CAMARILLO, Calif. - Semtech Corp. 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. SC805 and SC806 chargers feature an input voltage range of 3V to 6V for seamless
charging from a current-limited adapter. This feature assures that for high output current designs, the power
dissipation can occur in a less-sensitive wall plug adapter rather than in the system’s internal charging
circuitry itself. The SC805 and SC806 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, the SC805 offers 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
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.” 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 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. The lead-free package design complies with the European
Union’s Restriction on Hazardous Substances in Electrical and Electronic Equipment (RoHS) directive to meet
worldwide environmental and regulatory requirements. Key Features of the SC805 / SC806
· Highly accurate charge
current · Tiny 3mm x 3mm 10-lead MLP
package · Battery voltage controlled to 1%
accuracy over the full Industrial temperature range · SC805: NTC thermistor safely disables the charge
cycle when temperature is out of range · SC805:
Contains an auxiliary output pin for external accessories or bootstrap for USB charging · 0.1µA 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 |