My Inquiry
My Account
Texas Instruments TPS3305-18D
- Part No.:
- TPS3305-18D
- Manufacturer:
- Texas Instruments
- Category:
- Supervisors
- Package:
- 8-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
TPS3305-18D.pdf
- Description:
- IC SUPERVISOR 2 CHANNEL 8SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:1,013
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
TPS3305-18D from Texas Instruments is a dual-voltage supervisor IC for DSP and processor-based systems, monitoring 3.3V I/O and 1.8V core supplies with 2.93V and 1.68V thresholds respectively, featuring 200ms power-on reset delay, watchdog timer (1.6s timeout), and operation from 2.7V to 6V supply. It supports industrial temperature range (–40°C to +85°C) and delivers <40µA quiescent current.
For engineers reviewing the TPS3305-18D datasheet, TPS3305-18D pinout, TPS3305-18D application, or TPS3305-18D equivalent, this page provides verified specifications, SOIC-8 package details, dual-supply supervision logic, watchdog timing behavior, and validated alternative parts for system-level reset architecture design.
Technical Context
The TPS3305-18D implements independent voltage monitoring on SENSE1 (3.3V nominal, 2.93V threshold) and SENSE2 (1.8V nominal, 1.68V threshold), each with 30mV hysteresis. Its internal oscillator drives both the 200ms reset delay timer and the 1.6s watchdog timeout circuit.
RESET assertion occurs on any of three conditions: SENSE1 or SENSE2 falling below VIT−, MR pin pulled low, or WDI pin inactive for >1.6s. RESET deassertion requires both SENSE inputs above VIT+ and completion of the factory-programmed 200ms delay.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Supervised voltages | 3.3V I/O rail (SENSE1) and 1.8V core rail (SENSE2) |
| Voltage thresholds | SENSE1: 2.93V (±30mV hysteresis); SENSE2: 1.68V (±30mV hysteresis) |
| Reset delay time | 200ms typ - ensures stable power-up before processor release |
| Watchdog timeout | 1.6s typ - detects firmware lockup without external capacitor |
| Supply current | 40µA max - enables battery-backed or ultra-low-power applications |
| Operating voltage | 2.7V to 6V - compatible with 3.3V and 5V system rails |
| Temperature range | –40°C to +85°C - qualified for industrial environments |
Pinout & Package
TPS3305-18D is housed in an 8-pin SOIC (D) package (5.05mm × 3.95mm, 1.75mm max height), RoHS-compliant with NiPdAu lead finish and MSL Level-1 rating.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| SENSE1 | Voltage monitor input 1 | Monitors 3.3V I/O supply; asserts RESET if <2.93V |
| SENSE2 | Voltage monitor input 2 | Monitors 1.8V core supply; asserts RESET if <1.68V |
| WDI | Watchdog timer input | Must toggle every ≤1.6s; failure triggers RESET |
| GND | Ground reference | Common return path for all analog and digital functions |
| VDD | Supply input | Powers internal circuitry; functional down to 1.1V for defined RESET output |
| MR | Manual reset input | Active-low; forces RESET when pulled low |
| RESET | Active-low reset output | Drives microcontroller /DSP reset pin directly (IOL = 5mA) |
| RESET | Active-high reset output | Complementary signal for logic-level compatibility with diverse host interfaces |
Key Features
| Feature | Design Value |
|---|---|
| Dual independent voltage monitoring | Simultaneous supervision of 3.3V I/O and 1.8V core rails eliminates need for two discrete supervisors |
| Factory-programmed 200ms reset delay | No external capacitor required - reduces BOM count and layout area |
| Integrated watchdog timer | 1.6s timeout with no external components - simplifies firmware recovery design |
| Guaranteed RESET output down to VDD = 1.1V | Ensures deterministic reset behavior during brownout or battery discharge |
| Low 40µA supply current | Enables use in always-on subsystems and portable equipment with extended battery life |
Applications
| Processor Power Sequencing | DSP-Based Signal Processing |
|---|---|
Use Scenario: Coordinating startup of dual-rail processors where I/O voltage must stabilize before core voltage release. IC Role / Device Role / Timing Role: Dual-supply supervisor enforcing 200ms delay between valid SENSE1 and SENSE2 detection before releasing RESET. Use Value: Prevents race conditions during boot by ensuring 3.3V I/O rail is fully settled before enabling 1.8V core logic. | Use Scenario: Monitoring TI C6000-series DSPs requiring separate 3.3V I/O and 1.8V core supplies. IC Role / Device Role / Timing Role: Real-time voltage fault detection on both rails plus watchdog supervision of DSP firmware execution. Use Value: Eliminates need for external RC timing networks while providing fail-safe reset under undervoltage or software hang. |
| Industrial Control Unit | Portable Communication Module |
Use Scenario: Ensuring reliable boot in PLC I/O modules exposed to wide ambient temperature swings. IC Role / Device Role / Timing Role: Supervising 3.3V FPGA configuration voltage and 1.8V transceiver core voltage across –40°C to +85°C. Use Value: Temperature-compensated thresholds maintain ±3% accuracy over full operating range, preventing spurious resets. | Use Scenario: Battery-powered LTE modem requiring low-quiescent supervision during sleep mode. IC Role / Device Role / Timing Role: Micropower (40µA) dual-rail monitor with watchdog that wakes host on timeout event. Use Value: Extends battery runtime by minimizing standby current while retaining full fault coverage. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar dual-supply supervision applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TPS3305-18DGN | HVSSOP-8 package (3mm × 3mm, 1.1mm height) vs SOIC-8; identical electrical specs | Better thermal performance and smaller footprint; requires different PCB land pattern | Select for space-constrained or thermally demanding designs where SOIC-8 layout area is prohibitive |
| TPS3808G18 | Single-supply supervisor (1.8V only); no SENSE1 input or dual-rail capability | Lacks 3.3V I/O monitoring - cannot replace dual-monitor function without adding second device | Use only when supervising a single 1.8V rail; not a functional substitute for TPS3305-18D's dual-input architecture |
Compared with TPS3305-18DGN, the TPS3305-18D offers identical supervision functionality in a larger, through-hole-compatible SOIC package ideal for prototyping and legacy layouts; compared with TPS3808G18, it provides essential dual-rail monitoring unattainable with single-channel alternatives.
