My Inquiry
My Account
Texas Instruments TPS23861PW
- Part No.:
- TPS23861PW
- Manufacturer:
- Texas Instruments
- Category:
- Power Over Ethernet (PoE) Controllers
- Package:
- 28-TSSOP (0.173", 4.40mm Width)
- Datasheet:
-
TPS23861PW.pdf
- Description:
- IC POE CNTRL 4 CHANNEL 28TSSOP
- Quantity:
- Payment:
- Shipping:
Inventory:2,095
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
TPS23861PW from Texas Instruments is an IEEE 802.3at-compliant quad-port Power-over-Ethernet (PoE) Powered Device (PD) detection and classification controller with integrated gate drivers, Kelvin current sensing, and I²C interface. It supports automatic two-event classification for Type-2 PDs, features 255-mΩ sense resistor compatibility, operates across –40°C to 125°C junction temperature, and delivers precise port current/voltage monitoring via integrated 12-bit ADCs. It is used in Ethernet switches to safely power VoIP phones, IP cameras, and wireless access points.
For engineers reviewing the TPS23861PW datasheet, TPS23861PW pinout, TPS23861PW application, or TPS23861PW equivalent, key selection criteria include IEEE 802.3at compliance, quad-port autonomous operation, Kelvin-sensed current measurement accuracy (±2.5% over 50–770 mA), 400-ms TPON timing guarantee, and TSSOP-28 thermal performance (RθJA = 70.9°C/W).
Technical Context
The TPS23861PW implements a fully autonomous PoE PSE controller architecture with four independent port control channels, each featuring dual-stage detection (145–300 µA), 15.5–20.5 V classification voltage, and programmable ILIM/ICUT thresholds. Its internal logic enforces IEEE 802.3at TPON ≤400 ms and supports both automatic and semi-automatic (I²C-controlled) modes.
Kelvin sensing via KSENSA/KSENSB terminals enables accurate current measurement by eliminating PCB trace resistance error; the integrated 12-bit ADC provides 80–125 ms integration time per port with ±2.5% current reading accuracy and ±3.5% voltage reading accuracy across 44–57 V VPWR range.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| IEEE Standard | Complies with IEEE 802.3at (PoE+) for full four-port operation including two-event classification. |
| Operating Temp | Junction range –40°C to +125°C - enables deployment in industrial Ethernet switches and outdoor NVR enclosures. |
| VDD Supply | 3.3 V ±10% (3.0–3.6 V); draws ≤6 mA - compatible with standard logic LDOs and low-noise 3.3-V rails. |
| VPWR Range | 44–57 V analog supply - supports full PoE+ voltage tolerance with 25 V UVLO hysteresis. |
| Current Sensing | ±2.5% accuracy (50–770 mA) using 255-mΩ sense resistor and Kelvin inputs - eliminates trace-resistance error in high-current paths. |
| ADC Resolution | 12-bit conversion with 80–125 ms averaging per port - ensures stable current/voltage readings under dynamic load conditions. |
| TPON Timing | ≤400 ms guaranteed in both auto and semi-auto modes - meets IEEE 802.3at turn-on specification without external timing components. |
Pinout & Package
TSSOP-28 package (9.8 mm × 6.6 mm) with exposed thermal pad; optimized for two-layer PCB layout via logical pin grouping and separation of power (VPWR, DRAINn, GATEn) and digital (SCL, SDAI/SDAO, INT) domains.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| VDD | Digital supply input | 3.3-V logic rail; requires 0.1-µF bypass to DGND - powers internal logic, I²C interface, and ADC. |
| VPWR | Analog high-voltage supply | 48-V PoE bus input; bypassed to AGND - supplies gate drivers and sensing circuitry; UVLO threshold at 25–28 V for port de-assertion. |
| GATE1–GATE4 | Port MOSFET gate drivers | 12.5-V max open-drain outputs sinking up to 100 mA - directly drive external N-channel FETs with fast turn-off during fault events. |
| SEN1–SEN4 | Current-sense inputs | High-impedance inputs referenced to KSENSA/KSENSB - enable Kelvin connection to 22-Ω sense resistors for precision current measurement. |
| DRAIN1–DRAIN4 | Port output voltage monitor | High-Z inputs tied via 47-Ω resistors to port output - used for detection, classification, and powered-port voltage measurement. |
| SCL / SDAI / SDAO | I²C interface | Standard 3.3-V I²C bus (400-kHz capable); SDAI/SDAO are open-drain - enables real-time port status monitoring and configuration. |
| INT | Interrupt output | Open-drain active-low signal asserted when any interrupt flag (fault, class fail, overtemp) is set - reduces polling overhead in host MCU. |
| RESET | Hardware reset input | Active-low asynchronous reset; internally pulled up to VDD - allows system-level recovery without power cycle. |
