STMicroelectronics ST1PS01HJR

Overview

ST1PS01HJR 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 (0.625 V to 1.05 V) via D0/D1 pins and features Power Good open-drain output, 100% duty cycle operation, and integrated soft-start - optimized for single-cell Li-Ion wearable sensors and energy-harvesting nodes.

For engineers reviewing the ST1PS01HJR datasheet, ST1PS01HJR pinout, ST1PS01HJR application, or ST1PS01HJR equivalent, key selection criteria include ultra-low IQ performance, flip-chip thermal resistance (60 °C/W), dynamic VOUT scaling capability, and compatibility with 2.2 µH inductors and 0603 ceramic capacitors in space-constrained PCBs.

Technical Context

The ST1PS01HJR employs peak current control (PCC) architecture with seamless PFM/PWM mode transition to maintain high efficiency across microampere to 400 mA loads. Its hysteretic comparator monitors coil ripple current, enabling constant ripple regulation independent of load or input voltage.

It integrates UVLO (1.57 V falling threshold), output discharge MOSFET (30 Ω on-resistance), and 100% duty cycle mode activated when VIN approaches selected VOUT - bypassing switching to minimize dropout loss. The Power Good flag asserts high-impedance when VOUT reaches ≥97.5% of target.

Key Specifications

Pinout & Package

ST1PS01HJR uses the Flip-Chip8 package (1.14 mm × 1.44 mm, 0.55 mm height), designed for ultra-thin applications with direct die-to-PCB interconnect and superior thermal performance over QFN.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS62840YKAR and ADP5302ACBZ-1-R7, ST1PS01HJR uniquely combines nano-IQ, dynamic digital VOUT selection, PGOOD, and 100% duty cycle - making it optimal for space- and energy-constrained systems requiring adaptive rail management.

Availability

ST1PS01HJR is available at Aetrix Electronics and suitable for wearable health monitors, energy-harvesting wireless sensors, and smart sport bands requiring stable component supply with guaranteed long-term manufacturability.

Supply support for ST1PS01HJR 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, specializing in power management, microcontrollers, and analog/mixed-signal ICs for industrial, automotive, and consumer markets.

The ST1PS01 series targets ultra-low-power portable electronics - engineered specifically for applications where PCB thickness, battery lifetime, and dynamic voltage scalability outweigh cost or feature breadth.

FAQ

What is the minimum input voltage required for ST1PS01HJR to regulate 0.625 V output?

The device enters 100% duty cycle mode when VIN drops near VOUT + 300 mV, so regulation of 0.625 V requires VIN ≥ 0.925 V. However, functional startup and UVLO release occur only above 1.57 V (falling) - thus stable regulation begins at VIN ≥ 1.57 V, with 100% mode extending usability down to 0.925 V once enabled.

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

Yes - D0 and D1 support real-time VOUT reconfiguration (e.g., 0.625 V ↔ 0.90 V) during active operation, provided VIN ≥ selected VOUT + 300 mV. Transitions settle within microseconds, with output ripple <10 mV under 5 mA load, as verified in Figure 10 of DS12799 Rev 6.

Does ST1PS01HJR require an external pull-up on 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, PGOOD remains floating and cannot indicate proper regulation status to host controllers or sequencers.

How does the 100% duty cycle mode affect output voltage accuracy?

In 100% mode, VOUT = VIN − (I_OUT × R_DS(on)) − I_OUT × R_INDUCTOR, so accuracy depends on MOSFET on-resistance (0.38 Ω typ.) and inductor DCR. At 100 mA load, dropout is ~38 mV - significantly less than standard LDOs, but unregulated relative to target VOUT.