The LTC4123 is Linear Technology’s second wireless charger with a built-in receiver in the battery charging space, in addition to the LTC4120. The LTC4123 combines a wireless power receiver with a linear NiMH battery charger. Key features of the device include up to 25mA programmable charge current, temperature compensated charge voltage, Zinc-Air cell battery detection, reverse polarity detection, and compact packaging. The target applications include rechargeable NiMH battery powered hearing aids, small medical instruments, smart cards, wearables including fitness devices, IoT or Internet of Things systems, plus moving and/or rotating equipment-based systems.