ISL6504ACB-T - Intersil Corporation

FN9062.2

ISL6504, ISL6504A

Multiple Linear Power Controller with

ACPI Control Interface

The ISL6504 and ISL6504 A complement other power

building blocks (voltage regulators) in ACPI-compliant

designs for microprocessor and computer applications. The

IC integrates three linear controllers/regulators, switching,

monitoring and control functions into a 16-pin wide-body

SOIC or 20-pin QFN 6x6 package. The ISL6504, ISL6504A

operating mode (active outputs or sleep outputs) is

selectable through two digital control pins, S3 and S5.

One linear controller ge nerates the 3.3VDUAL/3.3VSB

voltage plane from the ATX supply’s 5VSB output, powering

the south bridge and the PCI slots through an external NPN

pass transistor during sleep states (S3, S4/S5). In active

state (during S0 and S1/S2), the 3.3VDUAL/3.3VSB linear

regulator uses an external N-channel pass MOSFET to

connect the outputs directly to the 3.3V input supplied by an

ATX power supply, for minimal losses.

A controller powers up the 5VDUAL plane by switching in the

ATX 5V output through an NMOS transistor in active states,

or by switching in the ATX 5VSB through a PMOS (or PNP)

transistor in S3 sleep state. In S4/S5 sleep states, the

ISL6504 5VDUAL outpu t is shut down. In the ISL6504A, the

5VDUAL output stays on during S4/S5 sleep states. This is

the only difference between the two parts; see Table 1.

An internal linear regulator supplies the 1.2V for the voltage

identification circuitry (VID) only during active states (S0 and

S1/S2), and uses the 3V3 pin as input source for its internal

pass element. Another intern al regulator outputs a 1.5VSB

chip-set standby supply, which uses the 3V3DL pin as input

source for its internal pass element. The 3.3VDUAL/3.3VSB

and 1.5V SB outputs are active for as long as the ATX 5VSB

voltage is applied to the chip.

Features

• Provides four ACPI-Controlled Voltages

-5V

DUAL USB/Keyboard/Mouse

-3.3V

DUAL/3.3VSB PCI/Auxiliary/LAN

-1.2V

VID Processor VID Circuitry

-1.5V

SB ICH4 Resume Well

• Excellent Output Voltage Regulation

- All Outputs: ±2.0% over temperature (as applicable)

• Small Size; Very Low External Component Count

• Undervoltage Monitoring of All Outputs with Centralized

FAULT Reporting and Temperature Shutdown

• QFN Package:

- Near Chip Scale Package Footprint; Improved PCB

Efficiency; Thinner profile

• Pb-Free Available (RoHS Compliant)

Applications

•ACPI-Compliant Power Regulation for Motherboards

- ISL6504: 5VDUAL is shut down in S4/S5 sleep states

- ISL6504A: 5VDUAL stays on in S4/S5 sleep states

Data Sheet April 13, 2004

CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.

1-888-INTERSIL or 321-724-7143 |Intersil (and design) is a registered trademark of Intersil Americas Inc.

All other trademarks mentioned are the property of their respective owners.

2FN9062.2

April 13, 2004

Pinouts ISL6504/A (WIDE BODY SOIC)

TOP VIEW

ISL6504/A (6X6 QFN)

TOP VIEW

3V3DLSB

3V3DL

1V2VID

3V3

1V5SB 5VSB

VID_PG

DLA

FAULT

5VDL

VID_CT

GND

5VDLSB

NOTE: SOIC layout should accomodate both wide and narrow footprints.

NOTE: The QFN bottom pad is electrically connected to the IC substrate, at

GND potential. It can be left unconnected, or connected to GND; do NOT

connect to another potential.

3V3DLSB

5VSB

1V5SB

VID_CT

GND

FAULT

DLA

3V3DL

1V2VID

3V3

VID_PG

5VDL

5VDLSB

678910

20 19 18 17 16

Ordering Information

PART NUMBER TEMP.

RANGE (oC) PACKAGE PKG.

