STMicroelectronics ST1PS01FJR

Overview

ST1PS01FJR from STMicroelectronics is a nano-quiescent synchronous step-down DC-DC converter in Flip-Chip8 package, delivering up to 400 mA output current with 500 nA quiescent current at 3.6 V input and ±1.5% output voltage accuracy. It supports dynamic digital voltage selection (1.05 V / 1.25 V / 1.35 V / 1.55 V) via D0/D1 pins and features Power Good open-drain output, 100% duty cycle operation, and embedded soft-start. It targets ultra-low-power wearable and energy-harvesting systems powered by single-cell Li-Ion batteries.

For engineers reviewing the ST1PS01FJR datasheet, ST1PS01FJR pinout, ST1PS01FJR application, or ST1PS01FJR equivalent, key selection criteria include nano-quiescent current performance, dynamic VOUT selection capability, PGOOD flag timing behavior, and compatibility with 2.2 µH inductors and 0603 ceramic capacitors in space-constrained PCB layouts.

Technical Context

The ST1PS01FJR employs peak current control (PCC) architecture with seamless PFM/PWM mode transition to maintain high efficiency across load ranges from 100 µA to 400 mA. Its hysteretic comparator monitors coil ripple current directly, enabling stable regulation without external compensation components.

It integrates an internal 100% duty-cycle path activated when VIN approaches selected VOUT, bypassing switching to minimize dropout loss. The device also embeds fast output discharge (30 Ω on-resistance), UVLO with 1.57 V falling threshold and 65 mV hysteresis, and fixed 1.7 ms startup delay under nominal conditions.

Key Specifications

Pinout & Package

ST1PS01FJR uses the Flip-Chip8 package (1.14 mm × 1.44 mm, 0.55 mm height), optimized for minimal PCB footprint and thermal resistance (R_thJA = 60 °C/W). The die-up configuration places bumps on the active side for direct mounting onto substrate.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar nano-quiescent buck converter applications.

Compared with TPS62840YKAR and ADP5302ACBZ-1-R7, ST1PS01FJR uniquely combines nano-quiescent operation, digital VOUT selection, PGOOD, and Flip-Chip8 packaging - enabling lowest component count and smallest area for multi-voltage, battery-critical IoT endpoints.

Availability

ST1PS01FJR is available at Aetrix Electronics and suitable for wearable sensors, BLE nodes, and energy-harvesting transmitters requiring stable component supply with guaranteed long-term manufacturability and consistent parametric performance.

Supply support for ST1PS01FJR 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, sensors, and analog devices for industrial, automotive, and consumer markets.

The ST1PS01 series was developed specifically for ultra-low-power portable electronics, emphasizing nano-quiescent current, minimal external component count, and sub-2 mm² packaging to enable next-generation wearables and maintenance-free wireless sensors.

FAQ

What is the minimum input voltage required to sustain regulation at 1.55 V output?

The ST1PS01FJR enters 100% duty-cycle mode when VIN drops to VOUT + 300 mV (i.e., 1.85 V), maintaining regulation until VIN falls below the UVLO falling threshold of 1.57 V. Below 1.57 V, the device shuts down completely and disables SW switching.

Can D0 and D1 pins be changed dynamically during operation without disrupting output?

Yes - D0 and D1 support real-time voltage scaling. The output transitions smoothly between 1.05 V, 1.25 V, 1.35 V, and 1.55 V as long as VIN remains ≥ selected VOUT + 300 mV; no restart or glitch occurs, and regulation resumes within 100 µs after change.

Is an external pull-up resistor required for the PGOOD pin?

Yes - PGOOD is an open-drain output and requires an external pull-up resistor (typically 1 MΩ to VIN) to generate a valid logic-high signal. Without it, the pin remains high-impedance and cannot indicate "power good" to host logic or PMIC sequencers.

How does the ST1PS01FJR handle short-circuit conditions on the output?

Under sustained short-circuit, the high-side MOSFET current limit (500–1150 mA) triggers shutdown after soft-start period. The device holds VOUT low until EN is cycled low-then-high; output discharge (30 Ω) actively pulls VOUT to GND during disable to prevent backfeed.