_:n7e334ecaea9542ab97a108c433993d9dxb2
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"Hi Tom, \n Yes, the 2977 is able to monitor and control eight power supplies. The chip only monitors DC voltages. Maybe you can provide more info on the AC/DC converter, or send a diagram. \n The &#39;control&#39; aspect is enabling and disabling the individual supplies. The supplies can be enabled/disabled either with a CONTROL pin, with a PMbus command, or it will just respond to Vin. The enable signal is a logic level signal. There&#39;s also a sequencer built into the 2977 that allows you to set the time when enables fires to each supply. \n The &#39;monitor&#39; aspect takes a bit more explanation, especially when high voltage is involved. The 2977 has eight voltage sensing pins, and the max voltage is limited to 6V. If you need to sense a 40V rail, you&#39;ll need to divide down 40V to something less than 6V to satisfy the 2977 ratings. This can be accomplished with a simple voltage divider, or with an op-amp that drives a single-ended voltage into the Vsense pin. The advantage of the op-amp is its low impedance output that drives Vsense. The resistor approach is fine but you need to select the values carefully, so as to avoid errors introduced due to Vsense pin current being injected into the divider. The demo board DC2518 covers some of these issues. \n When discussing HV power management, we will shortly introduce a 2-ch PSM that supports voltages as high as +/-60V. The part number is LTC2971. It controls and monitors 60V supplies and also measures output current. You would need four 2971 devices to monitor/measure 8 power supply rails. It also measures/monitors the input supply&#39;s voltage and current. \n Whether you use a single 2977 or multiple 2971, the supplies can be sequenced based on the timing settings that you set. A timing signal called SHARE_CLK is tied across all PSM devices and is used to synchronize the on/off delay times. \n I hope this gives better insight into the workings of a PSM device. \n Mike)"
<https://ez.analog.com/power/f/q-a/166969/ltc2977/378054>