Texas Instruments TPS274C65BSRHAR

Overview

TPS274C65BSRHAR from Texas Instruments is a quad-channel smart high-side switch with 72 mΩ R_ON, SPI interface, and integrated diagnostics for industrial 24-V systems. It delivers up to 2 A per channel, features adjustable current limiting (250 mA–2.2 A), thermal shutdown, short-to-ground protection, and open-load detection - deployed in PLC digital output modules and IOLink master ports.

For engineers reviewing the TPS274C65BSRHAR datasheet, TPS274C65BSRHAR pinout, TPS274C65BSRHAR application, or TPS274C65BSRHAR equivalent, key selection criteria include its 40-pin VQFN package, absence of reverse current blocking (RCB) and ADC, SPI-controlled fault reporting via FLT pin, and compatibility with 12–36 V supply rails and 3.0–5.5 V logic.

Technical Context

The TPS274C65BSRHAR implements four independent N-channel MOSFET high-side switches with integrated charge pump, enabling operation from 12–36 V VS while supporting 3.0–5.5 V VDD logic. Unlike AS/ASH variants, it omits RCB FET gate drivers, LED drivers, and analog current sense output - confirmed by pin functions (RCBx, ISNS, LEDOUTx marked DNC) and device comparison table.

Its diagnostic architecture relies solely on digital SPI registers and discrete fault signaling: FLT pin asserts open-drain low on any channel fault (overcurrent, thermal, UVLO), while READY indicates SPI readiness. Current limiting is programmable via ILIM_REG[7:0], with no analog current sense path or ADC - verified by "No current sense" entry in Table 4-1 and absence of ISNS functionality in BS version pin table.

Key Specifications

Pinout & Package

TPS274C65BSRHAR uses a 40-pin VQFN package (RHA), 6.0 mm × 6.0 mm, 0.5 mm pitch, with exposed thermal pad connected to GND. Pin count and layout match Figure 5-2 (BS version top view); RCBx, ISNS, LEDOUTx, and multiple DNC pins are unconnected and must be left floating or grounded per layout guidelines.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-side switch applications.

Compared with TPS274C65ASRHAR and TPS274C65ASHRHAR, the TPS274C65BSRHAR provides identical core switching performance and SPI diagnostics but removes unused analog/LED/RCB circuitry - reducing pin count, PCB routing complexity, and system cost for applications that do not require those features.

Availability

TPS274C65BSRHAR is available at Aetrix Electronics and suitable for industrial PLC systems, IOLink master designs, and sensor power distribution networks requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for TPS274C65BSRHAR 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 connectivity technologies for industrial, automotive, and communications markets.

The TPS274C65xS product line delivers robust, SPI-programmable high-side switches optimized for industrial control systems - emphasizing reliability under harsh conditions, diagnostic intelligence, and seamless integration into modular I/O architectures.

FAQ

What is the maximum continuous load current per channel for TPS274C65BSRHAR?

The TPS274C65BSRHAR supports 1.6 A per channel continuously at 85°C ambient temperature with all four channels enabled. At 25°C, it sustains 2 A per channel with thermal margin. Derating curves in Section 6.5 confirm 72 mΩ R_ON at 25°C rising to 110 mΩ at 125°C, directly impacting power dissipation and thermal design.

Does TPS274C65BSRHAR include reverse current blocking (RCB) functionality?

No, TPS274C65BSRHAR does not implement reverse current blocking. Pins RCB1–RCB4 are marked DNC in the BS version pin table (Figure 5-2), and Table 4-1 explicitly states "No" for RCB in the TPS274C65BS row. This distinguishes it from AS/ASH variants and simplifies layout where bidirectional current flow is not required.

Can TPS274C65BSRHAR measure load current analogously like the AS variant?

No, TPS274C65BSRHAR lacks analog current sense capability. The ISNS pin is labeled DNC for the BS version, and Table 4-1 confirms "No current sense" for this variant. Load current monitoring must be implemented externally or inferred from SPI-reported fault events - unlike AS/ASH which provide 1.73 mA output per 1 A load via ISNS.

What is the purpose of the READY pin on TPS274C65BSRHAR?

The READY pin on TPS274C65BSRHAR is an open-drain logic output that pulls low during power-up initialization and transitions high once the internal state machine is ready to accept SPI commands. Its assertion confirms successful POR completion and register readiness - critical for synchronizing host MCU SPI transactions after power application.

How does TPS274C65BSRHAR handle short-circuit faults?

TPS274C65BSRHAR responds to short-circuit faults by activating current limiting at the programmed threshold (e.g., 2.2 A), then asserting the open-drain FLT pin low. If thermal shutdown triggers (160–210°C), it disables outputs and retries after 0.6 ms. No auto-retry occurs for persistent shorts - the host must clear faults via SPI or cycle DO_EN to restore operation.