Renesas EL7564CREZ

Overview

EL7564CREZ from Intersil is a monolithic synchronous step-down DC/DC regulator delivering 4A continuous output current with adjustable output voltage from 1.0V to 3.8V, operating at up to 95% efficiency and constant-frequency PWM mode across -40°C to +85°C ambient. It integrates high- and low-side NMOS FETs (30–60 mΩ R_DS(on)), on-chip resistorless current sensing, junction temperature monitoring (VTJ), and power-good indication (PG) for DSP/CPU core supply applications.

For engineers reviewing the EL7564CREZ datasheet, EL7564CREZ pinout, EL7564CREZ application, or EL7564CREZ equivalent, key selection considerations include its 28-pin HTSSOP package with exposed thermal pad, 4.5V–5.5V input range, ±0.5% line/load regulation, 135°C overtemperature shutdown, and support for external oscillator synchronization and auxiliary supply tracking (STP/STN).

Technical Context

The EL7564CREZ implements current-mode PWM control using patented on-chip resistorless current sensing, enabling cycle-by-cycle current limiting and fast load transient response. Its oscillator supports adjustable frequency up to 1 MHz via COSC capacitor and external synchronization with ≥20% frequency margin.

Power tracking is implemented via STP/STN comparator inputs to coordinate startup sequencing of multiple supplies, while the VTJ pin provides linear voltage output (1.2V at 25°C, slope −3.84 mV/°C) directly proportional to junction temperature for real-time thermal monitoring without external sensors.

Key Specifications

Pinout & Package

EL7564CREZ is housed in a 28-pin HTSSOP package with exposed thermal pad (MDP0048), requiring soldering of the pad to PCB copper for optimal thermal performance (θ_JA ≈ 29°C/W). Pin functions are validated per FN7297 Rev 3.00 datasheet.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ISL8024 and TPS544B20, EL7564CREZ offers unique analog power tracking and junction temperature monitoring in a mature, cost-optimized 28-pin HTSSOP package - ideal for fixed-function, thermally constrained applications where digital overhead is unnecessary.

Availability

EL7564CREZ is available at Aetrix Electronics and suitable for DSP core supplies, portable equipment power rails, and DC/DC converter modules requiring stable component supply, RoHS compliance, and long-term industrial availability.

Supply support for EL7564CREZ 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) designs high-performance analog and power management ICs for industrial, computing, and communications markets.

The EL7564 product line delivers fully integrated synchronous buck regulators targeting high-current, low-voltage processor and logic supply applications with emphasis on thermal efficiency, sequencing control, and minimal external component count.

FAQ

What is the maximum recommended input voltage for EL7564CREZ?

The absolute maximum input voltage between VIN or VDD and GND is +6.5V, but the recommended operating input range is strictly 4.5V to 5.5V per the datasheet's DC electrical specifications. Operating outside this range may degrade regulation accuracy, efficiency, or reliability. EL7564CREZ is optimized for standard 5V system rails, and sustained operation above 5.5V risks exceeding internal FET voltage ratings and thermal limits.

Does EL7564CREZ require an external current sense resistor?

No, EL7564CREZ uses patented on-chip resistorless current sensing to monitor inductor current through the high-side NMOS FET during conduction. This eliminates the need for an external sense resistor, reducing power loss, board space, and component count. The sensed current enables cycle-by-cycle limiting, overcurrent protection, and stable current-mode control without external hardware - a key differentiator of the EL7564CREZ design.

How is the output voltage set on EL7564CREZ?

The output voltage is set externally via a resistor divider from VOUT to SGND, connected to the FB pin. For the EL7564CREZ variant, the internal feedback reference is 0.992V (typical), so VOUT = 0.992V × (1 + R2/R1). A 125nA internal pull-up current forces VOUT to SGND if FB is left floating, providing fail-safe behavior. Resistor values must be selected to ensure FB bias current error remains below ±0.5% of target output.

What thermal management is required for EL7564CREZ in a 28-pin HTSSOP package?

The EL7564CREZ HTSSOP package relies on soldering its exposed thermal pad to a large PCB copper area for effective heat dissipation. With proper pad connection, θ_JA can reach 29°C/W (no airflow). Layout must minimize thermal resistance by using multiple vias under the pad to inner-layer ground planes. The VTJ pin provides direct die temperature monitoring - at 135°C junction, thermal shutdown activates, and hysteresis resets at 115°C.

Can EL7564CREZ synchronize its switching frequency to an external clock?

Yes, EL7564CREZ supports external oscillator synchronization via its SYNC-capable architecture. To implement this, the free-running frequency (set by COSC) must be at least 20% lower than the external sync source frequency to accommodate component and temperature variations. Figure 23 in FN7297 shows a typical implementation using a BAT54S diode and 100pF capacitor to inject the sync signal into the COSC node - ensuring jitter-free, phase-locked operation across multiple converters.