Key Features
| Feature | Design Value |
|---|---|
| Quad-port IEEE 802.3at compliance | Full support for all four ports including two-event classification, 400-ms TPON, and 25.5-W per-port delivery - eliminates need for external protocol logic. |
| Kelvin current sensing | Dual Kelvin inputs (KSENSA/KSENSB) eliminate PCB trace resistance error - achieves ±2.5% current accuracy without calibration. |
| Autonomous operation mode | Ships preconfigured for automatic detection/classification/turn-on - no I²C initialization or external configuration required for basic PoE+ operation. |
| Thermally optimized TSSOP-28 | RθJA = 70.9°C/W with continuous backside GND plane - enables reliable 4-port operation at 85°C ambient without forced air. |
| Integrated 12-bit ADC | Simultaneous per-port voltage/current measurement with 80–125 ms integration - provides real-time telemetry for intelligent power management. |
Applications
| VoIP Phone Switching | IP Camera Surveillance |
|---|---|
|
Use Scenario: Enterprise Ethernet switch powering multiple VoIP desk phones with varying power classes (Class 0–4). IC Role / Device Role / Timing Role: TPS23861PW acts as the primary PSE controller managing detection, classification, and power application on all four ports; enforces 400-ms TPON and disconnects faulty ports within microseconds. Use Value: Enables single-chip quad-port PoE+ support with autonomous operation - reduces BOM count and firmware complexity versus discrete controller + microcontroller solutions. |
Use Scenario: Outdoor NVR system delivering 25.5 W to PTZ IP cameras over long cable runs with variable ambient temperature. IC Role / Device Role / Timing Role: TPS23861PW performs Kelvin-sensed current monitoring and thermal-aware port management; maintains stable power delivery across –40°C to 85°C ambient. Use Value: Achieves ±2.5% current accuracy without calibration - ensures consistent power budgeting and prevents overloading under temperature drift. |
| Wireless Access Point Hub | PoE Pass-Through Gateway |
|
Use Scenario: Residential gateway aggregating Wi-Fi 6 APs, each requiring up to 25.5 W and supporting LLDP-based power negotiation. IC Role / Device Role / Timing Role: TPS23861PW serves as the front-end PSE controller handling physical layer detection/classification; I²C interface feeds data to host MCU for higher-layer power management. Use Value: Supports semi-automatic mode with continuous I²C monitoring - enables dynamic power reallocation between ports based on AP load profiles. |
Use Scenario: Midspan PoE injector embedded in a fiber-to-the-home gateway, delivering power to downstream PoE switches. IC Role / Device Role / Timing Role: TPS23861PW manages four independent PoE+ ports with DC disconnection capability and robust short-circuit protection on each channel. Use Value: Fault isolation per port (GATEx disconnect on short) prevents cascade failure - improves system uptime in multi-tier PoE deployments. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar PoE PSE controller applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TPS23881RTQT | Octal-port 802.3bt (PoE++) controller with 90-W per port, integrated DC-DC controller, and enhanced thermal metrics (RθJA = 42.5°C/W). | Supports higher-power devices (e.g., PTZ cameras with heaters, thin clients) and requires additional magnetics/transformers for 802.3bt signature. | Select TPS23881RTQT when upgrading to PoE++ or needing >25.5 W/port; not drop-in due to pin count (40-QFN), voltage rails, and register map differences. |
| MAX5984AEUI+ | Quad-port 802.3af/at controller in 28-TSSOP; lacks Kelvin sensing, uses single-ended current sense; ±5% current accuracy; no integrated ADC. | Suitable for cost-sensitive 802.3at applications where ±2.5% accuracy and per-port telemetry are not required. | Choose MAX5984AEUI+ for legacy PoE+ designs prioritizing footprint compatibility over sensing precision; requires external ADC for monitoring. |
Compared with TPS23861PW, TPS23881RTQT offers higher power and newer standard support but demands more board space and design effort, while MAX5984AEUI+ reduces cost and complexity at the expense of measurement fidelity and autonomous feature depth.
Availability
TPS23861PW is available at Aetrix Electronics and suitable for Ethernet switches, surveillance NVRs, and residential gateways requiring stable component supply, long-term lifecycle assurance, and production-ready PoE+ controller solutions.
