Renesas ISL6297CR

Overview

ISL6297CR from Intersil is a dual-mode linear lithium-ion battery charger IC optimized for space-constrained travel chargers, featuring 4.2V ±0.7% constant-voltage regulation, programmable 1.0A charge current (via 80kΩ IREF resistor), THERMAGUARD™ thermal foldback at +100°C, and bi-color LED status indication for cellular phone charging applications.

For engineers reviewing the ISL6297CR datasheet, ISL6297CR pinout, ISL6297CR application, or ISL6297CR equivalent, this page delivers verified functional identity, validated QFN-16 package mapping, confirmed thermal foldback behavior, precise trickle/fast/EOC state transitions, and real-world design implications of its dual-mode operation with current-limited AC/DC adapters.

Technical Context

The ISL6297CR implements Intersil's patent-pending dual-mode architecture: it operates as a voltage-regulated linear charger when powered by a constant-voltage source, but switches to current-limited mode-where charge current is dictated by the adapter's ILIM-when supplied by a current-limited AC/DC converter, reducing thermal dissipation by up to 90% versus conventional linear chargers.

Its integrated P-channel MOSFET (rDS(ON) ≈ 400mΩ max), remote-sense VSEN feedback, NTC thermistor interface (TEMP pin), and two-level ambient temperature monitoring (charge/non-charge thresholds) enable autonomous, fault-aware charging in compact enclosures without external blocking diodes or discrete current sensing.

Key Specifications

Pinout & Package

ISL6297CR is housed in a thermally enhanced 4×4 mm, 16-lead QFN package (JEDEC MO-220 compliant) with exposed thermal pad (EPAD) internally connected to GND. The package enables high-density PCB layouts and improved thermal performance in space-limited travel charger designs.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar lithium-ion linear charger applications.

Compared with BQ24075RGER and MP2617GQZ, the ISL6297CR uniquely combines dual-mode thermal optimization, integrated plug-in verification, and two-level ambient temperature thresholds-making it irreplaceable for ultra-compact travel charger implementations where PCB area and thermal envelope are strictly bounded.

Availability

ISL6297CR is available at Aetrix Electronics and suitable for smartphone travel chargers, medical handheld battery packs, and standalone PDA chargers requiring stable component supply and long-term lifecycle continuity.

Supply support for ISL6297CR 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 (now part of Renesas Electronics) is a U.S.-based analog and power management IC designer known for high-efficiency battery management, precision voltage references, and thermally robust power solutions.

The ISL6297CR belongs to Intersil's Li-ion linear charger product line, engineered specifically for minimal thermal footprint in portable consumer electronics where physical integration into cables or connectors is mandatory.

FAQ

What is the primary function of the ISL6297CR in a travel charger design?

The ISL6297CR serves as a fully integrated dual-mode lithium-ion battery charger IC that eliminates external MOSFETs, blocking diodes, and current-sense resistors. In travel charger applications, its core function is to deliver precise 4.2V ±0.7% constant-voltage charging with programmable 1.0A current while minimizing thermal generation-enabling direct placement inside the USB connector housing. This architecture removes cable-induced voltage drop effects and ensures consistent charge performance across varying adapter qualities. The ISL6297CR achieves this through patented dual-mode operation and THERMAGUARD™ thermal foldback.

How does the ISL6297CR implement dual-mode charging, and why is it critical for travel chargers?

The ISL6297CR dynamically adapts to its power source: with constant-voltage adapters, it behaves like a standard linear charger; with current-limited AC/DC converters, it leverages the adapter's ILIM to set charge current-reducing power dissipation by shifting from (VIN−VBAT)×I to rDS(ON)×I². This dual-mode operation is critical for travel chargers because it allows the ISL6297CR to be embedded directly in the connector, where airflow and heatsinking are nonexistent. Without this feature, thermal buildup would exceed +150°C under worst-case conditions. The ISL6297CR's ability to operate reliably at +100°C junction temperature-then fold back current-makes it uniquely viable for this mechanically constrained application.

What role does the VSEN pin play in the ISL6297CR, and how should it be routed on the PCB?

The VSEN pin on the ISL6297CR provides remote voltage sensing feedback to compensate for voltage drops across PCB traces, connectors, and contacts between the IC and battery anode. It must be routed as a dedicated, low-impedance trace directly to the battery's positive terminal-separate from the main BAT power path-to ensure accurate 4.2V regulation despite parasitic resistance. Incorrect routing (e.g., tying VSEN to BAT locally) causes overvoltage stress on the cell, risking safety violations. The ISL6297CR's 0.7% voltage accuracy specification assumes proper VSEN placement; deviation introduces up to ±30mV error per 100mΩ of un-compensated resistance. Always place VSEN decoupling capacitor ≤2mm from the battery terminal.

Can the ISL6297CR be used without an NTC thermistor, and what happens to temperature protection?

Yes, the ISL6297CR can operate without an NTC thermistor connected to the TEMP pin, but ambient temperature monitoring is then disabled-removing the –5°C to +45°C non-charge and 0°C to +45°C charge window enforcement. However, THERMAGUARD™ thermal foldback remains fully functional: the IC still monitors its own junction temperature and reduces charge current above +100°C. This means battery-level cold/hot charging prevention is lost, but die-level thermal safety is preserved. For applications where ambient extremes are unlikely (e.g., indoor consumer devices), omitting the NTC simplifies BOM and layout. For medical or outdoor equipment, the NTC is mandatory-and the ISL6297CR's two-level threshold configuration must be implemented using external resistor dividers on the TEMP pin.

What is the purpose of the plug-in LED sequence (red → green → yellow → off) on the ISL6297CR?

The plug-in LED sequence on the ISL6297CR is a hardware-based power-on self-test that verifies adapter presence, IC functionality, and basic LED driver integrity before any battery interaction occurs. It activates automatically when VIN exceeds the 3.4V POR threshold: red LED (500ms), green LED (500ms), both LEDs (500ms = yellow), then all off. This sequence confirms the V2P9 2.9V rail is stable, oscillators are running, and GRN/RED drivers can sink 10mA-eliminating the need for firmware-based diagnostics. If the sequence fails (e.g., no yellow flash), the issue lies in input supply quality, decoupling, or LED wiring-not battery connection. This diagnostic is unique to the ISL6297CR and is critical for field-repairable travel charger designs where serviceability must be hardware-verified.