Texas Instruments CSD43301Q5M

Overview

CSD43301Q5M from Texas Instruments is a NexFET™ Smart Synchronous Rectifier integrating a high-efficiency 0.55 mΩ (typ) MOSFET and dedicated gate driver in a single LSON-CLIP (DQP) package. It delivers up to 80 A continuous output current with TTL/CMOS-compatible IN and SD inputs, and operates at switching frequencies up to 1500 kHz - optimized for secondary-side synchronous rectification in high-density DC/DC converters.

For engineers reviewing the CSD43301Q5M datasheet, CSD43301Q5M pinout, CSD43301Q5M application, or CSD43301Q5M equivalent, key selection considerations include its ultra-low R_DS(on), integrated UVLO with 300 mV hysteresis, 5-mm × 6-mm SON footprint, thermal resistance of 2°C/W (J-B), and TTL/CMOS input thresholds independent of V_DD.

Technical Context

The CSD43301Q5M implements a monolithic synchronous rectifier architecture where the internal MOSFET and driver share a common PGND reference and are co-packaged to minimize parasitic inductance. Its input logic (IN/SD) uses voltage-threshold-based control with 2.0 V high-level and 0.8 V low-level thresholds, plus 0.8 V hysteresis for noise immunity.

It features an under-voltage lockout (UVLO) circuit with 4.2 V turn-on threshold and 300 mV hysteresis, ensuring safe startup/shutdown by holding the MOSFET off until V_DD stabilizes. Propagation delays are tightly specified: t_PDLH = 32 ns (IN→DRAIN), t_PDHL = 80 ns (IN→DRAIN), and matching SD-controlled timing.

Key Specifications

Pinout & Package

LSON-CLIP (DQP) package with 12 terminals, 5 mm × 6 mm footprint, and exposed thermal pad (Pin 13) for primary heat dissipation. Dual PGND pins (7 & 13) must be connected on PCB; NC pins (1,2,4,8,10,11) require dead-copper connection only.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous rectifier applications.

Compared with CSD43301Q5M, the CSD43302Q5M trades 0.2 mΩ higher R_DS(on) for enhanced gate drive margin, while the TPS40303DRCT offers full timing programmability at the cost of increased component count, layout complexity, and thermal management effort.

Availability

CSD43301Q5M is available at Aetrix Electronics and suitable for server VRMs, telecom POL converters, and GPU voltage regulators requiring stable component supply, long-lifecycle support, and RoHS-compliant manufacturing.

Supply support for CSD43301Q5M 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 components.

The CSD43301Q5M belongs to TI's NexFET™ Smart Power Stage family, engineered specifically for high-efficiency, high-density secondary-side synchronous rectification in advanced DC/DC converters.

FAQ

What is the maximum continuous current rating for the CSD43301Q5M?

The CSD43301Q5M is rated for 80 A continuous output current under recommended operating conditions (T_A = 25°C, proper PCB thermal design). This rating assumes use of the recommended thermal vias and copper pour per TI's layout guidelines. Peak current capability reaches 120 A for pulses ≤50 µs, supporting transient-heavy loads like CPU/GPU VRMs.

Does the CSD43301Q5M require an external gate resistor?

No, the CSD43301Q5M does not require an external gate resistor because the gate driver and MOSFET are monolithically integrated within the same die and package. The internal driver is optimized for the specific FET characteristics, eliminating layout-dependent ringing and simplifying design. External resistors would degrade timing performance and are not recommended.

How does the UVLO function protect the CSD43301Q5M during power-up?

The CSD43301Q5M's UVLO holds the internal MOSFET OFF until V_DD rises above 4.2 V (typ), preventing linear-mode operation and potential thermal runaway. With 300 mV hysteresis, it avoids chatter during supply droop. This ensures the CSD43301Q5M only switches when the driver has sufficient bias, protecting both itself and the downstream load during unstable input conditions.

Can the CSD43301Q5M be used with a 3.3 V PWM controller?

Yes, the CSD43301Q5M supports 3.3 V PWM controllers directly: its IN and SD inputs have TTL/CMOS-compatible thresholds (V_INH = 2.0 V, V_INL = 0.8 V) that are independent of V_DD. A 3.3 V logic high exceeds the 2.0 V threshold with margin, and the 0.8 V low threshold ensures noise immunity - no level shifter is needed for interfacing with standard 3.3 V digital controllers.

What is the thermal resistance from junction to board (R_θJB) for the CSD43301Q5M?

The CSD43301Q5M has a typical R_θJB of 2°C/W when mounted per TI's recommended PCB layout - including connection of Pins 7 and 13 to a solid thermal pad with ≥9 thermal vias (0.3 mm drill, tented). This value reflects heat flow from the silicon junction through the clip-bonded structure into the PCB, making it highly effective for convection-cooled applications without heatsinks.