. Per the datasheet, the marking bar adjacent to pin 1 denotes the cathode terminal. This marking aligns with NXP's standard SOD523 labeling convention and enables visual polarity verification during manual or automated placement. The BAP1321-02,115 must be oriented with the 'K7' mark and bar correctly aligned to ensure proper circuit functionality.