Toshiba Semiconductor and Storage TCR3UM28A,LF

Overview

TCR3UM28A,LF from Toshiba Electronic Devices & Storage Corporation is a CMOS low-dropout linear regulator delivering fixed 2.8 V output at up to 300 mA, featuring ultra-low quiescent current (0.38 μA typ. at 2.8 V), 196 mV dropout at full load, and fast load transient response (±36/−51 mV). It serves as a power management IC in space-constrained portable systems requiring stable, low-noise voltage regulation.

For engineers reviewing the TCR3UM28A,LF datasheet, TCR3UM28A,LF pinout, TCR3UM28A,LF application, or TCR3UM28A,LF equivalent, this page provides verified electrical parameters, DFN4 package layout, thermal shutdown behavior, auto-discharge functionality, and design-critical capacitor compatibility (1 μF ceramic input/output).

Technical Context

The TCR3UM28A,LF integrates a PMOS pass transistor with internal control logic enabling on/off operation via the CONTROL pin, thermal shutdown at 158°C with 28°C hysteresis, and overcurrent protection triggering at 545 mA (typ.). Its architecture supports stable regulation with minimal external components due to inherent phase compensation for 1 μF ceramic capacitors.

It operates across −40°C to +85°C ambient temperature with input voltage range 1.5–5.5 V and maintains ±1.0% output accuracy for VOUT ≥ 1.8 V - directly applicable to the 2.8 V output of TCR3UM28A,LF. The device implements an inrush current protection circuit and internal pull-down between CONTROL and GND to ensure defined startup behavior.

Key Specifications

Pinout & Package

TCR3UM28A,LF is housed in the ultra-small DFN4/DFN4E package (1.0 mm × 1.0 mm, max height 0.60 mm), weighing 1.3 mg. The exposed center pad must be connected to GND for optimal thermal performance and EMI suppression.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-quiescent-current LDO applications.

Compared with XC6210B282MR-G and BD3572EFJ-ME2, the TCR3UM28A,LF delivers superior quiescent current efficiency, tighter output accuracy, and integrated auto-discharge - making it optimal for battery longevity and rapid system shutdown in miniaturized portable electronics.

Availability

TCR3UM28A,LF is available at Aetrix Electronics and suitable for wearable sensors, Bluetooth LE modules, and industrial IoT edge nodes requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for TCR3UM28A,LF 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

Toshiba Electronic Devices & Storage Corporation designs high-efficiency, miniature semiconductor solutions for consumer, industrial, and automotive markets, with emphasis on power management and analog integration.

The TCR3UM series was developed specifically for ultra-low-power portable electronics, targeting applications where board area, battery life, and transient performance are critical constraints - exemplified by the TCR3UM28A,LF's 1.0 mm × 1.0 mm footprint and sub-1 μA quiescent current.

FAQ

What is the guaranteed output voltage accuracy of TCR3UM28A,LF over temperature?

The TCR3UM28A,LF guarantees ±1.0% output voltage accuracy across the full operating temperature range of −40°C to +85°C for its 2.8 V output. This specification is explicitly confirmed in the Electrical Characteristics table (Section 9) under "Output voltage accuracy" for VOUT ≥ 1.8 V, and applies directly to the TCR3UM28A,LF variant.

Does TCR3UM28A,LF require external capacitors, and what values are recommended?

Yes, the TCR3UM28A,LF requires both input (CIN) and output (COUT) capacitors. The datasheet specifies minimum values of ≥1.0 μF each, and confirms stable operation with ceramic capacitors having ESR <10 Ω. Using 1 μF X5R/X7R ceramics placed adjacent to the TCR3UM28A,LF pins satisfies all stability and transient requirements without additional components.

How does the CONTROL pin function on TCR3UM28A,LF, and what are its voltage thresholds?

The CONTROL pin on TCR3UM28A,LF enables or disables regulation. It turns ON when voltage is ≥1.0 V and OFF when ≤0.4 V. An internal 0.1 μA pull-down ensures the TCR3UM28A,LF defaults to OFF if the pin is unconnected. When disabled, the auto-discharge function actively pulls VOUT to GND through a 7 Ω internal path.

What thermal protection features are built into TCR3UM28A,LF?

The TCR3UM28A,LF incorporates thermal shutdown that activates at 158°C junction temperature, with 28°C hysteresis to prevent oscillation near the trip point. This protection is independent of load and input conditions, and is warranted by design per Section 9 of the datasheet. It safeguards the TCR3UM28A,LF during sustained overload or inadequate PCB heat sinking.

Can TCR3UM28A,LF operate from a 2.5 V input while delivering 2.8 V output?

No. The TCR3UM28A,LF cannot regulate 2.8 V output from a 2.5 V input because the minimum input voltage must exceed the output voltage by the dropout voltage. At 300 mA load, dropout is 196 mV (typ.), so VIN must be ≥2.996 V. The absolute minimum VIN specified is 1.5 V, but functional regulation at 2.8 V requires VIN ≥ VOUT + VDO - confirmed in Section 6 (Operating Ranges) and Figure 13.4 (Dropout vs. IOUT).