SMH4814
Preliminary Information
CONFIGURATION REGISTERS (CONTINUED)
Register R0D – Power Down or Forced Shutdown, Fault or no Fault
These bits control how the given inputs affect the power off.
Register R0D
D7
0
1
-
D6
D5
D4
-
D3
-
D2
-
D1
-
D0
-
Action
-
-
FB low w/ FET on: Power Down
-
-
-
-
-
-
-
FB low w/ FET on: Forced Shutdown
ENTS low w/ FET on: Power Down
ENTS low w/ FET on: Forced Shutdown
OV condition: Power Down
OV condition: Forced Shutdown
UV condition: Power Down
0
1
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
0
1
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
0
1
-
-
-
-
-
-
-
-
-
-
-
-
-
UV condition: Forced Shutdown
FB low w/ FET on: don’t set FAULT
FB low w/ FET on: set FAULT
ENTS low w/ FET on: don’t set FAULT
ENTS low w/ FET on: set FAULT
OV condition: don’t set FAULT
OV condition: set FAULT
-
-
0
1
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
0
1
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
0
1
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
0
1
UV condition: don’t set FAULT
UV condition: set FAULT
-
-
-
-
-
-
-
Register R0E – Slew Rate Control
Bits D[7:6] control the PUPD Time Slot. Bits D[5:4] control the PUPC Time Slot. Bits D[3:2] control the PUPB Time
Slot. Bits D[1:0] control the PUPA Time Slot.
Register R0E
D7
0
D6
D5
D4
D3
D2
D1
D0
Action
0
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
Scale Factor SLEW_CNTL to Curr. Reg. = 1/100
Scale Factor SLEW_CNTL to Curr. Reg. = 1/50
Scale Factor SLEW_CNTL to Curr. Reg. = 1/20
Scale Factor SLEW_CNTL to Curr. Reg. = 1/10
Use SLEW_CNTL for Current Regulation Voltage =
Curr. Reg. Voltage is fixed by registers R09 and R0A
Use SLEW_CNTL for Current Regulation Voltage =
Curr. Reg. Voltage = SLEW CNTL*scale factor D[7:6]
0
1
1
1
0
1
-
-
-
-
-
-
-
-
0
1
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
0
Use SLEW_CNTL for FET GATE Current Ramp =
FET GATE current is fixed at Max Current
Use SLEW_CNTL for FET GATE Current Ramp =
FET GATE current = (Max Current)*(SLEW CNTL)/2.5
-
1
-
Max FET GATE Current = (8+(n X 8))µA
Largest FET GATE Current = (8+(15 X 8)) = 136µA
-
-
-
1
1
1
1
0
0
0
1
0
1
-
-
-
-
-
-
-
-
0
1
Lowest FET GATE Current = (8+(0 X 8)) = 8µA
FET GATE Current = (8+(11 X 8)) = 96µA
Summit Microelectronics, Inc
2080 2.0 07/21/05
37