SNVS641L January 2010 – April 2019 LMZ10503
PRODUCTION DATA.
A resistor divider network from VOUT to the FB pin determines the desired output voltage as follows:
Rfbt is defined based on the voltage loop requirements and Rfbb is then selected for the desired output voltage. Resistors are normally selected as 0.5% or 1% tolerance. Higher accuracy resistors such as 0.1% are also available.
The feedback voltage (at VOUT = 2.5 V) is accurate to within –2.5% / +2.5% over temperature and over line and load regulation. Additionally, the LMZ10503 contains error nulling circuitry to substantially eliminate the feedback voltage variation over temperature as well as the long term aging effects of the internal amplifiers. In addition the zero nulling circuit dramatically reduces the 1/f noise of the bandgap amplifier and reference. The manifestation of this circuit action is that the duty cycle will have two slightly different but distinct operating points, each evident every other switching cycle.