SBOSAF6 June 2024 TMCS1127
PRODUCTION DATA
The TMCS1127 only requires a power supply (VS) on the low-voltage isolated side, which powers the analog circuitry independent of the isolated current input. VS determines the full-scale output range of the analog output VOUT, and can be supplied with any voltage between 3V and 5.5V. To filter noise in the power-supply path, place a low-ESR decoupling capacitor of 0.1µF between VS and GND pins as close as possible to the supply and ground pins of the device. More decoupling capacitance can be added to compensate for noisy or high-impedance power supplies. When used in extremely noisy environments, ferrite beads can be added close to the supply pin as shown in Figure 9-4 to target and suppress high-frequency noise coupled on to system supply.
The TMCS1127 power supply VS can be sequenced independently of current flowing through the input. However, there is a power-on delay between VS reaching the recommended operating voltage and the analog output validation. During this power-on time, the output voltage VOUT can transition between GND and VS as the output transfers from a high impedance reset state to the active drive state. If this behavior must be avoided, then provide a stable supply voltage VS for longer than the power-on time prior to applying input current.