Texas Instruments TPS3852H33QDRBRQ1

Overview

TPS3852H33QDRBRQ1 from Texas Instruments is a high-accuracy AEC-Q100 Grade 1 voltage supervisor with integrated window watchdog timer, designed for automotive safety-critical systems. It delivers 0.8% undervoltage threshold accuracy over –40°C to +125°C, ±15% factory-programmed watchdog timing accuracy, and 200 ms reset timeout (tRST), enabling reliable power monitoring and fault detection in microcontroller-based ADAS and telematics units.

For engineers reviewing the TPS3852H33QDRBRQ1 datasheet, TPS3852H33QDRBRQ1 pinout, TPS3852H33QDRBRQ1 application, or TPS3852H33QDRBRQ1 equivalent, key selection criteria include its 3.3 V nominal monitored rail support, open-drain RESET/WDO outputs, manual reset (MR) input, watchdog disable via SET1, and wettable-flank 3 mm × 3 mm VSON-8 package for automated optical inspection.

Technical Context

The TPS3852H33QDRBRQ1 implements a precision undervoltage comparator with 0.5% hysteresis and a dedicated window watchdog state machine that requires WDI falling edges to occur strictly between tWDL(max) and tWDU(min). Its internal 375 nA CWD charging current enables capacitor-programmable watchdog timing, while factory defaults provide fixed 800 ms / 1600 ms boundaries when CWD is unconnected or pulled up with 10 kΩ.

RESET assertion is triggered when VDD falls below VITN = 3.168 V (0.8% accurate at 3.3 V), and deasserts only after VDD rises above VITN + VHYST and tRST = 200 ms elapses. The device operates across 1.6 V–6.5 V supply range with 10 µA typical IDD and supports both active-low MR initiation and watchdog-independent WDO fault signaling.

Key Specifications

Pinout & Package

TPS3852H33QDRBRQ1 uses an 8-pin VSON package (3.00 mm × 3.00 mm) with exposed thermal pad connected internally to GND. Wettable flanks facilitate post-reflow optical inspection of solder joints.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3852H33QDRBRQ1, TPS3851H33QDRBRQ1 trades window watchdog capability and tighter timing accuracy for lower cost, while MAX6373KA33+T sacrifices automotive qualification, programmability, and precision to fit into legacy SO-8 layouts - neither offers the combined AEC-Q100 Grade 1, 0.8% accuracy, and window watchdog functionality of the original.

Availability

TPS3852H33QDRBRQ1 is available at Aetrix Electronics and suitable for automotive ADAS, telematics control units, and FPGA-based radar processors requiring stable component supply under AEC-Q100 conditions.

Supply support for TPS3852H33QDRBRQ1 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 specializing in analog and embedded processing technologies, with leadership in automotive-grade ICs and functional safety solutions.

The TPS3852-Q1 product line delivers high-accuracy voltage supervision and window watchdog functionality specifically for ASIL-B automotive systems, targeting vision processing, radar, and connectivity ECUs where deterministic fault response is mandatory.

FAQ

What is the nominal monitored voltage for TPS3852H33QDRBRQ1?

The TPS3852H33QDRBRQ1 is factory-configured for 3.3 V nominal supply monitoring, with an undervoltage threshold V_ITN = 3.168 V (0.8% below 3.3 V) and hysteresis of 0.5% - meaning it asserts RESET when VDD falls below 3.168 V and releases RESET only after VDD rises above 3.168 V + 15.84 mV and the 200 ms t_RST delay completes.

How does the window watchdog function in TPS3852H33QDRBRQ1?

The TPS3852H33QDRBRQ1 implements a true window watchdog: WDI falling edges must occur strictly between t_WDL(max) and t_WDU(min) to avoid WDO assertion. For factory defaults, this window is 920 ms to 1360 ms. If WDI pulses too early (<680 ms) or too late (>1840 ms), WDO goes low - providing fault discrimination beyond simple timeout detection.

Can TPS3852H33QDRBRQ1 be used with non-3.3 V rails?

Yes - although TPS3852H33QDRBRQ1 is optimized for 3.3 V monitoring, its VDD supply range (1.6 V–6.5 V) and internal reference architecture allow use with other rails. However, the undervoltage threshold is fixed at 3.168 V; for 5 V or 1.8 V rails, a resistor divider is required on VDD to scale the monitored voltage to match the device's threshold.

What is the purpose of the SET1 pin on TPS3852H33QDRBRQ1?

The SET1 pin on TPS3852H33QDRBRQ1 controls watchdog enable/disable: grounding SET1 disables the watchdog timer entirely, causing WDI to be ignored and WDO to enter high-impedance state. This allows safe debug mode or bootloader execution without triggering unwanted watchdog timeouts - while maintaining full undervoltage supervision via RESET.

Does TPS3852H33QDRBRQ1 support capacitor-programmable watchdog timing?

Yes - connecting a capacitor (100 pF to 1 µF) between CWD and GND enables user-programmable watchdog timing. The device's internal 375 nA current source charges the capacitor; t_WDU(typ) = 77.4 × C_CWD(µF) + 0.055 seconds. For example, a 100 nF capacitor yields ~8.7 ms upper boundary, while 1 µF gives ~77.5 s - offering wide flexibility without trimming resistors.