SBASAZ0A August 2024 – December 2024 AMC0136
PRODUCTION DATA
Figure 7-1 shows a simplified schematic of a full-bridge motor drive that uses an AMC0136 to sense the 48V DC link voltage. The DC link voltage is divided down to a 1V level by the resistive divider consisting of R1 and RSNS. The AMC0136 digitizes the analog input signal on the high-side and transfers the data across the isolation barrier to the low-side. The device then outputs the digital bitstream on the DOUT pin that is synchronized to the clock applied to the CLKIN pin. The digital bitstream is processed by a low-pass digital filter in a micro control unit (MCU) or FPGA.
The motor current in this application is sensed by an AMC0106M05 isolated modulator.
The AMC0136 requires a 3.3V or 5V supply to power the high-side (AVDD) of the isolated modulator. In this example, AVDD is derived from the 48V rail by a DC/DC converter and a shunt regulator. The low-side supply (DVDD) is shared with circuitry in the signal domain. Use the optional 49.9Ω resistor on the DOUT pin for line-termination to improve signal integrity on the receiving end.
The galvanic isolation barrier and high common-mode transient immunity (CMTI) of the AMC0136 provide reliable and accurate operation even in high-noise environments.