ISL6112 Datasheet, PDF (19/31 Pages) Intersil Corporation – Dual Slot PCI-Express Power Controller

ISL6112
ISL6112 Register Set and Programmer’s Model
TABLE 4. ISL6112 REGISTER ADDRESSES
TARGET REGISTER
COMMAND BYTE VALUE
LABEL
DESCRIPTION
READ
WRITE
CNTRLA
Control Register Slot A
02h
02h
CNTRLB
Control Register Slot B
03h
03h
STATA
Slot A Status
04h
04h
STATB
Slot B Status
05h
05h
CS
Common Status Register
06h
06h
Reserved
Reserved/Do Not Use
07h - FFh
07h - FFh
POWER-ON
DEFAULT
00h
00h
00h
00h
xxxx 0000b
Undefined
Detailed Register Descriptions
Control Register, Slot A (CNTRLA)
8-Bits, Read/Write
TABLE 5. CONTROL REGISTER, SLOT A (CNTRLA)
D[7]
D[6]
D[5]
D[4]
D[3]
D[2]
read-only
read-only
read only
read only
read-only
read/write
AUXAPG
MAINAPG
Reserved
Reserved
Reserved
FORCE_A
ENABLE
D[1]
read/write
MAINA
D[0]
read/write
VAUXA
BIT(s)
AUXAPG
FUNCTION
AUX output power-good status, Slot A
MAINAPG MAIN output power-good status, Slot A
D[5]
Reserved
D[4]
Reserved
D[3]
Reserved
FORCE_A Allows or inhibits the operation of the FORCE_ONA input pin
ENABLE
MAINA
MAIN enable control, Slot A
VAUXA
VAUX enable control, Slot A
Power-Up Default Value:
Read Command_Byte Value (R/W):
0000 0000_b = 00_h
0000 0010_b = 02_h
OPERATION
1 = Power-is-Good (VAUXA Output is above its UVLO
threshold)
1 = Power-is-Good (MAINA Outputs are above their UVLO
thresholds)
Always read as zero
Always read as zero
Always read as zero
0 = FORCE_ONA is enabled
1 = FORCE_ONA is disabled
0 = Off, 1 = On
0 = Off, 1 = On
The power-up default value is 00_h. Slot is disabled upon power-up, i.e., all supply outputs are off.
NOTES:
6. The state of the PWRGDA pin is the logical AND of the values of the AUXAPG and the MAINAPG bits, except when FORCE_ONA is asserted.
If FORCE_ONA is asserted (the pin is pulled low), and FORCE_AENABLE is set to a logic zero, the PWRGDA pin will be unconditionally
forced to its open-drain (“Power Not Good”) state.
7. The values of the MAINAPG and AUXAPG register bits are not affected by FORCE_ONA, but will instead continue to read as high if power is
“Good,” and as low if the conditions which indicate that power is good are not met.
19
FN6456.0
September 28, 2007