Texas Instruments TPS3852G33DRBR

Overview

TPS3852G33DRBR from Texas Instruments is a precision voltage supervisor IC with integrated window watchdog timer, designed for system-level power monitoring and fault detection in microcontroller-based applications. It delivers 0.8% undervoltage threshold accuracy over –40°C to +125°C, ±15% factory-programmed watchdog timing accuracy, 10 µA typical supply current, and operates across 1.6 V to 6.5 V VDD. It is used in safety-critical industrial control systems where reliable reset assertion and precise watchdog windowing prevent silent failures.

For engineers reviewing the TPS3852G33DRBR datasheet, TPS3852G33DRBR pinout, TPS3852G33DRBR application, or TPS3852G33DRBR equivalent, key selection considerations include its 3.3-V nominal monitored rail support, programmable CWD timing interface, open-drain RESET/WDO outputs, manual reset (MR) input, and SET1 watchdog enable/disable control - all in an 8-pin VSON package.

Technical Context

The TPS3852G33DRBR implements a dual-threshold undervoltage detection architecture with 0.5% hysteresis, enabling stable reset assertion/deassertion during noisy rail transitions. Its window watchdog uses a dedicated state machine that validates WDI falling edges only within a defined time window (tWDL to tWDU), distinguishing between early, late, and correct timing faults.

It supports three CWD configuration modes: unconnected (NC), 10-kΩ pull-up to VDD (enabling factory-programmed delays), or external capacitor (enabling user-adjustable tWDU via tWDU(typ) = 77.4 × CCWD(µF) + 0.055 s). The device enters high-impedance WDO state when RESET is asserted, decoupling watchdog fault signaling from system reset execution.

Key Specifications

Pinout & Package

TPS3852G33DRBR is housed in a 3.00-mm × 3.00-mm, 8-pin VSON (DRB) package with exposed thermal pad connected internally to GND. The package supports high-density PCB layouts and efficient thermal dissipation via soldered thermal pad connection to ground plane.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar voltage supervisor with watchdog timer applications.

Compared with TPS3852G33DRBR, TPS3851G33DRBR omits window watchdog functionality but retains identical precision supervision, while MAX6373KA33+T trades accuracy and package size for broad industry familiarity - neither matches the combined precision, windowing, and compact VSON integration of the TPS3852G33DRBR.

Availability

TPS3852G33DRBR is available at Aetrix Electronics and suitable for industrial control systems, telematics units, patient monitoring devices, and FPGA-based embedded platforms requiring stable component supply, long-term lifecycle assurance, and guaranteed traceability.

Supply support for TPS3852G33DRBR 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 company headquartered in Dallas, Texas, delivering analog and embedded processing solutions for industrial, automotive, and communications markets.

The TPS385x family was engineered specifically for high-reliability power supervision in safety-critical systems, combining precision voltage monitoring with advanced window watchdog logic to meet ASIL-B and IEC 61508 requirements.

FAQ

What is the nominal monitored voltage for TPS3852G33DRBR?

The TPS3852G33DRBR is factory-configured for 3.3-V nominal supply monitoring, with VITN = 3.168 V (3.3 V × 0.96) and ±0.8% accuracy over –40°C to +125°C. This matches standard 3.3-V microcontroller and FPGA core rails, and the device's hysteresis ensures clean release at VITN + VHYST = 3.168 V × 1.005 ≈ 3.184 V. The TPS3852G33DRBR does not require external resistor dividers for this rail.

How does the CWD pin configure watchdog timing on TPS3852G33DRBR?

The CWD pin on TPS3852G33DRBR selects between three timing modes: unconnected (NC) or 10-kΩ pull-up to VDD enables ±15% accurate factory-programmed windows (e.g., tWDL = 800 ms typ, tWDU = 1600 ms typ); connecting a capacitor to GND enables user-programmable tWDU via tWDU(typ) = 77.4 × CCWD(µF) + 0.055 s. The TPS3852G33DRBR internally evaluates CWD at power-up and locks the mode for the entire operating cycle.

Can TPS3852G33DRBR's WDO output be used independently of RESET?

Yes - the TPS3852G33DRBR provides independent open-drain WDO and RESET outputs. WDO asserts low only when a WDI edge falls outside the programmed window *and* RESET is high; if RESET is asserted (low), WDO enters high-impedance state. This allows WDO to signal watchdog faults (e.g., software hang) without forcing a system reset, enabling diagnostics or graceful shutdown - a key capability of the TPS3852G33DRBR not found in basic supervisors.

What is the function of the SET1 pin on TPS3852G33DRBR?

The SET1 pin on TPS3852G33DRBR is a watchdog enable/disable control: grounding SET1 disables the watchdog timer entirely, forcing WDO into high-impedance and ignoring WDI inputs. This is essential during firmware development or debug sessions to prevent spurious timeouts. When SET1 is high, the watchdog operates normally. The TPS3852G33DRBR supports dynamic toggling of SET1, with a 150-µs setup time required after enabling before WDI edges are recognized.

Does TPS3852G33DRBR support manual reset, and how is it implemented?

Yes - TPS3852G33DRBR includes an active-low manual reset (MR) input (Pin 3). A logic-low pulse ≥1 µs on MR forces immediate RESET assertion, regardless of VDD level, and disables the watchdog during assertion. MR has an internal ~620-nA pull-up to VDD, so it may be left floating or tied to VDD if unused. After MR returns high and VDD exceeds VITN + VHYST, RESET remains low for the full tRST delay (200 ms typ) before deasserting - a behavior confirmed in the TPS3852G33DRBR datasheet timing tables.