FAN5059

PRODUCT SPECIFICATION

2

REV. 1.0.4 8/14/03

currents in excess of 16A from a 5V source with minimal

external circuitry. Synchronous-mode operation offers opti-

mum efficiency over the entire specified output voltage range.

An on-board precision low TC reference achieves tight toler-

ance voltage regulation without expensive external compo-

tailoring of voltage for the most demanding load transients. The

FAN5059 includes linear regulator controllers for Vtt termina-

tion (1.5V), Vclock (2.5V), and Vnorthbridge (1.8V) or Vagp

(selectable 1.5V/3.3V), each adjustable with an external divider.

The FAN5059 also offers integrated functions including Power

Good, Output Enable/Soft Start and current limiting, and is

available in a 24 pin SOIC package.

Pin Assignments

24

23

22

21

20

19

18

17

16

15

14

13

FAN5059

HIDRV

SW

GNDA

VID4

VID3

VID2

VID1

VID0

VTTGATE

VTTFB

VCKGATE

VCKFB

VCCP

LODRV

GNDP

VCCA

VFB

DROOP

ILIM

PWRGD

SS/ENABLE

TYPEDET

VAGPGATE

VAGPFB

1

2

3

4

5

6

7

8

9

10

11

12

Pin Definitions

Pin

Number Pin Name

Pin Function Description

1

HIDRV

High Side FET Driver. Connect this pin through a resistor to the gate of an N-channel

MOSFET. The trace from this pin to the MOSFET gate should be <0.5".

2SW

High side Driver Source and Low side Driver Drain Switching Node. Together with

DROOP and ILIM pins allows FET sensing for Vcc current.

3

GNDA

Analog Ground. Return path for low power analog circuitry. This pin should be

connected to a low impedance system ground plane to minimize ground loops.

4-8

VID0-4

Voltage Identification Code Inputs. These open collector/TTL compatible inputs will

program the output voltage over the ranges specified in Table 2. Pull-up resistors are

internal to the controller.

9

VTTGATE

Gate Driver for VTT Transistor. For 1.5V output.

10

VTTFB

Voltage Feedback for VTT.

11

VCKGATE

Gate Driver for VCK Transistor. For 2.5V output.

12

VCKFB

Voltage Feedback for VCK.

13

VAGPFB

Voltage Feedback for VAGP.

14

VAGPGATE

Gate Driver for VAGP Transistor. For 3.3/1.5V output.

15

TYPEDET

Type Detect. Sets 3.3V or 1.5V for AGP.

16

ENABLE/SS

Output Enable. A logic LOW on this pin will disable all outputs. An internal current source

allows for open collector control. This pin also doubles as soft start for all outputs.

17

PWRGD

Power Good Flag. An open collector output that will be logic LOW if any output voltage

is more than ±12% outside of the nominal output voltage setpoint.

18

ILIM

Vcc Current Feedback. Pin 18 is used in conjunction with pin 2 as the input for the Vcc

current feedback control loop. Layout of these traces is critical to system performance.

See Application Information for details.

19

DROOP

Droop set. Use this pin to set magnitude of active droop.

20

VFB

Vcc Voltage Feedback. Pin 20 is used as the input for the Vcc voltage feedback control

loop. See Application Information for details regarding correct layout.

21

VCCA

Analog VCC. Connect to system 5V supply and decouple with a 0.1µF ceramic capacitor.

22

GNDP

Power Ground. Return pin for high currents flowing in pin 24 (VCCP).

23

LODRV

Vcc Low Side FET Driver. Connect this pin through a resistor to the gate of an N-channel

MOSFET for synchronous operation. The trace from this pin to the MOSFET gate should

be <0.5".

24

VCCP

Power VCC. For all FET drivers. Connect to system 12V supply through a 33

Ω, and

decouple with a 1µF ceramic capacitor.