MP8865

– SYNCHRONOUS STEP-DOWN CONVERTER

MP8865 Rev. 1.03

www.MonolithicPower.com

21

1/18/2018

MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.

© 2018 MPS. All Rights Reserved.

D[6:0]

VOUT

D[6:0]

VOUT

D[6:0]

VOUT

D[6:0]

VOUT

001 1101

0.89

011 1101

1.21

101 1101

1.53

111 1101

1.85

001 1110

0.90

011 1110

1.22

101 1110

1.54

111 1110

1.86

001 1111

0.91

011 1111

1.23

101 1111

1.55

111 1111

1.87

2. Reg01 SysCntlreg1

NAME

BITS

DEFAULT

DESCRIPTION

EN

D[7]

1

takes over.

The default EN bit is “1.”

GO_BIT

D[6]

0

reference. When the command is finished, GO_BIT will auto re-

set to “0”

to prevent false operation of VOUT scaling. If the reference is adjusted

within 50mV, GO_BIT will NOT auto re-set to

“0.” If this is the case,

manually set GO_BIT to

“0.” Writing GO_BIT=“1” first is suggested, then

write the output reference voltage.

Slew Rate

D[5:3]

100

D[5:3]

SLEW RATE

D[5:3]

SLEW RATE

000

64 mV/uS

100

4 mV/uS

001

32 mV/uS

101

2 mV/uS

010

16 mV/uS

110

1 mV/uS

011

8 mV/uS

111

0.5 mV/uS

Switching

Frequency

D[2:1]

00

D[2:1]

Fs

00

600kHz

01

850kHz

10

1.1MHz

11

1.6MHz

Mode

D0

0

“0” enables PFM mode; high disables PFM mode.

3. Reg02 ID1

NAME

BITS

DESCRIPTION

Vendor ID

D[7:4]

1000

IC Revision

D[3:0]

IC Revision

4. Reg03 Status

NAME

BITS

DESCRIPTION

Reserved

D[7:5]

Reserved for Future Use. Always set at 0.

VID_OK

D[4]

output with “VOUT” voltage. If “VOUT” is in the 90%-110% range of DAC output, the

VID_OK bit is high (which means the voltage scaling is finished). Otherwise,

VID_OK=”0.”

OC

D[3]

Output Over-Current Indication. When bit is high, the IC is in hiccup mode.

OTEW

D[2]

Die temperature early warning bit. When the bit is high, the die temperature is higher

than 120˚C.

OT

D[1]

Over-Temperature Indication. When the bit is high, the IC is in thermal shutdown.

PG

D[0]

Output Power Good Indication. When the bit is high, the VOUT power is good. This

means the VOUT is higher than 90% of the designed regulation voltage. See additional

details in the

“Power Good (PG) Indicator” section on page 15.