HIP6014

FN4420 Rev.2.00

Page 6 of 12

March 2000

CSS charging interval and causes an over-current trip. The

converter dissipates very little power with this method. The

measured input power for the conditions of Figure 4 is 2.5W.

The over-current function will trip at a peak inductor current

(IPEAK) determined by:

where IOCSET is the internal OCSET current source (200A

typical). The OC trip point varies mainly due to the MOSFET’s

rDS(ON) variations. To avoid over-current tripping in the normal

operating load range, find the ROCSET resistor from the

equation above with:

1. The maximum rDS(ON) at the highest junction temperature.

2. The minimum IOCSET from the specification table.

3. Determine IPEAK for

,

where

I is the output inductor ripple current.

For an equation for the ripple current see the section under

component guidelines titled ‘Output Inductor Selection’.

A small ceramic capacitor should be placed in parallel with

ROCSET to smooth the voltage across ROCSET in the

presence of switching noise on the input voltage.

Output Voltage Program

The output voltage of a HIP6014 converter is programmed to

discrete levels between 1.8VDC and 3.5VDC. The voltage

identification (VID) pins program an internal voltage reference

(DACOUT) with a TTL-compatible 5-bit digital-to-analog

converter (DAC). The level of DACOUT also sets the PGOOD

and OVP thresholds. Table 1 specifies the DACOUT voltage

for the 32 different combinations of connections on the VID

pins. The output voltage should not be adjusted while the

converter is delivering power. Remove input power before

0A

0V

TIME (20ms/DIV.)

5A

10A

15A

2V

4V

FIGURE 4. OVER-CURRENT OPERATION

IPEAK

IOCSET ROCSET



rDS ON



---------------------------------------------------

=

IPEAK IOUT MAX



I

 2



+



TABLE 1. OUTPUT VOLTAGE PROGRAM

PIN NAME

NOMINAL OUTPUT

VOLTAGE DACOUT

PIN NAME

NOMINAL OUTPUT

VOLTAGE DACOUT

VID4

VID3

VID2

VID1

VID0

VID4

VID3

VID2

VID1

VID0

01

111

0

1

111

1

0

01

110

0

1

111

0

2.1

01

101

0

1

110

1

2.2

01

100

0

1

110

0

2.3

01

011

0

1

101

1

2.4

01

010

0

1

101

0

2.5

01

001

0

1

100

1

2.6

01

000

0

1

100

0

2.7

00

111

0

1

011

1

2.8

00

110

0

1

011

0

2.9

00

101

1.80

1

010

1

3.0

00

100

1.85

1

010

0

3.1

00

011

1.90

1

001

1

3.2

00

010

1.95

1

001

0

3.3

00

001

2.00

1

000

1

3.4

00

000

2.05

1

000

0

3.5

NOTE: 0 = connected to GND or VSS, 1 = connected to VDD through pull-up resistors