DWG. #

ISL6504CB 0 to 70 16 Ld SOIC M16.3

ISL6504CBZ

(Note) 0 to 70 16 Ld SOIC

(Pb-free) M16.3

ISL6504CBN 0 to 70 16 Ld SOIC M16.15

ISL6504CBNZ

(Note) 0 to 70 16 Ld SOIC

(Pb-free) M16.15

ISL6504CR 0 to 70 20 Ld 6x6 QFN L20.6x6

ISL6504CRZ

(Note) 0 to 70 20 Ld 6x6 QFN

(Pb-free) L20.6x6

ISL6504EVAL1 Evaluation Board

ISL6504ACB 0 to 70 16 Ld SOIC M16.3

ISL6504ACBZ

(Note) 0 to 70 16 Ld SOIC

(Pb-free) M16.3

ISL6504ACBN 0 to 70 16 Ld SOIC M16.15

ISL6504ACBNZ

(Note) 0 to 70 16 Ld SOIC

(Pb-free) M16.15

ISL6504ACR 0 to 70 20 Ld 6x6 QFN L20.6x6

ISL6504ACRZ

(Note) 0 to 70 20 Ld 6x6 QFN

(Pb-free) L20.6x6

ISL6504AEVAL1 Evaluation Board

Add “-T” suffix for tape and reel.

NOTE: Intersil Pb-free products employ special Pb-free material

sets; molding compounds/die attach materials and 100% matte tin

plate termination finish, which are RoHS compliant and compatible

with both SnPb and Pb-free soldering operations. Intersil Pb-free

products are MSL classified at Pb-free peak reflow temperatures that

meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020.

ISL6504, ISL6504A

3FN9062.2

April 13, 2004

Block Diagram

5VSB

GND

4.4V/3.4V

5VSB POR

5VDLSB

3V3DL

FAULT UV DETECTOR

5VDL

EA4

3V3DLSB

UV COMP

4.10V

DLA

VID_PG

1V5SB

MONITOR AND CONTROL

1.265V

TEMPERATURE

MONITOR

(TMON)

1V2VID

TO 3V3

UV DETECTOR

EA3

TO UV

DETECTOR

EA3

S3 VID_CT

3V3

10mA

2.75V/2.60V

3V3 MONITOR

10mA

FIGURE 1.

ISL6504, ISL6504A

4FN9062.2

April 13, 2004

Simplified Power System Diagram

Typical Application

+5VSB

ISL6504/A

+3.3VIN

+12VIN

+5VIN

3.3VDUAL /3.3VSB

5VDUAL

CONTROL

LOGIC

LINEAR

CONTROLLER

FAULT

SHUTDOWN

1.2VVID

LINEAR

REGULATOR LINEAR

REGULATOR 1.2V

3.3V

1.5VSB

1.5V

VID_PG

FIGURE 2.

GND

5VSB

+3.3VIN

+5VSB

VID_PG

VID_CT

1V5SB

CCT_VID

ISL6504/A

+12VIN

VID PGOOD

SLP_S3 S3

VOUT3

3.3VDUAL/3.3VSB COUT3

+5VIN

COUT4

VOUT4

5VDUAL

3V3DL

3V3DLSB

DLA

5VDLSB

FAULT

5VDL

1V2VID

SHUTDOWN

FAULT

VOUT1

1.5VSB VOUT2

1.2VVID

COUT1

COUT2

SLP_S5 S5

CSS

3V3

RDLA

FIGURE 3.

ISL6504, ISL6504A

5FN9062.2

April 13, 2004

Absolute Maximum Ratings Thermal Information

Supply Voltage, V5VSB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +7.0V

DLA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GND - 0.3V to +14.5V

All Other Pins. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .+ 7.0V

ESD Classification (Human Body Model) . . . . . . . . . . . . . . . . . .2kV

Recommended Operating Conditions

Supply Voltage, V5VSB . . . . . . . . . . . . . . . . . . . . . . . . . . . +5V ±5%

Lowest 5VSB Supply Voltage Guaranteeing Parameters . . . . +4.5V

Digital Inputs, VSx . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0 to +5.5V

Ambient Temperature Range. . . . . . . . . . . . . . . . . . . . . 0oC to 70oC

Junction Temperature Range . . . . . . . . . . . . . . . . . . . 0oC to 125oC

Thermal Resistance (Typical) θJA (oC/W) θJC (oC/W)

SOIC Package (Note 1) . . . . . . . . . . . 70 N/A

QFN Package (Note 2) . . . . . . . . . . . . 32 4.0

Maximum Junction Temperature (Plastic Package) . . . . . . . .150oC

Maximum Storage Temperature Range . . . . . . . . . -65oC to 150oC

Maximum Lead Temperature (Soldering 10s). . . . . . . . . . . . .300oC

(SOIC - Lead Tips Only)

For Recommended soldering conditions see Tech Brief TB389.

CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation of the

device at these or any other conditions above those indicated in the operational sections of this specification is not implied.

NOTE:

1. θJA is measured with the component mounted on a high effective thermal conductivity test board in free air. See T ech Brief TB379 for details.

2. θJA is measured in free air with the component mounted on a high effective thermal conductivity test board with “direct attach” features. θJC, the

“case temp” is measured at the center of the exposed metal pad on the package underside. See Tech Brief TB379.

Electrical Specifications Recommended Operating Conditions, Unless Otherwise Noted Refer to Figures 1, 2 and 3

PARAMETER SYMBOL TEST CONDITIONS MIN TYP MAX UNITS

VCC SUPPLY CURRENT

Nominal Supply Current I5VSB -17- mA

Shutdown Supply Current I5VSB(OFF) VSS = 0.8V - 4 - mA

POWER-ON RESET, SOFT-START, AND VOLTAGE MONITORS

Rising 5VSB POR Threshold --4.5V

5VSB POR Hysteresis -0.9- V

Rising 3V3 Threshold -2.75- V

3V3 Hysteresis - 150 - mV

Falling Threshold Timeout (All Monitors) -10- µs

Soft-Start Current ISS -10- µA

Shutdown Voltage Threshold VSD --0.8V

VID_PG Rising Threshold -1.02- V

VID_PG Hysteresis -56- mV

1.5VSB LINEAR REGULATOR (VOUT1)

Regulation --2.0%

1V5SB Nominal Voltage Level V1V5SB -1.5- V

1V5SB Undervoltage Rising Threshold -1.25- V

1V5SB Undervoltage Hysteresis -75- mV

1V5SB Output Current I1V5SB V3V3DL = 3.3V 85 - - mA

1.2VVID LINEAR REGULATOR (VOUT2)

Regulation --2.0%

1V2VID Nominal Voltage Level V1V2VID -1.2- V

1V2VID Undervoltage Rising Threshold -0.96- V

1V2VID Undervoltage Hysteresis -60- mV

1V2VID Output Current I1V2VID V3V3 = 3.3V 40 - - mA

ISL6504, ISL6504A

6FN9062.2

April 13, 2004

3.3VDUAL/3.3VSB LINEAR REGULATOR (VOUT3)

Sleep State Regulation --2.0%

3V3DL Nominal Voltage Level V3V3DL -3.3- V

3V3DL Undervoltage Rising Threshold -2.75- V

3V3DL Undervoltage Hysteresis - 150 - mV

3V3DLSB Output Drive Current I3V3DLSB V5VSB = 5V 5 8 - mA

5VDUAL SWITCH CONTROLLER (VOUT4)

5VDL Undervoltage Rising Threshold -4.10- V

5VDL Undervoltage Hysteresis - 200 - mV

5VDLSB Output Drive Current I5VDLSB V5VDLSB = 4V, V5VSB = 5V -20 - -40 mA

TIMING INTERVALS

Active State Assessment Past Input UV

Thresholds (Note 3) 20 25 30 ms

Active-to-Sleep Control Input Delay - 200 - µs

VID_CT Charging Current IVID_CT VVID_CT = 0V - 10 - µA

CONTROL I/O (S3, S5, FAULT)

High Level Input Threshold --2.2V

Low Level Input Threshold 0.8 - - V

S3, S5 Internal Pull-up Impedance to 5VSB - 50 - kΩ

FAULT Output Impedance FAULT = high - 100 - Ω

TEMPERATURE MONITOR

Fault-Level Threshold (Note 4) 125 - - oC

Shutdown-Level Threshold (Note 4) - 155 - oC

NOTES:

