STMicroelectronics ST1PS02C1QTR

Overview

ST1PS02C1QTR from STMicroelectronics is a nano-quiescent (500 nA), synchronous step-down DC-DC converter in TQFN12 package, delivering up to 400 mA output current with 1.8–5.5 V input range and digitally selectable 2.6–3.3 V output (via D0/D1/D2 pins). It integrates Power Good flag, auxiliary load switch (Vout2), and 100% duty cycle operation for ultra-low-power wearable and energy-harvesting systems.

For engineers reviewing the ST1PS02C1QTR datasheet, ST1PS02C1QTR pinout, ST1PS02C1QTR application, or ST1PS02C1QTR equivalent, this device supports dynamic voltage scaling, sub-µA shutdown current (10 nA typ.), ±1.5% output accuracy at 25 °C, and seamless PFM/PWM mode transition - critical for battery lifetime optimization in compact Li-ion-powered sensors.

Technical Context

The ST1PS02C1QTR employs peak current control (PCC) architecture with hysteretic switching, enabling stable regulation down to 10 µA loads while maintaining high efficiency (92% @ 10 mA, VIN=3.6 V, VOUT=2.5 V). Its 100% duty cycle mode directly connects VIN to VOUT when input approaches output voltage, minimizing dropout loss.

It features integrated soft-start (1.7 ms typical), programmable current limit via CL pin (default 850 mA typ., adjustable to 250 mA with external resistor), and dual regulated outputs: main VOUT (2.6–3.3 V) and auxiliary Vout2 (same rail, 100 mA max, RAUX = 0.75 Ω typ.). The PGOOD open-drain flag asserts when VOUT reaches ≥97.5% of target.

Key Specifications

Pinout & Package

TQFN12 (2.0 mm × 1.7 mm × 0.55 mm) thermally enhanced plastic package with exposed thermal pad; RoHS-compliant, ECOPACK2 certified.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous step-down converter applications.

Compared with TPS62840YKAR and ADP5302ACBZ-3.3-R7, ST1PS02C1QTR uniquely combines nano-IQ, digital voltage selection, auxiliary load switch, and 100% duty cycle - enabling adaptive power architectures unachievable with fixed-output alternatives.

Availability

ST1PS02C1QTR is available at Aetrix Electronics and suitable for wearable electronics, wireless sensor networks, and portable medical devices requiring stable component supply with long-term lifecycle assurance.

Supply support for ST1PS02C1QTR 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing microcontrollers, power management ICs, and analog/mixed-signal solutions for industrial, automotive, and consumer markets.

The ST1PS02 series targets ultra-low-power portable electronics, specifically engineered to maximize battery life and minimize PCB area in space-constrained applications such as wearables and IoT edge nodes.

FAQ

What is the maximum supported inductor value for ST1PS02C1QTR?

The ST1PS02C1QTR is optimized for 2.2 µH inductors (0806/2016 size) as specified in the application schematic and electrical characteristics. While higher values may function, they reduce switching frequency, increase output ripple, and degrade light-load efficiency due to PCC loop dynamics - ST recommends strict adherence to 2.2 µH for guaranteed performance across 10 µA–400 mA loads.

Can D0/D1/D2 pins be left unconnected if a fixed output voltage is required?

No - D0, D1, and D2 pins must be actively driven to defined logic levels (high or low) and cannot be left floating. For fixed 3.0 V output (D2=1, D1=0, D0=0), these pins should be tied to VIN or GND via appropriate pull-up/down resistors. Floating pins cause undefined VOUT and potential regulation failure per functional pin description in DS13206 Rev 5 page 4.

How does the CL pin affect current limiting during 100% duty cycle operation?

During 100% duty cycle (VIN ≈ VOUT), the ST1PS02C1QTR disables switching and relies on high-side MOSFET conduction. If overload occurs in this mode, the device shuts down VOUT until EN is cycled - the CL pin setting has no effect in 100% mode. CL only governs current limit during active PWM/PFM switching operation (DS13206 Rev 5 page 10).

Is the Vout2 auxiliary output internally discharged when AUX is low?

Yes - when AUX is driven low, the internal discharge MOSFET for Vout2 activates, discharging the output capacitor through a 30–50 Ω path (Rdisc2). This ensures rapid rail collapse for safe subsystem power-down, as confirmed in Table 6 (Rdisc2 parameter) and Section 7.3 of DS13206 Rev 5.