The document introduces the MAX712/MAX713 fast-charge Nickel Metal Hydride (NiMH) and Nickel Cadmium (NiCd) batteries, from a DC source at least 1.5V higher than the maximum battery voltage.
The MAX712 and MAX713 are fast‑charge controllers for NiMH and NiCd batteries that can charge 1 to 16 series cells at rates up to 4 C. They use a voltage‑slope detector, temperature window comparator, and timer to determine charge completion, and can operate in linear or switch‑mode configurations.
The document provides detailed electrical characteristics, pin descriptions, ordering information, and typical application circuits. It also explains how to program the number of cells, set charge timeouts, and select external components such as a PNP transistor, diode, resistors, and capacitors.
They can charge from 1 up to 16 series cells.
Only an external power PNP transistor, a blocking diode, three resistors, and three capacitors are needed.
The MAX712 detects a zero voltage slope, while the MAX713 uses a negative voltage‑slope detection scheme to end fast charge.
The ADC input range is limited to between 1.4 V and 1.9 V.