Renesas ISL97519IUZ-T

Overview

ISL97519IUZ-T from Intersil is a high-efficiency, constant-frequency PWM step-up regulator with integrated 2.0A/200mΩ MOSFET, 1% output voltage accuracy, selectable 600kHz/1.2MHz switching frequency, and operation from 2.3V to 5.5V input to deliver up to 1A at 12V output - optimized for TFT-LCD bias supplies in portable displays.

For engineers reviewing the ISL97519IUZ-T datasheet, ISL97519IUZ-T pinout, ISL97519IUZ-T application, or ISL97519IUZ-T equivalent, key selection criteria include its 1.294V feedback reference, external compensation flexibility, soft-start control via SS pin, thermal shutdown at 150°C, and 8-lead MSOP package with 1.1mm max height.

Technical Context

The ISL97519IUZ-T uses current-mode PWM control with an internal transconductance error amplifier (70–150 µS) and selectable oscillator frequency (620kHz or 1.25MHz). Its duty cycle is limited to 85–92% depending on FSEL state, enabling stable boost operation across 1.1×VIN to 25V output range.

It features dedicated pins for loop compensation (COMP), feedback (FB), soft-start timing (SS), and frequency selection (FSEL), supporting design of compact, low-ESR ceramic capacitor-based power stages with fast transient response and tight load regulation (≤0.3%) over -40°C to +105°C ambient.

Key Specifications

Pinout & Package

The ISL97519IUZ-T is housed in an 8-lead MSOP package (JEDEC MO-187-AA compliant, M8.118A drawing) with 0.65mm pitch, 3.0mm × 4.9mm body, and 1.1mm maximum profile - suitable for automated SMT assembly and thermally constrained applications.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ISL97519IUZ-T, the ISL97519A offers direct replacement with tighter thermal specs and updated UVLO, while TPS61088RHLR provides higher current capability and programmability at the cost of redesign effort and non-pin-compatibility.

Availability

ISL97519IUZ-T is available at Aetrix Electronics and suitable for TFT-LCD displays, DSL modems, and portable equipment requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for ISL97519IUZ-T 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 converters, precision references, and interface solutions.

The ISL97519 product line was developed specifically for compact, high-efficiency boost applications in portable displays and communication devices - emphasizing low quiescent current, small solution size, and robust thermal behavior.

FAQ

What is the guaranteed minimum peak switch current for ISL97519IUZ-T?

The ISL97519IUZ-T guarantees a minimum peak switch current of 1.7A across temperature and process variation, with a typical rating of 2.0A and on-resistance of 200mΩ. This limit directly constrains maximum output current based on input/output voltage ratio and inductor selection, as defined in Equation 7 of the FN6454 datasheet. Designers must verify peak inductor current remains below this threshold under worst-case conditions to avoid current-limit foldback or thermal shutdown.

Can ISL97519IUZ-T operate with a 2.3V input supply?

Yes, ISL97519IUZ-T operates down to 2.3V input voltage, with VDD UVLO turn-on threshold specified at 2.1–2.3V and 100mV hysteresis. At 2.3V input, it can still deliver regulated output (e.g., 12V) at reduced load - verified in typical performance curves (Figure 1 and Figure 2) showing >80% efficiency at VIN = 2.3V, VOUT = 9V, and IOUT = 200mA. This makes ISL97519IUZ-T suitable for single-cell Li-ion applications nearing end-of-discharge.

How does the FSEL pin affect switching frequency accuracy in ISL97519IUZ-T?

The FSEL pin selects between two nominal switching frequencies: grounded for 620kHz (±17% tolerance, 500–740kHz) or tied to VDD for 1.25MHz (±20%, 1.0–1.5MHz). This selection alters the oscillator's internal current source and capacitor charging rate. The frequency accuracy is specified over full temperature and supply range, and impacts inductor sizing, output ripple, and EMI filter design - 1.25MHz enables ~50% smaller inductors than 620kHz for equivalent ripple and transient response.

What is the role of the COMP pin in ISL97519IUZ-T loop compensation?

The COMP pin is the output of the internal transconductance error amplifier (70–150 µS) and serves as the connection point for the external RC compensation network (resistor to ground and capacitor to ground). This network sets the dominant pole and zero of the voltage loop to stabilize the current-mode control architecture. Proper COMP network design - typically 2k–7.5kΩ and 3–10nF - ensures phase margin >45° and adequate gain margin, especially critical when using low-ESR ceramic output capacitors that reduce natural damping.

Does ISL97519IUZ-T support output voltages above 25V?

No, ISL97519IUZ-T has an absolute maximum LX-to-GND rating of 27V and is specified for output voltages up to 25V. For outputs exceeding 25V, the datasheet recommends a cascaded MOSFET topology (Figure 13) where an external N-channel MOSFET replaces the internal switch, with gate driven by LX and source connected to VIN. In such configurations, the ISL97519IUZ-T acts as a controller only - the internal 25V-rated MOSFET is bypassed, and external device voltage rating must exceed the target output voltage.