IntroductionA leading supplier of analog and mixed-signal semiconductors for communications, portable devices, computers, and industrial equipment, today announced the SC805 and SC806 ultra-small battery charger devices designed for consumer electronics applications, including cable chargers, personal media devices, and mobile phones. Both devices charge lithium-ion or lithium-polymer batteries and are packaged in tiny 3mm x 3mm, thermally optimized MLP packages. The chargers produce up to 1A when operating in continuous charge mode, and during high power-dissipation periods they behave like pulse chargers that regulate the internal die temperature to a safe level.
Charge states They are designed with three programmable charge states, including a trickle-charge phase for deeply discharged batteries, a fast-charge phase, and a constant-voltage (CV) phase. In addition, they offer a programmable one- to 10-hour charge timer that protects a system from faulty batteries. All aspects can be programmed to facilitate a safe and accurate charging profile. The chargers feature an input voltage range of 3V to 6V.
Flexibility "The high-current level and charging profile flexibility of the SC805 and SC806 are critical key features, and the good news for designers is that all of this comes in a small, less expensive package," said C.S. Mitter, Semtech's Director of Power Management for Handheld Products. "Add to this an advanced thermal design, and it means these new chargers are well-positioned for the next generation of consumer devices."
Special features The SC805 and SC806 feature precise line and load regulation, enabling the devices to control battery voltage to 1% accuracy. Once the charger reaches CV mode, it gradually reduces battery output voltage until the termination voltage is reached and then monitors battery voltage levels and initiates a new charge cycle if the battery voltage drops by more than 100mV. The SC805 and SC806 are fully integrated devices, including charger, FET pass transistor, reverse-blocking diode, sense resistor, and thermal protection. In addition to charging lithium-ion or lithium-polymer batteries, the devices can work as general-purpose current sources or as current sources for charging Nickel-Cadmium (NiCd) and Nickel-Metal-Hydride (NiMH) batteries. The SC805 and SC806 can monitor a negative temperature coefficient pin to detect that the battery is not connected. The SC805 can work with or without a battery, functioning as a low dropout (LDO) regulator when the battery is removed. This LDO feature is helpful for "bed-of-nails" system testing where a portable device, such as a cell phone, is assembly tested without a battery.
Key features - Highly accurate charge current
- Tiny 3mm x 3mm, 10-lead MLP package
- Battery voltage controlled to 1% accuracy over the full temperature
- SC805: NTC thermistor disables the charge cycle when temperature is to high
- Contains an auxiliary output pin for external accessories or for USB charging
- 0.1 micron-A battery drain current in shutdown and monitor modes
- Over current protection in all charging modes
- Automatic loss of battery detection
- Adapter present, charge status, and no battery output LED drivers
Price and Availability The SC805, ordering code SC805IMLTRT, is available immediately in production quantities and is priced at $1.05 each in 10,000-piece lots. The SC806, ordering code SC806IMLTRT, is available immediately in production quantities and is priced at $1.01 each in 10,000-piece lots. Semtech offers comprehensive design assistance, including field- and factory-based support. Data sheets, volume pricing, and delivery quotes, as well as evaluation kits and samples, are available by contacting Semtech.