3. Guaranteed by Correlation.

4. Guaranteed by Design.

Electrical Specifications Recommended Operating Conditions, Unless Otherwise Noted Refer to Figures 1, 2 and 3 (Continued)

PARAMETER SYMBOL TEST CONDITIONS MIN TYP MAX UNITS

ISL6504, ISL6504A

7FN9062.2

April 13, 2004

Functional Pin Description (SOIC pinout)

3V3 (Pin 5)

Connect this pin to the ATX 3.3V output. This pin provides

the output current for the 1V2VID pin, and is monitored for

power quality.

5VSB (Pin 16)

Provide a very well de-coupled 5V bias supply for the IC to

this pin by connecting it to the ATX 5VSB output. This pin

provides all the chip’s bias as well as the base current for Q2

(see typical application diagram). The voltage at this pin is

monitored for power-on reset (POR) purposes.

GND (Pin 8)

Signal ground for the IC. All volta ge levels are measured

with respect to this pin.

S3 and S5 (Pins 6 and 7)

These pins switch the IC’s operating state from active (S0,

S1/S2) to S3 and S4/S5 sleep states. These are digital

inputs featuring internal 50kΩ (typical) resistor pull-ups to

5VSB. Internal circuitry de-glitches these pins for

disturbances lasting as long as 2µs (typically). Additional

circuitry blocks any illegal state transitions (such as S3 to

S4/S5 or vice versa). Respectively, connect S3 and S5 to

the computer system’s SLP_S3 and SLP_S5 signals.

FAULT (Pin 9)

In case of an undervoltage on any of the controlled outputs,

on any of the monitored ATX voltages, or in case of an

overtemperature event, this pin is used to report the fault

condition by being pulled to 5VSB. Connect a 1kΩ resistor

from this pin to GND.

SS (Pin 13)

Connect this pin to a small ceramic capacitor (no less than

5nF; 0.1µF recommended). The internal soft-start (SS)

current source along with the external cap acitor creates a

voltage ramp used to control the ramp-up of the output

voltages. Pulling this pin low with an open-drain device shuts

down all the outputs as well as force the FAULT pin low. The

CSS capacitor is also used to provide a controlled voltage

slew rate during active-to-sleep transitions on the

3.3VDUAL/3.3VSB output.

3V3DL (Pin 3)

Connect this pin to the 3.3V dual/stand-by output (VOUT3).

In sleep states, the voltage at this pin is regulated to 3.3V; in

active states, ATX 3.3V output is delivered to this node

through a fully-on N-MOS transistor. Durin g all operating

states, this pin is monitored for undervoltage events. This pin

provides all the output current delivered by the 1V5SB pin .

3V3DLSB (Pin 2)

Connect this pin to the base of a suitable NPN transistor. In

sleep state, this transistor is used to regulate the voltage at

the 3V3DL pin to 3.3V.

DLA (Pin 10)

This pin is an open-collector output. Connect a 1kΩ resistor

from this pin to the ATX 12V output. This resistor is used to

pull the gates of suitable N-MOSFETs to 12V, which in

active state, switch in the ATX 3.3V and 5V outputs into the

3.3VDUAL/3.3VSB and 5VDUAL outputs, respectively.

5VDL (Pin 12)

Connect this pin to the 5VDUAL output (VOUT4). In either

operating state (when on), the voltage at this pin is provided

through a fully-on MOS transistor. This pin is also monitored

for undervoltage events.

5VDLSB (Pin 11)

Connect this pin to the gate of a suitable P-MOSFET or

bipolar PNP. ISL6504: In S3 sleep state, this tran sistor is

switched on, connecting the ATX 5VSB output to the

5VDUAL regulator ou tput. ISL6504A: In S3 and S4/S5 sl eep

state, this transistor is switched on, connecting the ATX

5VSB output to the 5VDUAL regulator output.

1V5SB (Pin 1)

This pin is the output of the internal 1.5V regulator (VOUT1).

This internal regulator operates for as lon g as 5VSB is

applied to the IC and draws its output current from the

3V3DL pin. This pin is monitored for undervoltage events.

