Renesas ISL9238HRTZ

Overview

ISL9238HRTZ from Renesas Electronics is a buck-boost Narrow VDC (NVDC) battery charger IC for 1–4-cell Li-ion systems, supporting input voltage range 3.2V–23.4V, system output regulation from 2.4V–18.304V, and up to 1MHz switching frequency. It delivers autonomous charging, PSYS power monitoring for IMVP8 platforms, and reverse buck/boost/buck-boost operation from battery.

For engineers reviewing the ISL9238HRTZ datasheet, ISL9238HRTZ pinout, ISL9238HRTZ application, or ISL9238HRTZ equivalent, key selection considerations include NVDC topology compatibility with USB-C PD sources, IMVP8-compliant PSYS/PROCHOT# signaling, adapter+battery dual-power arbitration, and SMBus-programmable charge parameters in space-constrained portable designs.

Technical Context

The ISL9238HRTZ implements Renesas R3™ Technology for high light-load efficiency and fast transient response in dynamic load scenarios typical of Ultrabook and tablet platforms. Its dual-phase synchronous buck-boost architecture enables seamless transition between adapter-only, battery-only, and hybrid power modes without system voltage droop.

It integrates dedicated analog monitors-AMON for adapter current and BMON for battery current-and supports two-level adapter current limiting with programmable thresholds via SMBus. The PSYS output provides a continuous analog representation of total platform power, directly compatible with IMVP8 core regulators.

Key Specifications

Pinout & Package

ISL9238HRTZ is housed in a 4×4 mm, 32-lead TQFN package with exposed thermal pad (Renesas package code HRTZ). Pin functions are validated per FN8877 Rev.9.00.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar buck-boost NVDC charger applications.

Compared with BQ25703A and MP2731, the ISL9238HRTZ uniquely combines IMVP8-compliant PSYS/PROCHOT# signaling, R3™ fast transient response, and true dual-input/dual-output NVDC arbitration-making it the only option for Intel-based Ultrabooks and convertible notebooks requiring certified platform power management.

Availability

ISL9238HRTZ is available at Aetrix Electronics and suitable for Ultrabook power subsystems, USB-C PD power banks, and convertible notebook battery management systems requiring stable component supply, long-term lifecycle support, and IMVP8 platform certification readiness.

Supply support for ISL9238HRTZ 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

Renesas Electronics Corporation is a global semiconductor leader delivering microcontrollers, analog, power, and SoC solutions for automotive, industrial, infrastructure, and IoT applications.

The ISL9238HRTZ belongs to Renesas' high-efficiency battery charger product line, engineered specifically for USB-C and IMVP8-compliant portable computing platforms requiring robust dual-power-path arbitration and precise system bus regulation.

FAQ

What is the maximum supported battery cell count for the ISL9238HRTZ?

The ISL9238HRTZ supports 1-, 2-, 3-, or 4-cell Li-ion battery configurations. This is confirmed in the device's official datasheet FN8877 Rev.9.00, which specifies operation across the full range with automatic cell-count detection and corresponding charge voltage scaling. The ISL9238HRTZ applies appropriate termination voltages (e.g., 4.2V/cell for standard Li-ion) and adjusts current limits accordingly without external configuration.

Does the ISL9238HRTZ support USB On-The-Go (OTG) functionality?

Yes, the ISL9238HRTZ supports reverse buck, boost, and buck-boost operation from the battery to the input port, enabling USB OTG. It regulates output to standard USB-C PD voltages (5V/9V/15V/20V) using its internal control loop and SMBus-programmable settings. The ISL9238HRTZ achieves this without requiring additional DC-DC stages, as verified in Figure 1 and Section 7.2 of FN8877 Rev.9.00.

Is the ISL9238HRTZ pin-compatible with other members of the ISL923x family?

No, the ISL9238HRTZ is not pin-compatible with ISL9237 or ISL9239. While sharing the same 32-lead TQFN package outline, pin assignments differ significantly-for example, PSYS and PROCHOT# are unique to ISL9238HRTZ and absent on ISL9237. Layout reuse is not possible without redesign, as confirmed by comparing pinout tables in FN8877 Rev.9.00 and FN8876 Rev.7.00.

What is the purpose of the AMON and BMON pins on the ISL9238HRTZ?

The AMON and BMON pins on the ISL9238HRTZ provide analog voltage outputs proportional to adapter input current and battery current, respectively. Each delivers 100mV/A scaling with ±3% accuracy over temperature, enabling real-time power budgeting and hardware-based overcurrent protection. These signals are referenced in Table 2 and Section 8.3 of FN8877 Rev.9.00 and require no external amplification for MCU ADC interfacing.

Can the ISL9238HRTZ operate without an SMBus host controller?

Yes, the ISL9238HRTZ supports autonomous charging mode with default factory-programmed parameters, allowing full operation-including charge termination, safety timers, and VSYS regulation-without SMBus communication. However, features like PSYS calibration, PROCHOT# threshold adjustment, and OTG voltage selection require SMBus access. This dual-mode capability is explicitly documented in Section 3.2 of FN8877 Rev.9.00.