JAJS013I December 2000 – September 2020 DCP010505B , DCP010505DB , DCP010507DB , DCP010512B , DCP010512DB , DCP010515B , DCP010515DB , DCP011512DB , DCP011515DB , DCP012405B , DCP012415DB
PRODUCTION DATA
When more than one DC/DC converter is needed onboard, beat frequencies and other electrical interference can be generated. This interference occurs because of the small variations in switching frequencies between the DC/DC converters.
The DCP01B series of devices overcomes this interference by allowing devices to synchronize to one another. Synchronize up to eight devices by connecting the SYNC pins of each device, taking care to minimize the capacitance of tracking. Stray capacitance (greater than 3 pF) reduces the switching frequency, or can sometimes stop the oscillator circuit. The maximum recommended voltage applied to the SYNC pin is 3.0 V.
For an application that uses more than eight synchronized devices, use an external device to drive the SYNC pins. The application report External Synchronization of the DCP01/02 Series of DC/DC Converters describes this configuration.
During the start-up period, all synchronized devices draw maximum current from the input simultaneously. If the input voltage falls below approximately 4 V, the devices may not start up. A 2.2-μF capacitor should be connected close to each device input pin.