Texas Instruments TPS3600D25PW

Overview

TPS3600D25PW from Texas Instruments is a precision 2.5-V supply voltage supervisor IC with integrated watchdog timer, battery switchover control, and chip-enable gating. It monitors VDD/VOUT for brownout (VIT = 2.22 V typ), asserts active-low RESET with 100-ms delay, supports backup-battery operation up to 5.5 V, and delivers 300-mA output current in battery-backup mode. Used in portable battery-powered equipment requiring reliable power sequencing and fail-safe processor supervision.

For engineers reviewing the TPS3600D25PW datasheet, TPS3600D25PW pinout, TPS3600D25PW application, or TPS3600D25PW equivalent, key selection criteria include its 2.22-V threshold accuracy, 40-µA max supply current, 800-ms watchdog timeout, dual-supply switchover logic, and 14-pin TSSOP package with validated CEIN/CEOUT propagation delay of ≤3 ns at 5 V.

Technical Context

The TPS3600D25PW implements a dual-path power supervision architecture: one path monitors VOUT against a precision 2.22-V negative-going threshold (VIT) to trigger RESET, while a second path compares PFI to a fixed 1.15-V internal reference for independent power-fail detection. Its switchover logic uses V(SWN) = VIT + 1% to −3.2% to connect VBAT only when VOUT falls below threshold and VBAT > VDD.

Watchdog functionality relies on WDI edge-triggered reset with 0.8-s nominal timeout; BATTOK provides periodic (every 200 ms) battery voltage sampling via a 100-kΩ divider load and 25-µs measurement window; CE gating disables CEIN-to-CEOUT transmission during RESET assertion to prevent RAM corruption, with <3-ns propagation delay in enable mode at VDD = 5 V.

Key Specifications

Pinout & Package

TPS3600D25PW is housed in a 14-pin TSSOP (PW) package, 5.10 mm × 6.60 mm body size, RoHS-compliant, with Level-1 moisture sensitivity rating.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar supervisory circuit applications.

Compared with TPS3600D25PW, TPS3619D25PW omits battery switchover and watchdog-reducing complexity but eliminating failover capability-while MAX6326UT25+T trades all advanced features for sub-2-µA current draw, making it viable only in static-reset applications without runtime supervision needs.

Availability

TPS3600D25PW is available at Aetrix Electronics and suitable for portable battery-powered equipment, computer equipment, advanced modems, and point-of-sale terminals requiring stable component supply across industrial temperature ranges (−40°C to 85°C).

Supply support for TPS3600D25PW 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 power management, signal chain, and microcontrollers.

The TPS3600 family is designed for systems requiring robust power supervision, battery backup autonomy, and memory bus protection-targeting portable, telecom, and industrial equipment where uptime and data integrity are critical.

FAQ

What is the exact reset threshold voltage for TPS3600D25PW?

The TPS3600D25PW has a nominal negative-going input threshold voltage (VIT) of 2.22 V, with a guaranteed range of 2.17 V (min) to 2.27 V (max) over −40°C to 85°C. This value is factory-trimmed and applies specifically to the D25 variant, which is optimized for 2.5-V nominal supply systems. The threshold is sensed at VOUT and referenced to GND.

How does the battery switchover function work in TPS3600D25PW?

The TPS3600D25PW automatically connects VBAT to VOUT when VOUT falls below V(SWN) (VIT + 1% to +3.2%) and VBAT exceeds VDD. A 2-Ω internal switch enables this transition, supporting up to 300 mA. Switchover is deferred upon VDD recovery until VDD rises above V(SWP) or crosses VBAT, preventing oscillation during marginal conditions.

Can TPS3600D25PW monitor voltages other than VDD?

Yes-TPS3600D25PW includes a dedicated power-fail comparator with PFI input referenced to a 1.15-V internal bandgap. By connecting an external resistor divider to PFI, users can supervise any voltage ≥1.15 V (e.g., 12 V, −5 V, or 3.3 V auxiliary rails). PFO provides an active-low open-drain output indicating when the monitored voltage drops below threshold.

What is the purpose of the CEIN and CEOUT pins on TPS3600D25PW?

The CEIN and CEOUT pins implement chip-enable signal gating: CEIN passes through to CEOUT during normal operation, but the path is disabled during RESET assertion. This prevents erroneous memory writes during power-up/down transients. CEOUT is actively pulled to VOUT in disable mode, ensuring CMOS RAM remains deselected even if CEIN floats.

Does TPS3600D25PW require external components for basic operation?

Yes-TPS3600D25PW requires a 0.1-µF ceramic bypass capacitor between VOUT and GND for stable threshold reference, per datasheet Note 3. PFI and MR should be tied to GND if unused. MSWITCH must be grounded unless manual switchover is needed. No pull-ups or pull-downs are required on open-drain outputs (RESET, PFO, BATTOK) unless interfacing with higher-voltage logic.