Texas Instruments TPS7A7850PWPT

Overview

TPS7A7850PWPT from Texas Instruments is a 120-mA, non-isolated smart AC/DC linear voltage regulator with integrated 4:1 switched-capacitor stage and LDO output. It accepts ≥18 V_RMS AC input via cap-drop architecture, delivers fixed 5.0 V DC output at ±1% typical accuracy, supports full-bridge/half-bridge configurations, and enables <15 mW standby power in electricity meters and smoke detectors.

For engineers reviewing the TPS7A7850PWPT datasheet, TPS7A7850PWPT pinout, TPS7A7850PWPT application, or TPS7A7850PWPT equivalent, key selection criteria include AC-input compatibility (18–270 V_RMS), programmable power-fail detection threshold (1.17–1.42 V), open-drain PG/PF outputs, thermal shutdown (162°C), and HTSSOP-14 package constraints for magnetic-tamper-resistant designs.

Technical Context

The TPS7A7850PWPT integrates an actively clamped full/half-bridge rectifier, dual-stage switched-capacitor charge pump (SC1±, SC2±) that reduces rectified input voltage by 4×, and a precision LDO regulating VLDO_OUT to 5.0 V. Its UVLO_SCIN (17 V rising) and UVLO_LDO_IN (3.9 V rising) ensure staged startup under AC or DC supply modes.

Power-fail detection uses resistor-divided VSCIN on PFD pin with 110 mV hysteresis; PG and PF outputs are open-drain with 0.2 V low-level voltage at 500 µA load. The device operates across –40°C to +125°C junction temperature and achieves ≤3 mV output ripple at 10 mA load in full-bridge configuration.

Key Specifications

Pinout & Package

TPS7A7850PWPT is housed in a 5.0 mm × 6.5 mm HTSSOP-14 (PWP) package with exposed thermal pad connected to GND for optimal thermal dissipation (R_θJA = 48.0°C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar AC/DC linear regulator applications.

Compared with TPS7A7833PWPT, the TPS7A7850PWPT delivers 5.0 V for legacy 5 V peripherals without level-shifting; versus NCP1094DR2G, it integrates PFD/PG and active bridge control-reducing component count by ≥7 parts and eliminating layout-sensitive analog threshold design.

Availability

TPS7A7850PWPT is available at Aetrix Electronics and suitable for electricity metering, smoke detector design, thermostat development, and garage door control systems requiring stable component supply with long lifecycle assurance.

Supply support for TPS7A7850PWPT 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 specializing in analog, embedded processing, and power management technologies with over 50 years of innovation in high-reliability power solutions.

The TPS7A78 product line delivers smart AC/DC linear regulators targeting magnetic-tamper-resistant, low-standby-power applications in utility metering, building automation, and safety-critical sensing systems.

FAQ

What AC input voltage range does the TPS7A7850PWPT support?

The TPS7A7850PWPT supports 18–270 V_RMS AC input via external cap-drop capacitor and surge resistor. This range covers global mains voltages (100–240 VAC) and low-voltage HVAC transformers (24 VAC), validated per IEC 61000-4-8 for magnetic immunity in electricity meters.

How does the TPS7A7850PWPT achieve 15 mW standby power?

The TPS7A7850PWPT achieves 15 mW typical standby power through its 4:1 switched-capacitor stage, which reduces input current draw by 4× versus conventional cap-drop designs. Combined with active bridge clamping and optimized quiescent current (280 µA on SCIN), it minimizes losses during light-load or sleep-mode operation.

Can the TPS7A7850PWPT operate from a DC supply instead of AC?

Yes-the TPS7A7850PWPT supports DC-only operation by applying 17–23 V directly to the SCIN pin. In this mode, AC+ and AC– pins must be grounded, and the device bypasses the active bridge. This enables DC backup power in thermostats or garage door panels during AC outages.

What is the function of the SC1± and SC2± pins on the TPS7A7850PWPT?

The SC1± and SC2± pins form two independent switched-capacitor stages that together implement a 4:1 voltage reduction from SCIN to LDO_IN. SC1± handles coarse stepping; SC2± refines regulation. Each requires a 1–4.7 µF X5R capacitor (16 V for SC1, 10 V for SC2) placed within 2 mm of the pins for stable operation.

How do the PG and PF pins behave on the TPS7A7850PWPT?

PG is an open-drain power-good indicator that pulls low until VLDO_OUT exceeds 90.16% of 5.0 V (4.508 V), then releases to allow external pullup. PF pulls low when PFD voltage falls below 1.17 V, signaling imminent AC loss. Both require external pullup resistors (10–100 kΩ) to VLDO_IN or a shared DC rail.