JAJS234H MARCH 2007 – May 2019 TPS40192 , TPS40193
PRODUCTION DATA.
The input voltage ripple is divided between capacitance and ESR. For this design VRIPPLE(cap) = 400 mV and VRIPPLE(ESR) = 200 mV. Use Equation 14 to estimate the minimum capacitance and maximum ESR.
For this design CIN(min)> 9.375 μF and ESR < 17.7 mΩ . Use Equation 16 to estimate the RMS current in the input capacitors.
The total input capacitance must support 2.37 A of RMS ripple current.
Two 1210 10-μF, 25 V, X5R ceramic capacitors with approximately 2 mΩ ESR and a 2-ARMS current rating are selected. Higher voltage capacitors minimize capacitance loss at the DC bias voltage to ensure the capacitors have sufficient capacitance at the working voltage.