Diodes Incorporated AP2115R5-1.8TRG1

Overview

AP2115R5-1.8TRG1 from BCD Semiconductor is a 1.8V fixed-output, 1A CMOS low-dropout linear regulator in SOT-89-5 package with enable control, ±1.5% output accuracy, 450mV typical dropout at 1A, and 30µV_RMS output noise. It delivers stable power to noise-sensitive analog circuits in LCD monitors and STB applications.

For engineers reviewing the AP2115R5-1.8TRG1 datasheet, AP2115R5-1.8TRG1 pinout, AP2115R5-1.8TRG1 application, or AP2115R5-1.8TRG1 equivalent, key selection criteria include dropout voltage under full load, PSRR at 1kHz, thermal shutdown threshold, EN logic thresholds, and compatibility with 4.7µF ceramic output capacitors.

Technical Context

The AP2115R5-1.8TRG1 integrates a CMOS pass transistor with internal bandgap reference, error amplifier, and thermal shutdown circuitry. Its enable input supports active-high logic control (VIH ≥1.5V), and it features fold-back short-circuit protection limiting output current to 50mA during fault conditions.

It operates across -40°C to +85°C ambient temperature with input voltage range 2.8V–6.0V and maintains ±1.5% output accuracy over line, load, and temperature. The device achieves 68dB PSRR at 1kHz and stabilizes with 4.7µF ceramic, tantalum, or aluminum electrolytic capacitors.

Key Specifications

Pinout & Package

SOT-89-5 package: compact 5-pin surface-mount outline with exposed thermal pad (θ_JC = 47°C/W), optimized for thermal dissipation in space-constrained consumer PCBs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1703T-1802E/MB and XC6210B182MR-G, the AP2115R5-1.8TRG1 uniquely combines 1A output, integrated enable, 450mV dropout, and 30µV_RMS noise - making it the only option among the three qualified for noise-critical, high-current display power rails.

Availability

AP2115R5-1.8TRG1 is available at Aetrix Electronics and suitable for LCD monitor power, set-top box core supply, and industrial display module applications requiring stable component supply, RoHS-compliant packaging, and tape-and-reel delivery for automated assembly.

Supply support for AP2115R5-1.8TRG1 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

BCD Semiconductor Manufacturing Limited is a Shanghai-based analog and power IC designer specializing in high-performance, cost-optimized semiconductor solutions for consumer, industrial, and computing markets.

The AP2115 product line targets low-noise, high-current LDO applications in display electronics and digital consumer equipment, emphasizing capacitor flexibility, thermal robustness, and tight DC accuracy.

FAQ

What is the minimum input voltage required for AP2115R5-1.8TRG1 to regulate 1.8V at 1A?

The datasheet specifies a minimum input voltage of 2.8V for 1.8V output operation. At 1A load, the 450mV typical dropout requires VIN ≥ 2.25V theoretically, but the recommended operating condition mandates VIN ≥ 2.8V to guarantee regulation across temperature, line, and load variations - ensuring 1.8V ±1.5% output stability under worst-case conditions.

Can AP2115R5-1.8TRG1 be used with a 2.2µF ceramic output capacitor?

No - the datasheet explicitly requires ≥4.7µF for stability across ceramic, tantalum, and aluminum electrolytic types. Using 2.2µF risks oscillation or poor transient response, as verified in Figure 14–17 showing output voltage deviation under load steps with 4.7µF COUT. Layout parasitics further reduce effective capacitance, making undersized caps noncompliant.

Does AP2115R5-1.8TRG1 support reverse polarity protection on the input?

No - the device lacks internal reverse-voltage protection. Applying negative voltage to VIN relative to GND exceeds the Absolute Maximum Rating of -0.3V and may cause latch-up or permanent damage. External protection (e.g., series Schottky diode) is required in systems prone to input reversal.

How does the EN pin behave when left unconnected?

The EN pin has an internal 3.0MΩ pull-down resistor, so an unconnected EN defaults to logic low, disabling the regulator output. To enable operation, EN must be actively driven ≥1.5V (e.g., tied to VIN or a GPIO). This default-off behavior prevents unintended power-up during board insertion or hot-swap events.