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Texas Instruments TPS3305-18DGN
- Part No.:
- TPS3305-18DGN
- Manufacturer:
- Texas Instruments
- Category:
- Supervisors
- Package:
- 8-TSSOP, 8-MSOP (0.118", 3.00mm Width) Exposed Pad
- Datasheet:
-
TPS3305-18DGN.pdf
- Description:
- IC SUPERVISOR 2 CHANNEL 8MSOP
- Quantity:
- Payment:
- Shipping:
Inventory:3,168
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Product details
Overview
TPS3305-18DGN from Texas Instruments is a dual-voltage supervisor IC for DSP and processor-based systems, monitoring 3.3 V (SENSE1) and 1.8 V (SENSE2) rails with factory-programmed 200 ms reset delay, watchdog timeout of 1.6 s typ, and supply current of 40 µA. It provides active-low and active-high RESET outputs and operates from 2.7 V to 6 V over –40°C to +85°C.
For engineers reviewing the TPS3305-18DGN datasheet, TPS3305-18DGN pinout, TPS3305-18DGN application, or TPS3305-18DGN equivalent, key selection criteria include dual-rail threshold accuracy (2.93 V / 1.68 V), hysteresis (30 mV typ), MR/WDI timing compatibility, and HVSSOP-8 thermal performance in space-constrained embedded power sequencing.
Technical Context
The TPS3305-18DGN implements two independent voltage sense comparators with temperature-compensated 1.25 V reference, each feeding a logic-controlled reset generator with fixed 200 ms deassertion delay after both SENSE inputs exceed their thresholds. Its watchdog circuit monitors WDI toggling and asserts RESET if no transition occurs within 1.6 s.
Reset assertion is triggered by any single event: SENSE1 or SENSE2 falling below VIT– (1.64 V / 2.86 V min), MR low, or WDI timeout. The device supports simultaneous core/I/O rail supervision in DSP systems and features defined RESET output down to VDD ≥1.1 V.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Supervised Voltages | SENSE1 = 3.3 V nominal (VIT+ = 2.93 V typ); SENSE2 = 1.8 V nominal (VIT+ = 1.68 V typ) |
| Reset Delay Time | 200 ms typ after both SENSE inputs recover - eliminates need for external capacitor and ensures stable system boot |
| Watchdog Timeout | 1.6 s typ - detects firmware lockup without requiring external timing components |
| Supply Current | 40 µA max - enables use in battery-powered or ultra-low-power systems |
| Operating Voltage Range | 2.7 V to 6 V - supports wide input rail flexibility including 3.3 V, 5 V, and intermediate supplies |
| Temperature Range | –40°C to +85°C - qualified for industrial and automotive under-hood environments |
| Output Types | Active-low RESET and active-high RESET - simplifies interface to diverse host logic families |
Pinout & Package
HVSSOP-8 (DGN) package: 3 mm × 3 mm, 0.65 mm pitch, 1.1 mm max height, exposed thermal pad for enhanced thermal dissipation in high-density PCB layouts.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| SENSE1 (Pin 1) | Voltage monitor input 1 | Monitors 3.3 V rail; asserts RESET when voltage falls below 2.93 V (typ) with 30 mV hysteresis |
| SENSE2 (Pin 2) | Voltage monitor input 2 | Monitors 1.8 V core rail; threshold = 1.68 V (typ), hysteresis = 30 mV |
| WDI (Pin 3) | Watchdog timer input | Requires toggling every ≤1.6 s; failure triggers immediate RESET assertion |
| GND (Pin 4) | Ground reference | Common return path for all internal circuits and output drivers |
| RESET (Pin 5) | Active-low reset output | Open-drain compatible; sinks up to 5 mA; asserted low during fault or reset delay |
| RESET (Pin 6) | Active-high reset output | Pull-up required externally; complements Pin 5 for direct CMOS/TTL interface |
| MR (Pin 7) | Manual reset input | Active-low; forces RESET assertion when pulled low, overriding all other conditions |
| VDD (Pin 8) | Supply voltage input | Accepts 2.7–6 V; powers internal reference, comparators, and logic; RESET defined down to 1.1 V |
Key Features
| Feature | Design Value |
|---|---|
| Dual independent voltage supervision | Simultaneous monitoring of I/O (3.3 V) and core (1.8 V) rails avoids separate supervisors and reduces BOM count |
| Factory-programmed 200 ms reset delay | Eliminates external RC timing network, improves board-level reliability and layout simplicity |
| Integrated watchdog timer | 1.6 s timeout with dedicated WDI pin enables firmware health checking without external oscillator or counter |
