Texas Instruments TPS7133QP

Overview

TPS7133QP from Texas Instruments is a 3.3-V fixed-output, micropower low-dropout (LDO) voltage regulator featuring PMOS pass architecture, 3.23 V to 3.37 V output voltage tolerance over –40°C to 125°C, 285 µA typical quiescent current independent of load, 0.5 µA max sleep-state current, and integrated power-good (PG) status output. It delivers up to 500 mA output current and targets battery-powered portable electronics requiring stable low-noise supply with ultra-low standby consumption.

For engineers reviewing the TPS7133QP datasheet, TPS7133QP pinout, TPS7133QP application, or TPS7133QP equivalent, key selection criteria include dropout performance at 100 mA (max 60 mV), PG threshold accuracy (2.868 V to 3.0 V), thermal shutdown at 165°C, SENSE-pin configuration for remote sensing, and compatibility with 10 µF ceramic output capacitors in space-constrained designs.

Technical Context

The TPS7133QP uses a PMOS pass transistor instead of conventional PNP, enabling dropout voltage directly proportional to output current (e.g., 47 mV typ at 100 mA, 235 mV typ at 500 mA) and eliminating load-dependent quiescent current drift. Its internal 1.178-V reference feeds a precision error amplifier driving the gate of the PMOS element.

Power-good logic monitors regulated output via the SENSE pin (tied to OUT in standard configuration), asserting PG low when VO drops below 2.868 V (–40°C to 125°C), with 35 mV hysteresis. Enable (EN) input supports TTL-compatible control, entering sleep mode at EN = VI with ≤2 µA total input current across temperature.

Key Specifications

Pinout & Package

TPS7133QP is supplied in an 8-pin plastic DIP (PDIP) package with 0.300-inch body width and through-hole mounting. Pin 1 is located at the left end of the top row when viewed from the top with the notch or dot oriented left.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LDO voltage regulator applications.

Compared with TPS7133QP, TPS7333QP omits power-good signaling and offers weaker sleep performance, while LP2985AIM5-3.3/NOPB trades output current and dropout for smaller size - making TPS7133QP optimal for 3.3-V systems needing robust monitoring, 500 mA drive, and <0.5 µA storage current.

Availability

TPS7133QP is available at Aetrix Electronics and suitable for portable medical sensors, industrial data loggers, automotive body control modules, and smart metering subsystems requiring stable component supply with guaranteed long-term manufacturability.

Supply support for TPS7133QP 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 headquartered in Dallas, Texas, specializing in analog and embedded processing technologies with broad industrial, automotive, and consumer market reach.

The TPS71xx family was designed specifically for micropower, low-dropout regulation in battery-critical applications - emphasizing ultra-low quiescent current, precise fixed-voltage outputs, and integrated power supervision.

FAQ

What is the minimum input voltage required for TPS7133QP to maintain regulation at 500 mA output?

The minimum input voltage for TPS7133QP at 500 mA is calculated as VO(max) + VDO(max). With VO(max) = 3.37 V and VDO(max) = 400 mV (–40°C to 125°C), VI(min) = 3.77 V. This matches the datasheet's recommended minimum input of 3.77 V, ensuring regulation across temperature and load extremes. The TPS7133QP maintains this margin using its PMOS pass element.

Can the SENSE pin of TPS7133QP be left unconnected or tied to GND?

No - the SENSE pin of TPS7133QP must be connected to the OUT pin (or to the load side of output trace for remote sensing) as specified in the datasheet. Leaving it floating or grounding it will cause regulation failure and potential output overvoltage. For standard operation, tie SENSE directly to OUT near the device; for remote sensing, route SENSE separately to the load point to compensate for PCB trace drop.

Does TPS7133QP require an external capacitor on the EN pin for noise immunity?

TPS7133QP does not specify or require an external capacitor on the EN pin. Its EN input has built-in hysteresis (50 mV) and operates reliably with clean TTL-level signals. However, if routing EN across noisy environments (e.g., near switching regulators), a 100 pF ceramic capacitor to GND at the EN pin can suppress fast transients without affecting response time - consistent with layout guidance in the SLVS092G datasheet.

How does the power-good (PG) output behave during startup and shutdown of TPS7133QP?

During startup, PG remains low until VO reaches ≥2.868 V and stabilizes; it then transitions high after ~10 µs delay. During shutdown (EN high), PG goes open-drain low within 1 µs of VO falling below 2.868 V. PG does not assert during thermal shutdown - it only reflects output voltage integrity. This behavior allows TPS7133QP to serve as both power supervisor and reset generator in resource-constrained designs.

Is TPS7133QP compatible with ceramic output capacitors, and what is the minimum recommended value?

Yes, TPS7133QP is fully compatible with ceramic output capacitors. The datasheet specifies stability with ≥10 µF X7R or X5R ceramics (ESR < 1 Ω), and recommends 10 µF as the minimum for full-load transient response and ripple suppression. Using less than 10 µF may cause instability or excessive overshoot during load steps - verified in Figure 2 and Application Information section of SLVS092G.