HIP1012A

FN4419 Rev 6.00

Page 5 of 15

March 2004

HIP1012A Description and Operation

The HIP1012A is a multifeatured dual power supply distribution

controller, including programmable current limiting regulation

and time to latch off. Additionally the HIP1012A operates both

as a +3.3V and 5V or a +5V and +12V power supply controller

with each mode having appropriate UnderVoltage (UV) fault

notification levels.

Upon initial power up HIP1012A can either isolate the voltage

supply from the load by holding the external N-Channel

MOSFET switches off or apply the supply rail voltage directly

to the load for true hot swap capability. In either case the

HIP1012A turns on in a soft start mode protecting the supply

rail from sudden current loading. If either PWRON pin is

pulled low the HIP1012A will be in true hot swap mode. Both

PWRON pins must be high to turn off the HIP1012A thus

isolating the power supply from the load through the external

FETs.

At turn-on, the gate capacitor of each external N-Channel

MOSFET is charged with a 10

A current source. These

capacitors create a programmable ramp (soft turn-on). A

charge pump supplies the gate drive for the 12V supply switch

driving that gate to 17V.

The load currents pass through two external current sense

resistors. When the voltage across either resistor exceeds the

user programmed Overcurrent (OC) voltage threshold value,

(see Table 1) the controller enters current regulation. At this

current source and the controller enters the time out period.

The length of the time out period is set by the single external

ground and is characterized by a lowered gate drive voltage to

charges to 2V, an internal comparator is tripped resulting in

both N-Channel MOSFETs being latched off.

Gate Turn-On Current

8

10

12

A

3X Gate Discharge Current

3XdisI

0.5

0.75

-

A

5V Undervoltage Threshold

4.35

4.5

4.65

V

3.3V Undervoltage Threshold

2.65

2.8

2.95

V

3.3/5VG High Voltage

3/5VG

11.2

11.9

-

V

SUPPLY CURRENT AND IO SPECIFICATIONS

48

10

mA

9.5

10.0

10.7

V

9.3

9.8

10.3

V

Current Limit Time-Out

20

24

ms

PWRON Pull-up Voltage

PWRN_V

PWRON pin open

1.8

2.4

3.2

V

PWRON Rising Threshold

PWR_Vth

1.1

1.5

2

V

PWRON Hysteresis

PWR_hys

0.1

0.2

0.3

V

PWRON Pull-Up Current

PWRN_I

60

80

100

A

1.8

2

2.2

V

8

10

12

A

1.7

2.6

3.5

mA

3.5

5

6.5

mA

90

100

110

A

Charge Pump Output Current

Qpmp_Io

320

560

800

A

Charge Pump Output Voltage

Qpmp_Vo

No load

17.2

17.4

-

V

Charge Pump Output Voltage - Loaded

Qpmp_VIo

Load current = 100

A

16.2

16.7

-

V

Charge Pump POR Rising Threshold

Qpmp+Vth

15.6

16

16.5

V

Charge Pump POR Falling Threshold

Qpmp-Vth

15.2

15.7

16.2

V

Electrical Specifications

PARAMETER

SYMBOL

TEST CONDITIONS

MIN

TYP

MAX

UNITS