ISL9204 is a high input voltage single-cell Li-ion battery charger from Intersil. This charger can accept up to 28V input voltage, but is disabled when the input voltage exceeds the OVP threshold (minimum 10V) to prevent excessive power dissipation. The 28V rating eliminates the overvoltage protection circuit required in a low input voltage charger. The charge current and the end-of-charge (EOC) current are programmable with external resistors. When the battery voltage is lower than a typical value of 2.8V, the charger preconditions the battery with typically 17% of the programmed charge current. When the charge current reduces to the programmable EOC current level during the CV charge phase, an EOC indication is provided by the CHG pin, which is an open-drain output. An internal thermal foldback function protects the charger from any thermal failure. Two indication pins (PPR and CHG) allow simple interface to a microprocessor or LEDs. When no adapter is attached or when disabled, the charger will enter a low power mode until a battery is connected or the charger is enabled.
The ISL9204 provides a cost‑effective, fully integrated solution for charging single‑cell Li‑ion or Li‑polymer batteries. It performs constant‑current/constant‑voltage (CC/CV) charging, accepts an input voltage up to 28 V, and disables charging when the input exceeds the over‑voltage‑protection threshold.
Key features include programmable charge and end‑of‑charge currents, thermal foldback protection, low leakage current (<1 A when disabled), and two indication pins (PPR and CHG) for easy interfacing with LEDs or a microcontroller. Typical applications are mobile phones, Bluetooth devices, PDAs, MP3 players, stand‑alone chargers, and other handheld devices.
| Maximum Input Voltage | 28 V |
|---|---|
| Programmable Charge Current | 50 mA to 350 mA |
| Programmable End‑of‑Charge Current | 5 % of IREF or ≥10 mA |
| Voltage Accuracy | ±1 % |
| Ambient Temperature Range | -40 °C to 85 °C |
| Leakage Current (no input) | < 1 A |
The charger can tolerate up to 28 V on its VIN pin before it disables charging.
When the end‑of‑charge current is reached, the CHG pin goes high‑impedance, providing an open‑drain indication of charge completion.
Yes, the charge current is set with an external resistor on the IREF pin, ranging from 50 mA to 350 mA.
Thermal foldback reduces the charge current when the internal temperature reaches about 115 °C.