| Low quiescent current (40 µA) | Minimizes standby power draw in always-on subsystems such as modem wake logic or sensor hubs |
| Defined RESET operation down to VDD = 1.1 V | Ensures predictable reset behavior during brownout or battery discharge scenarios before full supply collapse |
Applications
| Processor Power Sequencing | DSP-Based Communications Equipment |
|---|---|
Use Scenario: Coordinating startup of 3.3 V I/O and 1.8 V core supplies in ARM Cortex-A/M series SoCs. IC Role / Device Role / Timing Role: Dual-rail supervisor ensuring proper voltage order and hold time before releasing reset to CPU and peripherals. Use Value: Prevents latch-up or undefined state during asymmetric rail ramp-up; eliminates need for discrete RC networks per rail. | Use Scenario: Monitoring power integrity in baseband processors for 4G/LTE modems where core voltage must stabilize before RF initialization. IC Role / Device Role / Timing Role: Simultaneous SENSE1/SENSE2 supervision plus WDI-driven firmware watchdog for fail-safe recovery. Use Value: Guarantees deterministic boot sequence and enables automatic recovery from software hangs without host intervention. |
| Industrial PLC Controller | Notebook Embedded Controller (EC) |
Use Scenario: Supervising dual-supply FPGA configuration circuitry (3.3 V bank, 1.8 V core) in programmable logic controllers operating in harsh environments. IC Role / Device Role / Timing Role: Fault-detection node asserting hardware reset on undervoltage or watchdog timeout, interfacing directly with FPGA PROG_B and INIT_B pins. Use Value: Maintains functional safety compliance by ensuring FPGA reconfiguration only occurs after stable power; hysteresis prevents chatter near threshold. | Use Scenario: Managing power-good signaling and reset coordination between EC, PMIC, and main CPU in thin-and-light notebooks. IC Role / Device Role / Timing Role: Dual-threshold supervisor providing synchronized RESET# and RESET signals to EC and chipset while supporting MR override for thermal shutdown events. Use Value: Reduces EC firmware complexity by offloading voltage monitoring and timing-critical reset generation to hardware. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar dual-supply monitoring applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TPS3305-18DR | Same electrical specs; SOIC-8 (D) package (4.9 mm × 3.9 mm) vs HVSSOP-8 (3 mm × 3 mm); higher thermal resistance (1.37 W vs 2.14 W power rating at 25°C) | Preferred for through-hole prototyping or legacy board designs with SOIC footprints; less suitable for high-density portable devices | Select TPS3305-18DR when board space allows larger footprint and thermal budget permits lower power dissipation capability |
| MAX6816EUT+T | Single-supply supervisor (1.8 V only); no dual-sense capability; includes debounced pushbutton interface; 1.6 µA supply current; SC70-6 package | Applicable only for single-rail monitoring with manual reset support; lacks watchdog and second sense channel | Choose MAX6816EUT+T only for cost-sensitive, space-constrained applications needing basic 1.8 V supervision without dual-rail or watchdog functionality |
Compared with TPS3305-18DR and MAX6816EUT+T, the TPS3305-18DGN uniquely delivers dual-rail supervision, integrated watchdog, and HVSSOP-8 thermal efficiency in a single 3 mm × 3 mm footprint-making it optimal for modern DSP, FPGA, and SoC power sequencing where board area and multi-rail coordination are critical.
Availability
TPS3305-18DGN is available at Aetrix Electronics and suitable for industrial PLC controllers, notebook embedded controllers, DSP-based communications equipment, and FPGA power sequencing requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for TPS3305-18DGN 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, embedded processing, and power management technologies, with leadership in high-reliability industrial and automotive ICs.
The TPS3305 family is designed specifically for dual-rail power supervision in DSP and processor-based systems, addressing the need for coordinated core/I/O voltage monitoring, programmable reset timing, and integrated watchdog functionality in compact packages.
