Texas Instruments CSD17505Q5A

Overview

CSD17505Q5A from Texas Instruments is a 30V, N-channel NexFET™ power MOSFET in an 8-pin SON (5 mm × 6 mm) package, optimized for high-efficiency synchronous buck converters in point-of-load applications. It delivers R_DS(on) = 2.9 mΩ at V_GS = 10 V and 20 A, gate charge Q_g = 10 nC, and avalanche-rated operation up to 290 mJ - enabling low conduction and switching losses in telecom, networking, and computing power stages.

For engineers reviewing the CSD17505Q5A datasheet, CSD17505Q5A pinout, CSD17505Q5A application, or CSD17505Q5A equivalent, key selection criteria include its ultralow Q_g/Q_gd, thermal resistance R_θJC = 1.3°C/W, ±20 V gate rating, and SON-8 package compatibility with high-density PCB layouts requiring minimal footprint and thermal management headroom.

Technical Context

This MOSFET employs a trench-gate silicon process optimized for fast switching and low on-resistance in hard-switched DC/DC topologies. Its gate threshold voltage (V_GS(th) = 1.3 V typ) supports 4.5 V logic-level drive, while low reverse transfer capacitance (C_rss = 65–85 pF) minimizes Miller-induced shoot-through risk in synchronous rectification.

The device features integrated body diode with V_SD = 0.8–1.0 V at 20 A and Q_rr = 30 nC, enabling efficient freewheeling in buck converters. Its 1.3°C/W junction-to-case thermal resistance allows direct thermal coupling to PCB copper pads, supporting continuous 24 A operation at T_C = 25°C without forced airflow.

Key Specifications

Pinout & Package

Package: SON-8 (VSONP/DQJ), 5 mm × 6 mm, exposed thermal pad, RoHS-compliant Sn lead finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar N-channel power MOSFET applications.

Compared with IRF7759L2TRPBF and SiR872DP-T1-GE3, the CSD17505Q5A offers the best balance of ultralow Q_g, industry-leading thermal resistance, and compact SON-8 footprint - making it optimal for high-frequency, high-current POL converters where layout area and thermal headroom are constrained.

Availability

CSD17505Q5A is available at Aetrix Electronics and suitable for point-of-load synchronous buck, server VRM output stages, telecom base station PSUs, and networking switch ASIC power applications requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for CSD17505Q5A 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

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and power management technologies, with decades of expertise in high-reliability power conversion solutions.

The CSD17505Q5A belongs to TI's NexFET™ power MOSFET product line, engineered specifically for minimizing conduction and switching losses in high-frequency, high-current DC/DC converters used in computing, telecom, and industrial infrastructure.

FAQ

What is the maximum continuous drain current for the CSD17505Q5A at 25°C case temperature?

The CSD17505Q5A supports a continuous drain current of 100 A at T_C = 25°C, as specified in its Absolute Maximum Ratings table. This rating assumes ideal thermal conditions - actual usable current depends on PCB copper area, ambient temperature, and airflow. For sustained 24 A operation at room ambient, the CSD17505Q5A requires only a 1-inch² 2-oz copper pad per TI's recommended layout.

Does the CSD17505Q5A support 3.3 V gate drive in practical applications?

Yes, the CSD17505Q5A has a typical gate threshold voltage of 1.3 V and achieves full enhancement at V_GS = 4.5 V, making it compatible with 3.3 V logic-level drivers. At V_GS = 4.5 V and I_D = 20 A, its R_DS(on) is 3.7 mΩ - still sufficiently low for high-efficiency operation in 3.3 V-controlled POL converters. The CSD17505Q5A datasheet confirms this performance across temperature.

What is the thermal resistance from junction to case (R_θJC) for the CSD17505Q5A, and how does it impact heatsink design?

The CSD17505Q5A has a junction-to-case thermal resistance of 1.3°C/W, measured with the device mounted on a 1-inch² 2-oz copper pad. This low value means heat transfers efficiently from the die to the PCB copper, eliminating the need for external heatsinks in most applications. Designers can rely on the PCB itself as the primary thermal path - a key advantage over TO-220 or DPAK MOSFETs with R_θJC > 3°C/W.

Is the CSD17505Q5A avalanche-rated, and what does that mean for circuit reliability?

Yes, the CSD17505Q5A is avalanche-rated with E_AS = 290 mJ (single-pulse, I_D = 76 A, L = 0.1 mH, R_G = 25 Ω). This rating ensures the device can safely absorb inductive energy during abnormal conditions like load dump or controller fault, preventing catastrophic failure in synchronous buck and motor drive applications. The CSD17505Q5A's ruggedness is validated per JEDEC JESD24-1.

What package type and pin configuration does the CSD17505Q5A use, and how does it affect PCB layout?

The CSD17505Q5A uses an 8-pin SON (VSONP/DQJ) package measuring 5 mm × 6 mm with an exposed thermal pad. Pins 1–3 and 5–8 are internally connected to Drain; Pin 4 is Gate; Pins 6–8 and the thermal pad form the Source terminal. This configuration enables low-inductance, high-current routing and direct thermal coupling to inner-layer copper - critical for minimizing voltage spikes and maintaining efficiency in high-frequency POL designs using the CSD17505Q5A.