SBAS994B September 2023 – September 2023 AMC131M03
PRODUCTION DATA
The AMC131M03 is powered from the low-side power supply (DVDD) with a nominal value of 3.3 V (or 5 V) ± 10%. Place a low-ESR decoupling capacitor of 1 nF (C15 in Figure 9-8) as close as possible to the DVDD pin, followed by a 1-µF capacitor (C16) to filter this power-supply path.
The low-side power supply (DVDD) is the only external supply required to operate the AMC131M03. All internal voltage supplies and secondary (high-side) supplies are generated by the integrated DC/DC converter and the high-side LDO, such as the supply voltage at the output pins, DCDC_OUT and HLDO_OUT.
The primary-side of the DC/DC converter is decoupled with a low-ESR, 100-nF capacitor (C17) positioned close to the device between the DCDC_CAP and DGND pins. Use a 1-µF capacitor (C6) to decouple the high-side in addition to a low-ESR, 1-nF capacitor (C1) placed as close as possible to the device and connected between the DCDC_OUT and DCDC_HGND pins.
For improved EMI performance, place a ferrite bead between the DCDC_OUT and HLDO_IN pins (F1) and the DCDC_HGND and HGND pins (F2), respectively.
For the high-side LDO, use low-ESR capacitors of 1 nF (C11) placed as close as possible to the AMC131M03, followed by a 100-nF decoupling capacitor (C13) between the HLDO_OUT and HGND pins.
The ground reference for the high-side (HGND) is derived from the terminal of the shunt resistor that is connected to the negative input (AIN0N) of the device. For best DC accuracy, use a separate trace to make this connection instead of shorting HGND to AIN0N directly at the device input.
Capacitors must provide adequate effective capacitance under the applicable DC bias conditions they experience in the application. MLCC capacitors typically exhibit only a fraction of the nominal capacitance under real-world conditions and this factor must be taken into consideration when selecting these capacitors. This problem is especially acute in low-profile capacitors, in which the dielectric field strength is higher than in taller components. Reputable capacitor manufacturers provide capacitance versus DC bias curves that greatly simplify component selection.
Table 9-3 lists components suitable for use with the AMC131M03. This list is not exhaustive. Other components can exist that are equally suitable (or better), however these listed components have been validated during the development of the AMC131M03.
COMP | DESCRIPTION | PART NUMBER | MANUFACTURER | SIZE (EIA, L x W) |
---|---|---|---|---|
DVDD | ||||
C15 | 1 nF ± 10%, X7R, 50 V | 12065C102KAT2A | AVX | 1206, 3.2 mm x 1.6 mm |
C16 | 1 µF ± 10%, X7R, 25 V | 12063C105KAT2A | AVX | 1206, 3.2 mm x 1.6 mm |
DC/DC CONVERTER | ||||
C17 | 100 nF ± 10%, X7R, 50 V | C0603C104K5RACAUTO | Kemet | 0603, 1.6 mm x 0.8 mm |
C1 | 1 nF ± 10%, X7R, 50 V | C0603C102K5RACTU | Kemet | 0603, 1.6 mm x 0.8 mm |
C6 | 1 µF ± 10%, X7R, 25 V | CGA3E1X7R1E105K080AC | TDK | 0603, 1.6 mm x 0.8 mm |
F1, F2 | Ferrite bead | 74269244182 | Wurth Elektronik | 0402, 1.0 mm x 0.5 mm |
HLDO | ||||
C24 | 100 nF ± 10%, X7R, 50 V | C0603C104K5RACAUTO | Kemet | 0603, 1.6 mm x 0.8 mm |
C10 | 1 nF ± 10%, X7R, 50 V | 12065C102KAT2A | AVX | 1206, 3.2 mm x 1.6 mm |
C13 | 100 nF ± 5%, NP0, 50 V | C3216NP01H104J160AA | TDK | 1206, 3.2 mm x 1.6 mm |
C11 | 1 nF ± 10%, X7R, 50 V | 12065C102KAT2A | AVX | 1206, 3.2 mm x 1.6 mm |