FAQ
What is the exact threshold voltage for SENSE2 on the TPS3305-18DGN?
The TPS3305-18DGN has a nominal SENSE2 threshold voltage of 1.68 V (typical), with a minimum of 1.64 V and maximum of 1.72 V over temperature (0°C to +85°C). At full industrial range (–40°C to +85°C), the specification tightens to 1.64 V to 1.73 V. This threshold is factory-trimmed and applies exclusively to the TPS3305-18DGN variant, not other members of the TPS3305 family.
Does the TPS3305-18DGN require an external capacitor for its reset delay function?
No, the TPS3305-18DGN does not require an external capacitor for its reset delay function. It features a factory-programmed 200 ms typical delay time that is internally generated and temperature-stable. This eliminates external timing components, reduces bill-of-materials count, and improves reliability compared to RC-based solutions. The TPS3305-18DGN achieves this using on-chip oscillator and counter circuitry calibrated during manufacturing.
Can the TPS3305-18DGN monitor voltages other than 3.3 V and 1.8 V?
The TPS3305-18DGN is specifically configured to supervise 3.3 V (SENSE1) and 1.8 V (SENSE2) rails, with fixed internal thresholds of 2.93 V (typ) and 1.68 V (typ), respectively. It cannot be reconfigured for other voltage levels. For different combinations, TI offers alternate variants: TPS3305-25 (3.3 V / 2.5 V) and TPS3305-33 (5.0 V / 3.3 V). The TPS3305-18DGN's thresholds are laser-trimmed and not user-adjustable.
What is the maximum watchdog timeout period supported by the TPS3305-18DGN?
The TPS3305-18DGN supports a typical watchdog timeout period of 1.6 s, with a minimum of 1.1 s and maximum of 2.3 s over temperature and supply voltage. This timeout is fixed and non-adjustable. If the WDI pin remains static beyond this window, the device asserts RESET regardless of SENSE input states. The TPS3305-18DGN requires a clean, monotonic edge on WDI - not a DC level - to reset the watchdog timer.
Is the TPS3305-18DGN pin-compatible with other devices in the TPS3305 family?
Yes, all TPS3305-xxDGN and TPS3305-xxD variants share identical pinouts across the family (e.g., TPS3305-18DGN, TPS3305-25DGN, TPS3305-33DGN). Pin 1 is SENSE1, Pin 2 is SENSE2, Pin 3 is WDI, etc. This allows drop-in replacement between voltage variants when changing system rail requirements - provided the new thresholds match the target supply voltages. The TPS3305-18DGN's pin mapping is fully consistent with the family datasheet.
TPS3305-18DGN Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- 8-TSSOP, 8-MSOP (0.118", 3.00mm Width) Exposed Pad
- Packaging:
- Tube
- Product Status:
- Active
- Programmable:
- Not Verified
- Type:
- Multi-Voltage Supervisor
- Number of Voltages Monitored:
- 2
- Voltage - Threshold:
- 1.68V, 2.93V
- Output:
- Push-Pull, Totem Pole
- Reset:
- Active High/Active Low
- Reset Timeout:
- 140ms Minimum
- Operating Temperature:
- -40°C ~ 85°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-HVSSOP
TPS3305-18DGN FAQ
1.How can I place an order for TPS3305-18DGN through Aetrix?
Please submit a Request for Quotation (RFQ) for TPS3305-18DGN on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for TPS3305-18DGN reliable?
The price and inventory of TPS3305-18DGN are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TPS3305-18DGN is usually 5 days.
3.What payment methods are accepted for TPS3305-18DGN?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TPS3305-18DGN transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TPS3305-18DGN?
TPS3305-18DGN orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TPS3305-18DGN order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for TPS3305-18DGN?
For technical support, including TPS3305-18DGN datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TPS3305-18DGN requirements.
6.How does Aetrix verify that TPS3305-18DGN is sourced from the original manufacturer or authorized distributors?
All TPS3305-18DGN products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that TPS3305-18DGN meets industry standards.
7.What is the process for return or replacement of TPS3305-18DGN?
All TPS3305-18DGN units undergo pre-shipment inspection (PSI). If there is an issue with TPS3305-18DGN, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The TPS3305-18DGN part is unused and in its original packaging.
Return procedure for TPS3305-18DGN:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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