Availability
TPS3305-18D is available at Aetrix Electronics and suitable for industrial control units, DSP-based signal processing systems, and portable communication modules requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for TPS3305-18D 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 with emphasis on reliability, precision, and energy efficiency.
The TPS3305 family was designed specifically for dual-rail DSP and microprocessor systems requiring coordinated supervision of I/O and core supplies - addressing timing-critical boot sequencing and watchdog safety requirements in industrial and communications equipment.
FAQ
What is the exact voltage threshold for SENSE2 on the TPS3305-18D?
The TPS3305-18D has a nominal SENSE2 threshold of 1.68V, with guaranteed limits of 1.64V (min) and 1.72V (max) at TA = 0°C to +85°C. Over the full industrial temperature range (–40°C to +85°C), the threshold remains within 1.64V to 1.73V. This precisely matches the 1.8V core supply it monitors, providing ~7% headroom for ripple and tolerance.
Does the TPS3305-18D require external capacitors for reset timing?
No, the TPS3305-18D does not require external capacitors for its 200ms power-on reset delay or 1.6s watchdog timeout - both timers are factory-programmed and internally generated. A 0.1µF ceramic bypass capacitor is recommended at VDD/GND for noise immunity, but no timing capacitors are needed, reducing bill-of-materials count and PCB area.
Can the TPS3305-18D supervise a 5V supply instead of 3.3V on SENSE1?
No - the TPS3305-18D is factory-configured for 3.3V I/O (SENSE1 threshold = 2.93V) and 1.8V core (SENSE2 threshold = 1.68V). For 5V supervision, TI specifies the TPS3305-33 variant (SENSE1 threshold = 4.55V). Using TPS3305-18D on 5V would cause immediate RESET assertion since 5V exceeds the 2.93V threshold.
What is the maximum load the RESET output of the TPS3305-18D can drive?
The active-low RESET output of the TPS3305-18D supports a maximum sink current (IOL) of 5mA at VOL ≤ 0.4V (VDD = 3.3V). This is sufficient to directly drive most microcontroller reset inputs, FPGA configuration pins, or logic gates without external buffering. Exceeding 5mA may degrade VOL and compromise noise margin.
Is the TPS3305-18D pin-compatible with other members of the TPS3305 family?
Yes - all TPS3305-x variants (e.g., TPS3305-25D, TPS3305-33D) share identical SOIC-8 pinouts and terminal functions. Only the internal voltage thresholds differ. This allows drop-in replacement across variants when changing supervised rail voltages, provided the PCB layout accommodates the same SOIC-8 footprint and thermal constraints.
TPS3305-18D Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- 8-SOIC (0.154", 3.90mm Width)
- 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-SOIC
TPS3305-18D FAQ
1.How can I place an order for TPS3305-18D through Aetrix?
Please submit a Request for Quotation (RFQ) for TPS3305-18D 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 TPS3305-18D reliable?
The price and inventory of TPS3305-18D are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TPS3305-18D is usually 5 days.
3.What payment methods are accepted for TPS3305-18D?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TPS3305-18D transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TPS3305-18D?
TPS3305-18D orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TPS3305-18D 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 TPS3305-18D?
For technical support, including TPS3305-18D datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TPS3305-18D requirements.
6.How does Aetrix verify that TPS3305-18D is sourced from the original manufacturer or authorized distributors?
All TPS3305-18D 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 TPS3305-18D meets industry standards.
7.What is the process for return or replacement of TPS3305-18D?
All TPS3305-18D units undergo pre-shipment inspection (PSI). If there is an issue with TPS3305-18D, 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 TPS3305-18D part is unused and in its original packaging.
Return procedure for TPS3305-18D:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
TPS3305-18D Tags
-
MIC826SYMT-TR
Microchip Technology
-
APX803S-31SA-7
Diodes Incorporated
-
APX803L20-29SA-7
Diodes Incorporated
-
TPS3828-33DBVR
Texas Instruments
-
V6340RSP3B+
EM Microelectronic
-
EM6325CXSP5B-2.9+
EM Microelectronic
-
MCP120T-300I/TT
Microchip Technology
-
MCP130T-315I/TT
Microchip Technology
-
MCP120T-475I/TT
Microchip Technology
-
MCP111T-300E/TT
Microchip Technology
-
MCP120T-315I/TT
Microchip Technology
-
MCP809T-315I/TT
Microchip Technology
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
