Abstract: A method includes obtaining test criteria for a monitor configured to be attached to a user; obtaining reference data; determining, based on the test criteria and the reference data, a detached state of the monitor. The determining the detached state includes performing a set of tests indicated in the test criteria. The set of tests includes a first test corresponding to a first power consumption by the monitor; and a second test different from the first test. The second test corresponds to a second power consumption by the monitor, and the second power consumption is larger than the first power consumption. The method further includes automatically modifying, in response to the determining the detached state, an operating mode of the monitor.

Abstract: A battery charging aparatus and method are provided for charging a battery using current control with a switching power supply charging circuit coupled to the battery. During a first charging phase, a predetermined constant charging current is applied to the battery. The battery voltage is monitored and a second charging phase is started when the battery voltage reaches a predetermined threshold voltage. During a second charging phase, a sequence of stepwise decreasing-amplitude current pulses are applied to the battery. The envelope for the decreasing current pulses is exponential which is characteristic of the current for voltage controlled charging methods. The battery voltage is maintained at a temperature compensated target with a 1% tolerance. The charging current is compared to a predetermined minimum amplitude value and a third charging phase is started when the sequential charging current pulse equals the predetermined minimum amplitude value.