Texas Instruments CSD18511Q5AT

Overview

CSD18511Q5AT from Texas Instruments is a 40 V, 1.9 mΩ N-channel NexFET™ power MOSFET in an 8-pin SON 5 mm × 6 mm package, optimized for high-efficiency DC-DC conversion and synchronous rectification with logic-level gate drive (V_GS(th) = 1.8 V), 63 nC total gate charge, and avalanche-rated ruggedness.

For engineers reviewing the CSD18511Q5AT datasheet, CSD18511Q5AT pinout, CSD18511Q5AT application, or CSD18511Q5AT equivalent, key selection criteria include R_DS(on) at 4.5 V (2.7 mΩ), thermal resistance (R_θJC = 1.2 °C/W), and Q_gd/Q_g ratio (11.2/63 nC) for switching loss optimization in high-frequency power stages.

Technical Context

This device employs a trench-gate silicon process to achieve low on-resistance and fast switching dynamics. Its gate charge profile (Q_g = 63 nC at 10 V, Q_gd = 11.2 nC) supports efficient operation in hard-switched and synchronous buck topologies up to 1 MHz.

The 8-pin VSONP (DQJ) package integrates an exposed thermal pad for direct PCB heat sinking, enabling continuous drain current of 100 A (package-limited) and pulsed current up to 400 A, with junction-to-case thermal resistance of 1.2 °C/W under defined mounting conditions.

Key Specifications

Pinout & Package

The CSD18511Q5AT uses an 8-pin VSONP (DQJ) plastic package with 5 mm × 6 mm footprint and 1.1 mm max height, featuring an exposed thermal pad (pins 1–4 and 5–8 are source/drain terminals; pin 5 is gate). Mounting requires soldering the thermal pad to a dedicated PCB copper area per TI SLUA271 guidelines.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IRLHS6342TRPBF and SiR872DP-T1-GE3, the CSD18511Q5AT delivers superior thermal performance (1.2 °C/W vs ≥2.5 °C/W) and guaranteed avalanche capability-critical for motor control and unregulated input stages-while maintaining competitive R_DS(on) and gate drive compatibility.

Availability

CSD18511Q5AT is available at Aetrix Electronics and suitable for DC-DC conversion, battery motor control, and industrial BLDC inverter applications requiring stable component supply, long-term lifecycle support, and traceable sourcing for production programs.

Supply support for CSD18511Q5AT 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 over 90 years of innovation in high-reliability electronic components.

The CSD18511Q5AT belongs to TI's NexFET™ power MOSFET product line, engineered specifically for high-frequency, high-current power conversion systems where low R_DS(on), fast switching, and thermal efficiency are essential.

FAQ

What is the maximum continuous drain current for CSD18511Q5AT at 25°C case temperature?

The CSD18511Q5AT supports 159 A continuous drain current when silicon-limited at T_C = 25°C, though the package-limited rating is 100 A. Actual usable current depends on PCB layout, thermal interface, and ambient conditions-TI specifies 100 A as the safe, tested limit for standard 1-inch² 2-oz copper mounting per SLPS631.

Does CSD18511Q5AT require a gate resistor for stable operation?

Yes, a gate resistor is required to control dV/dt and suppress oscillation. TI recommends 5–10 Ω for most 500 kHz–1 MHz applications, based on CSD18511Q5AT's 0.7–1.4 Ω intrinsic gate resistance and 63 nC gate charge. Layout parasitics and driver strength must be evaluated alongside the resistor value to avoid shoot-through or excessive switching loss.

Can CSD18511Q5AT be used in avalanche mode repeatedly?

No-CSD18511Q5AT is avalanche-rated for single-pulse events only (E_AS = 157 mJ, ID = 56 A, L = 0.1 mH). Repeated avalanche operation causes cumulative junction degradation and is not characterized or guaranteed. For repetitive inductive switching, proper snubber design or active clamp circuits are required.

What is the recommended PCB land pattern for CSD18511Q5AT's thermal pad?

Texas Instruments specifies a 4.9 mm × 4.46 mm thermal pad with eight 0.65 mm diameter thermal vias (0.3 mm annular ring) connecting to inner-layer ground planes. This pattern achieves R_θJC = 1.2 °C/W; deviation reduces thermal performance and risks premature thermal shutdown or parametric shift under sustained load.

Is CSD18511Q5AT compatible with lead-free reflow profiles?

Yes, CSD18511Q5AT has a Moisture Sensitivity Level (MSL) rating of Level-1 at 260°C peak reflow temperature and uses Sn (tin) lead finish. It complies with JEDEC J-STD-020 and supports standard Pb-free reflow profiles with ramp rates ≤3°C/s and time above 217°C ≤60 seconds, provided moisture preconditioning per MSL-1 is observed.