MC33340 and MC33342 are monolithic control ICs specifically designed for fast charge control of Nickel Cadmium (NiCd) and Nickel Metal Hydride (NiMH) batteries. These devices use negative slope voltage detection as the primary method for fast charge termination. Accurate detection is ensured by momentarily interrupting the charge current for precise voltage sampling. An additional secondary termination method can be selected, either programmable time or temperature limit. Protective features include battery over and undervoltage detection, latched over temperature detection, and power supply input undervoltage lockout with hysteresis. The only difference between MC33340 and MC33342 is the fast charge holdoff time, with MC33340 having a typical holdoff time of 177 seconds and MC33342 having a typical holdoff time of 708 seconds.