JAJSMN8D December 2000 – August 2021 DCR021205 , DCR022405
PRODUCTION DATA
When more than one DC/DC converter is switching in an application, 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 DCR02 series of devices overcome this interference by allowing devices to be synchronized 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 V.
For an application that uses more than eight synchronized devices use an external device to drive the SYNC pins. The External Synchronization of the DCP01/02 Series of DC/DC Converters Application Report (SBAA035) describes this configuration.
During the start-up period, all synchronized devices draw maximum current from the input simultaneously. A ceramic capacitor must be connected close to each device's input pin. A 2.2-µF ceramic capacitor is required.