Renesas EL7554IRE

Overview

EL7554IRE from Intersil is a monolithic synchronous 4A step-down DC/DC regulator with integrated CMOS power FETs, operating from 3V to 6V input and delivering adjustable output down to 0.8V. It achieves up to 96% efficiency at 4A continuous load, supports 1MHz switching frequency, and includes junction temperature monitoring and ±5% voltage margining for manufacturing test validation. It is used in FPGA core/I/O power supplies requiring compact, thermally robust point-of-load regulation.

For engineers reviewing the EL7554IRE datasheet, EL7554IRE pinout, EL7554IRE application, or EL7554IRE equivalent, this page delivers verified technical context, package-validated pin functions, real-world start-up control configurations, thermal design guidance for HTSSOP-28, and confirmed alternative regulators for PoL supply redesigns.

Technical Context

The EL7554IRE implements constant-frequency PWM control with patented resistorless current sensing for fast transient response and over-current protection. Its dual CMOS power stage (PMOS high-side + NMOS low-side) enables true 100% duty cycle operation and eliminates boot capacitor requirements.

It integrates full start-up sequencing via STP/STN tracking inputs, soft-start with programmable delay, power-good indication with ±10% window, and on-die thermal shutdown at 135°C with 20°C hysteresis. The VTJ pin provides linear voltage output (1.2V @ 75°C) calibrated to junction temperature per TJ = (VTJ − 1.2)/0.00384 + 75.

Key Specifications

Pinout & Package

The EL7554IRE is housed in a thermally efficient 28-lead HTSSOP package (MDP0048) with an exposed thermal pad requiring solder connection to PCB ground plane for optimal heat dissipation. Layout guidelines mandate ≥13–25 mil thermal vias under the pad, no thermal reliefs, and separation of PGND (power ground) and SGND (signal ground) with single-point connection at SGND pin.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS544B20RTWR and MP2315GJ-Z, the EL7554IRE uniquely combines 3–6V input compatibility, junction temperature monitoring, ±5% voltage margining, and HTSSOP-28 thermal performance-making it the only option validated for FPGA core rail validation and thermally constrained portable designs.

Availability

EL7554IRE is available at Aetrix Electronics and suitable for FPGA core power supplies, DSP/CPU I/O regulation, logic/bus voltage conversion, and portable equipment power management requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for EL7554IRE 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

Intersil Corporation (now part of Renesas Electronics) is a U.S.-based analog and power management IC designer known for high-performance DC/DC regulators, precision amplifiers, and interface solutions.

The EL7554IRE belongs to Intersil's monolithic synchronous buck regulator product line, engineered specifically for high-density point-of-load applications in FPGA, DSP, and CPU subsystems where thermal efficiency, sequencing control, and manufacturing testability are critical.

FAQ

What is the maximum continuous output current supported by the EL7554IRE?

The EL7554IRE supports 4A continuous output current under specified thermal conditions (TA = −40°C to +85°C, proper PCB layout with thermal vias). Peak current limit is 6A, but sustained operation above 4A requires derating based on ambient temperature and copper area - see Figure 10 in the FN7360 datasheet for allowable power dissipation curves. The EL7554IRE's 28-lead HTSSOP package with exposed thermal pad enables this rating without external heatsinking.

Does the EL7554IRE require an external boot capacitor?

No, the EL7554IRE does not require an external boot capacitor because it uses a PMOS high-side switch instead of an NMOS. This architecture eliminates the need for charge-pump or bootstrap circuitry, simplifying layout and reducing component count. The EL7554IRE's integrated CMOS power stage (PMOS + NMOS) enables true 100% duty cycle operation and inherent bootstrap-free operation - a key differentiator from many competing buck controllers.

How is the junction temperature monitored on the EL7554IRE?

The EL7554IRE provides junction temperature monitoring via the VTJ pin, which outputs a linear analog voltage: VTJ = 1.2V − 0.00384 × (TJ − 75). Measuring VTJ with a precision ADC allows direct calculation of die temperature TJ. This feature replaces external thermal sensors and accelerates thermal characterization - especially valuable during FPGA/DSP system validation. The EL7554IRE's VTJ pin is internally calibrated and requires only a 0.01–0.047µF capacitor to SGND for noise filtering.

Can the EL7554IRE synchronize its switching frequency to an external clock?

Yes, the EL7554IRE supports external synchronization via the COSC pin. An AC-coupled external clock signal (with amplitude >1.2Vpp and frequency 20% higher than the internal oscillator setting) can be injected through a series capacitor. To avoid beat frequencies, the internal switching frequency should be set ~20% lower than the sync source - e.g., configure COSC for 800kHz when syncing to a 1MHz master clock. This capability is documented in Figure 20 of the EL7554IRE datasheet FN7360.

What are the recommended layout practices for the EL7554IRE's thermal pad?

The EL7554IRE's exposed thermal pad must be soldered to a solid PCB ground plane using ≥6 thermal vias (13–25 mil diameter) placed directly beneath the pad, with no thermal reliefs. Copper area should extend beyond the package outline, and PGND traces must be wide and short. Per Figure 25 in FN7360, this layout achieves θJA ≈ 26°C/W on a 2-layer board. Failure to follow these guidelines risks thermal shutdown under 4A load - the EL7554IRE's performance is layout-dependent, not just datasheet-guaranteed.