Keithley 2304A

The Model 2303/2304A Power Supplies provide both voltage control and power consumption monitoring for automated testing of portable, battery-operated devices. These power supplies are optimized for testing battery-operated, wireless communication devices such as cellular phones that undergo substantial load changes for very short time intervals. These power supplies exhibit outstanding voltage stability during pulse load changes and can simultaneously measure load currents, even if they are short pulses. In addition, this family of power supplies can sink current and, thus, take on the characteristics of a discharged, rechargeable battery for testing chargers and charger-control circuitry.

Both the 100W Model 2304A and the 45W Model 2303 can supply 5A (at 20V for the Model 2304A and 9V for the Model 2303) to serve the peak pulse loading requirements of battery-operated devices. In both instruments, the maximum current of 5A can be delivered continuously. The Model 2304A can supply up to 20V DC while the Model 2303 can supply up to 15V.

Keithley's High Speed Power Supplies are designed to simu late the current drive capacity of a battery. The power supplies simulate a battery's re sponse during a large load change by minimizing the maximum drop in voltage and recovering to within 100mV of the original voltage in 40us or less.

When a portable device such as a cellular phone switches from standby mode to the full power mode of operation, the current draw on the power supply can change by as much as 1000%. While a battery's voltage will de crease by the value of the voltage drop across the battery's low internal resistance, a conventional power supply will have a significant voltage drop (more than one volt) and take milli seconds to recover to the original voltage level. For portable devices that operate at full power only for short intervals, the full power event is over before a conventional power supply can recover. For example, cellular phones designed in accordance with the GSM cellular phone standard transmit and receive information in 576 ìs pulses. If the power supply used to test them cannot recover quickly enough, the performance of the device under-test will be compromised by the power supply. If the power supply voltage drops below the threshold of the phone's low- battery detection circuitry for a sufficient amount of time, the phone will turn off during testing, giving a false indication of a failed device.

The Models 2303/2304A's fast transient response to large load changes will enable test engineers to test their portable products properly and eliminate false failures due to conventional power supplies with slow response times. In this way, the power supplies ensure maximum production throughput when testing portable devices.