Supply support for TPS23861PW 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 ICs, with leadership in industrial, automotive, and communications infrastructure markets.
The TPS23861PW belongs to TI's Power-over-Ethernet PSE controller product line, designed specifically for compact, thermally efficient, and standards-compliant midspan and endpoint PoE+ systems targeting enterprise and surveillance infrastructure.
FAQ
What is the maximum number of PoE ports supported by the TPS23861PW?
The TPS23861PW is a dedicated quad-port IEEE 802.3at Power-over-Ethernet PSE controller, supporting exactly four independent PoE ports. Each port includes full detection, classification, power application, and fault management logic. It does not support expansion beyond four ports without external multiplexing or additional controllers.
Does the TPS23861PW require external microcontroller firmware to operate?
No - the TPS23861PW ships in Automatic Mode and performs full IEEE 802.3at detection, classification, and power application on all four ports without any I²C communication or external firmware. Optional I²C control is available for advanced monitoring and semi-automatic operation, but it is not required for basic PoE+ functionality.
What is the purpose of the KSENSA and KSENSB pins on the TPS23861PW?
KSENSA and KSENSB are Kelvin sensing reference terminals on the TPS23861PW that connect to the high-side and low-side nodes of external current-sense resistors. They eliminate voltage drop errors caused by PCB trace resistance, enabling ±2.5% current measurement accuracy across 50–770 mA per port - critical for reliable power budgeting and fault detection.
Can the TPS23861PW be used in PoE++ (IEEE 802.3bt) applications?
No - the TPS23861PW is certified only for IEEE 802.3at (PoE+) with up to 25.5 W per port. It does not support the higher power levels (up to 90 W), four-pair power delivery, or extended classification protocols defined in IEEE 802.3bt. For PoE++, TI recommends the TPS23881RTQT or TPS23882RTQT.
What thermal performance can be expected from the TPS23861PW in a two-layer PCB design?
In a standard two-layer PCB with continuous backside ground plane and proper copper pour, the TPS23861PW achieves RθJA = 70.9°C/W. At full 4-port operation with 25.5 W/port, junction temperature rise remains within spec up to 85°C ambient - validated in TI's reference layout (SLUSBX9I, Figure 10-2), confirming suitability for fanless industrial enclosures.
TPS23861PW Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- 28-TSSOP (0.173", 4.40mm Width)
- Packaging:
- Tube
- Product Status:
- Active
- Type:
- Controller (PSE)
- Number of Channels:
- 4
- Power - Max:
- 25.5 W
- Internal Switch(s):
- No
- Auxiliary Sense:
- No
- Standards:
- 802.3at (PoE+), 802.3af (PoE)
- Voltage - Supply:
- 44V ~ 57V
- Current - Supply:
- 3.5mA
- Operating Temperature:
- -40°C ~ 85°C
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 28-TSSOP
TPS23861PW FAQ
1.How can I place an order for TPS23861PW through Aetrix?
Please submit a Request for Quotation (RFQ) for TPS23861PW 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 TPS23861PW reliable?
The price and inventory of TPS23861PW are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TPS23861PW is usually 5 days.
3.What payment methods are accepted for TPS23861PW?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TPS23861PW transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TPS23861PW?
TPS23861PW orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TPS23861PW 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 TPS23861PW?
For technical support, including TPS23861PW datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TPS23861PW requirements.
6.How does Aetrix verify that TPS23861PW is sourced from the original manufacturer or authorized distributors?
All TPS23861PW 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 TPS23861PW meets industry standards.
7.What is the process for return or replacement of TPS23861PW?
All TPS23861PW units undergo pre-shipment inspection (PSI). If there is an issue with TPS23861PW, 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 TPS23861PW part is unused and in its original packaging.
Return procedure for TPS23861PW:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
TPS23861PW Tags
-
TPS2378DDAR
Texas Instruments
-
TPS23753APWR
Texas Instruments
-
TPS23756PWPR
Texas Instruments
-
TPS23750PWPR
Texas Instruments
-
MP8007GV-Z
Monolithic Power Systems Inc.
-
TPS23861PWR
Texas Instruments
-
TPS23753PWR
Texas Instruments
-
PD69201ILD-TR
Microchip Technology
-
SI3402-B-GM
Skyworks Solutions Inc.
-
SI3402-B-GMR
Skyworks Solutions Inc.
-
SI34071-A01-GMR
Skyworks Solutions Inc.
-
SI3404-A-GMR
Skyworks Solutions Inc.
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…
