Renesas EL7583IREZ

Overview

EL7583IREZ from Intersil is a 3-channel DC/DC converter IC designed for TFT-LCD panel power management, integrating a PWM boost regulator (5V–17V output, up to 470mA @12V), a positive charge pump (VON: +8V to +40V, 60mA), and a negative charge pump (VOFF: –5V to –40V, 60mA). It operates from 2.7V–14V input, features adjustable switching frequency (200–1000 kHz), soft-start control, and over-temperature shutdown at 130°C.

For engineers reviewing the EL7583IREZ datasheet, EL7583IREZ pinout, EL7583IREZ application, or EL7583IREZ equivalent, this device serves as a single-chip solution for column driver biasing, gate-on/gate-off voltage generation, and high-efficiency multi-rail TFT-LCD supply - with design-critical parameters including VBOOST load regulation (±0.5%), FOSC tuning via ROSC resistor, and independent ENP/ENBN sequencing control.

Technical Context

The EL7583IREZ implements a constant-frequency PWM boost converter with integrated N-channel MOSFET (RDS-ON = 0.22Ω), supporting 200–1000 kHz operation set by an external ROSC resistor. Its dual regulated charge pumps operate at half the boost frequency and use internal comparators with 1.310V reference to regulate VON and VOFF outputs independently.

Start-up employs a dedicated oscillator until VDDB reaches ~3.7V, then transitions to PWM regulation with current-limited soft-start controlled by SS pin capacitor charging. Over-temperature protection triggers at 130°C with 40°C hysteresis, disabling all channels without latch-up.

Key Specifications

Pinout & Package

EL7583IREZ is housed in a Pb-free 20-lead HTSSOP package (Moisture Sensitivity Level 3, RoHS-compliant), featuring an exposed thermal pad for enhanced power dissipation (θJA = 90°C/W on JEDEC JESD51-5 board).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar multi-output LCD bias applications.

Compared with MAX1674AEEE+ and TPS65105PWPR, EL7583IREZ uniquely delivers programmable triple-output power in one IC - enabling compact, thermally efficient TFT-LCD bias with sequenced startup, adjustable frequency, and full -40°C to +85°C operation - whereas alternatives require external components or sacrifice voltage range and control granularity.

Availability

EL7583IREZ is available at Aetrix Electronics and suitable for TFT-LCD panel manufacturing, industrial PDA production, and automotive display module development requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for EL7583IREZ 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 display, interface, and precision analog solutions.

The EL7583 product line was engineered specifically for TFT-LCD panel power systems, addressing the need for integrated, sequenced, and thermally robust multi-rail bias generation in space- and efficiency-constrained displays.

FAQ

What is the maximum output current capability of the EL7583IREZ boost converter at 15V?

The EL7583IREZ boost converter delivers up to 370mA at 15V output when supplied from a 5V input, as confirmed in the FN7335 datasheet (Page 1, "Features" section). This rating assumes standard operating conditions (TA = 25°C, ROSC = 100kΩ, continuous conduction mode) and accounts for internal FET RDS-ON (0.22Ω) and thermal limits. At higher ambient temperatures or with reduced input voltage, derating applies per the power dissipation curves on Page 8.

How does the EL7583IREZ implement independent sequencing of VON and VOFF startup?

The EL7583IREZ uses two dedicated enable inputs: ENBN controls both the boost converter and VOFF charge pump, while ENP independently enables the VON charge pump. By asserting ENBN first and delaying ENP via an RC network (e.g., 100kΩ + 0.1µF), designers achieve precise VBOOST → VOFF → VON sequencing - critical for avoiding latch-up in TFT gate driver ICs. This behavior is verified in Figure 15 (POWER-DOWN) and Figure 16 (POWER-UP) of the FN7335 datasheet.

Can the EL7583IREZ generate VON above +30V? What design considerations apply?

Yes - the EL7583IREZ supports VON up to +40V using external diode-capacitor charge pump stages, as detailed in Page 11's "Two-Stage Positive Charge Pump Circuit." To achieve >+30V, designers must select low-RON diodes (e.g., BAT54S), minimize parasitic capacitance, and ensure VDDP ≥ required VON/2. The datasheet specifies that VON max ≤ 2×VDDP − IOUT×(RONN+RONP) − 2×VDIODE, with RON ≈ 33Ω at 12V VDDP.

What is the function of the SS pin on the EL7583IREZ, and how is it configured?

The SS (Soft-Start) pin on the EL7583IREZ controls inrush current during power-up by limiting peak switch current via an external capacitor. A 12µA internal current source charges the SS capacitor, linearly increasing the current limit threshold and thus ramping VBOOST smoothly. For a 10ms soft-start time, a 120nF capacitor is recommended (12µA × 10ms = 120nF × 1V). This prevents input rail collapse and reduces stress on input capacitors and the internal FET.

Does the EL7583IREZ require external compensation components for stability?

No - the EL7583IREZ uses internal fixed-frequency PWM compensation optimized for standard 10µH inductors and ceramic output capacitors ≥10µF. However, a 1nF capacitor across the upper feedback resistor (R1) is recommended per Page 10 to suppress high-frequency noise coupling into the FBB node, especially at >700kHz switching frequencies. No external Type-II or Type-III compensation network is needed.