MIC3003 datasheet(53/75 Pages) MICREL

53 / 75 page

Micrel, Inc.

MIC3003

November 2009

M9999-111209-C

hbwhelp@micrel.com or (408) 955-1690

Power-On Hours (POHh and POHl)

D[7]

read/write

D[6]

read/write

D[5]

read/write

D[4]

read/write

D[3]

read/write

D[2]

read/write

D[1]

read/write

D[0]

read/write

Default value of both bytes when the

MIC3003 is shipped from the factory

0000 0000b = 00h

Serial address

A6h

Bytes addresses

MS byte (POHh): 251 = FBh

LS byte (POHl): 252 = FCh

The lower seven bits of POHh contain the most significant bits of the 15-bit power-on hours measurement. The value in POHh

should be combined with the eight-bit power-on hours low byte, POHl, to yield the complete result.

The most significant bit of POHh, POHFLT, is an error flag. If POHFLT is set, the power-on hour meter data has been

corrupted and should be ignored.

It is recommended that a two-byte sequential (block) SMBus read operation be performed on POHh and POHl to insure

coherency between the two registers.

This register is non-volatile and will be maintained through power and reset cycles, including unanticipated power failures.

POHh Bit(s)

Function

Operation

D[7]

Power-on hours fault flag, POHFLT

1 = fault: the power-on hours value is corrupted and cannot

be relied upon

0 = no fault: the power-on hours value is correct

D[6:0]

Power-on hours, most significant seven bits

Data Ready Flags (DATARDY)

D[7]

TRDY

read/write

D[6]

VRDY

read/write

D[5]

IRDY

read/write

D[4]

TXRDY

read/write

D[3]

RXDY

read/write

D[2]

reserved

D[1]

reserved

D[0]

reserved

Default value

0000 0000b = 00h

Serial address

A6h

Byte address

253 = FDh

When the A/D conversion for a given parameter is completed and the results available to the host, the appropriate data ready

flag will be set. The flag will be cleared when the host reads the corresponding result register.

Bit(s)

Function

Operation

D[7]

TRDY

Temperature data ready flag