ir3082pbf International Rectifier Corp., ir3082pbf Datasheet - Page 12

• Manufacturer Part Number: ir3082pbf
• Description: Xphase Amd Opterontm/athlon 64tm Control Ic
• Manufacturer: International Rectifier Corp.

Adaptive Voltage Positioning
Adaptive voltage positioning is needed to reduce the output voltage deviations during load transients and the power
dissipation of the load when it is drawing maximum current. The circuitry related to voltage positioning is shown in
Figure 8. Resistor R
voltage. An internal current source whose value is programmed by the same external resistor that programs the
oscillator frequency pumps current into the FB pin. The error amp forces the converter’s output voltage lower to
maintain a balance at its inputs. R
DAC voltage.
Page 12 of 33
FB
is connected between the Error Amp’s inverting input pin FB and the converter’s output
FB
VID4
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
is selected to program the desired amount of fixed offset voltage below the
Note: 4 Output disabled (Fault mode)
VID3
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
VID2
Table 1 – VID Table
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
VID1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
VID0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
Vout (V)
1.550
1.525
1.500
1.475
1.450
1.425
1.400
1.375
1.350
1.325
1.300
1.275
1.250
1.225
1.200
1.175
1.150
1.125
1.100
1.075
1.050
1.025
1.000
0.975
0.950
0.925
0.900
0.875
0.850
0.825
0.800
OFF
4
IR3082PbF
01/31/05