VTT bus power supply analysis of Intel dual bridge main bridge.
Intel main board bus power supply mainly to the front-end bus (FSB) to provide pull-up stability between the CPU and the North Bridge chip signal transmission. The bus power supply often uses the operational amplifier to control the operation of the MOS tube, the memory power supply or bridge power supply depressurize to get 1.2 V power supply. A circuit that uses an operation plus a MOS tube to depress the generating bus to power the VTT_GMCH is shown in figure 1.
Figure 1 VTT_GMCH power generation circuit.
The 2_5LEVEL voltage is sent to the 5-pin of the operational amplifier LM324 by R223 and R209 partial voltage. The in-phase input voltage of the 5-pin operational amplifier is higher than that of the 6-pin invert output voltage, and the high-level signal is output at the 7-pin output end. After the resistor R58 was renamed N_GATE to the G pole of Q5, Q5 was switched on, and the DDR18V was reduced by Q5 to power the VTT_GMCH bus.
This article is from Allicdata Electronics Limited.