The Model 2308 Portable Device Battery/Charger Simulator is optimized for use in testing mobile phones and other portable, battery-operated devices. When a device-under-test (DUT) transitions nearly instantaneously from a sleep or standby mode to the full power transmit state, the rapid response to load changes means there's little transient voltage drop from the programmed output voltage and the output recovers quickly. This fast response is particularly critical when testing portable devices with a pulsed mode of operation because it allows the device to perform properly while it's being tested. In contrast, the slow-responding source voltage typical of conventional DC power supply products causes the DUT to perform improperly, leading to production yield problems and costly retesting.