Texas Instruments TPS3707-33DGN

Overview

TPS3707-33DGN from Texas Instruments is a precision 3.3 V supply-voltage supervisor IC with active-low and active-high reset outputs, fixed 200 ms power-on reset delay, 2.93 V negative-going threshold (V_IT–), 50 µA max supply current, and integrated power-fail comparator for low-battery warning-used in microcontroller-based industrial control systems requiring reliable brownout detection and dual-reset signaling.

For engineers reviewing the TPS3707-33DGN datasheet, TPS3707-33DGN pinout, TPS3707-33DGN application, or TPS3707-33DGN equivalent, key selection criteria include its dual-reset output architecture (RESET and RESET), absence of watchdog timer, MSOP-PowerPAD™ 8-pin package, –40°C to 85°C operating range, and compatibility with 3.3 V rail supervision in space-constrained embedded designs.

Technical Context

The TPS3707-33DGN implements a precision bandgap reference and comparator-based V_DD monitoring circuit with hysteresis (50 mV) and a dedicated PFI/PFO power-fail path. It asserts active-low RESET when V_DD falls below 2.93 V and releases it after 200 ms once V_DD exceeds the threshold.

Unlike the TPS3705-xx series, the TPS3707-xx variant omits the watchdog timer and instead provides complementary reset outputs: open-drain active-low RESET and push-pull active-high RESET-enabling direct interface with both NMI and standard reset inputs on MSP430, ARM Cortex-M, and other processors without external logic.

Key Specifications

Pinout & Package

TPS3707-33DGN is housed in an 8-pin MSOP-PowerPAD™ package (3.00 mm × 3.00 mm), featuring thermal enhancement via exposed die pad and surface-mount compatibility for high-density PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3707-33DGN, the TPS3707-33D offers identical supervision functionality in a larger, thermally less efficient package, while the MAX706R provides baseline reset capability without power-fail detection or dual-output flexibility-making TPS3707-33DGN the optimal choice for space-constrained, feature-rich industrial and automotive applications.

Availability

TPS3707-33DGN is available at Aetrix Electronics and suitable for industrial programmable controllers, automotive body electronics, and portable medical instrumentation requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for TPS3707-33DGN 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 delivering analog, embedded processing, and connectivity solutions for industrial, automotive, and personal electronics markets.

The TPS370x family was designed specifically for robust, low-component-count power supervision in microprocessor-based systems-emphasizing precision threshold accuracy, dual-output flexibility, and extended temperature reliability without external timing components.

FAQ

What is the exact reset threshold voltage for TPS3707-33DGN?

The TPS3707-33DGN has a guaranteed negative-going input threshold voltage (V_IT–) of 2.93 V, with a tolerance of ±70 mV over the full –40°C to 85°C operating range. This value is factory-trimmed and specified in Section 7.5 of the SLVS184F datasheet. The threshold applies to the V_DD pin and ensures reliable detection of 3.3 V rail brownout conditions. TPS3707-33DGN does not require external calibration or adjustment to achieve this accuracy.

Does TPS3707-33DGN include a watchdog timer function?

No, TPS3707-33DGN does not include a watchdog timer. Unlike the TPS3705-xx series, the TPS3707-xx family replaces the watchdog input/output (WDI/WDO) pins with a second reset output (RESET). Figure 6-4 and Section 8.3.3 of the datasheet explicitly state that TPS3707-xx devices omit the watchdog function. The TPS3707-33DGN provides only V_DD supervision, manual reset (MR), and power-fail monitoring (PFI/PFO).

What is the purpose of the NC pin on TPS3707-33DGN?

Pin 8 of the TPS3707-33DGN is designated NC (No Connection) and is internally unbonded. As confirmed in Figure 6-4 and Table 6-1 of the SLVS184F datasheet, this pin must remain unconnected-no routing, termination, or grounding is permitted. Violating this requirement may compromise device reliability or thermal performance. The NC designation is specific to the DGN package; SOIC variants use Pin 6 for NC.

Can TPS3707-33DGN monitor a 12 V auxiliary supply?

Yes, TPS3707-33DGN can monitor a 12 V auxiliary supply using its PFI (Power-Fail Input) pin. The PFI threshold is fixed at 1.25 V ±0.05 V, so a resistor divider (e.g., 910 kΩ + 120 kΩ as shown in Figure 9-1) scales the 12 V rail to ~1.25 V at PFI. Section 9.2.2 provides the design equation, and Section 7.5 specifies PFI input current ≤±1 µA-ensuring minimal loading. This enables low-battery or auxiliary supply failure detection independent of the 3.3 V V_DD rail.

How does the dual-reset output (RESET and RESET) benefit system design?

The dual-reset outputs of TPS3707-33DGN-active-low open-drain RESET and active-high push-pull RESET-allow simultaneous interfacing with multiple reset domains without external logic. For example, RESET can drive an NMI input on an MSP430, while RESET directly resets a companion ASIC or FPGA. This eliminates level shifters, inverters, or dual-supervisor ICs, reducing BOM cost, PCB area, and qualification complexity. The architecture is validated in TI's typical MSP430 application (Figure 9-1).