1V2VID (Pin 4)

This pin is the output of the internal 1.2V voltage

identification (VID) regulator (VOUT2). This internal regulator

operates only in active states (S0, S1/S2) and is shut off

during any sleep state. This regulator draws its output

current from the 3V3 pin. This pin is monitored for

undervoltage events.

VID_PG (Pin 14)

This pin is the open collector output of the 1V2VID power

good comparator. Connect a 10kΩ pull-up resistor from this

pin to the 1V2VID output. As long as the 1V2VID output is

below its UV threshold, this pin is pulled low.

VID_CT (Pin 15)

Connect a small capacitor from this pin to ground. The

capacitor is used to delay the VID_PG reporting the 1V2VID

has reached power good l imits.

Description

Operation

The ISL6504/A controls 4 output voltages (Refer to Figures

1, 2, and 3). It is designed for microprocessor computer

applications with 3.3V, 5V, 5VSB, and 12V bias input from an

ATX power supply. The IC is composed of three linear

controllers/regulators supplying the computer system’s

1.5VSB (VOUT1), 3.3VSB and PCI slots’ 3.3VAUX power

(VOUT3), the 1.2V VID circui try power (VOUT2), a dual

switch controller supplying the 5VDUAL voltag e (V OUT4), as

ISL6504, ISL6504A

8FN9062.2

April 13, 2004

well as all the control and monitoring functions necessary for

complete ACPI implementation.

Initialization

The ISL6504/A automatically initializes upon receipt of input

power. The Power-On Reset (POR) function continually

monitors the 5VSB input supply voltage, initiating

3.3VDUAL/3.3VSB and 1.5VSB soft-start operation shortly

after exceeding POR threshold.

Dual Outputs Operational Truth Table

Table 1 describes the truth combinations pe rtaining to the

3.3VDUAL/SB and 5VDUAL outputs. The last two lines

highlight the only difference between th e ISL6504 and

ISL6504A. The internal circuitry does not allow the transition

from an S3 (suspend to RAM) state to an S4/S5 (suspend to

disk/soft off) state or vice versa. The only ‘legal’ transitions

are from an active state (S0, S1) to a sleep state (S3, S5)

and vice versa.

Functional Timing Diagrams

Figures 4 (ISL6504), 5 (ISL6504A), and 6 are timing diagrams,

detailing the power up/down sequences of all the outputs in

response to the status of the sleep-state pins (S3, S5), as well

as the status of the input ATX supply. Not shown in these

diagrams is the deglitching feature used to protect against false

sleep state tripping. Both S3 and S5 pins are protected against

noise by a 2µs filter (typically 1–4µs). This feature is useful in

noisy computer environments if the control signals have to

travel over significant distances. Additionally, the S3 pin

features a 200µs delay in transitioning to sleep states. Once the

S3 pin goes low, an internal timer is activated. At the end of

the 200µs interval, if the S5 pin is low, the ISL6504 /A

switches into S5 sleep state; if the S5 pin is high, the

ISL6504/A goes into S3 sleep state.

TABLE 1. 5VDUAL OUTPUT (VOUT4) TRUTH TABLE

S5 S3 3.3VDL/SB 5VDL COMMENTS

1 1 3.3V 5V S0/S1/S2 States (Active)

1 0 3.3V 5V S3

0 1 Note Maintains Previous State

0 0 3.3V 0V S4/S5 (ISL6504)

0 0 3.3V 5V S4/S5 (ISL6504A)

NOTE: Combination Not Allowed.

FIGURE 4. 5VDUAL AND 3.3VDUAL/3.3VSB TIMING

DIAGRAM; ISL6504

5VSB

3.3V, 5V

5VDLSB

DLA

3V3DLSB

3V3DL

5VDL

FIGURE 5. 5VDUAL AND 3.3VDUAL/3.3VSB TIMING

DIAGRAM; ISL6504A

5VSB

3.3V, 5V

5VDLSB

DLA

3V3DLSB

3V3DL

5VDL

FIGURE 6. 1.5VSB, AND 1.2VVID TIMING DIAGRAM

5VSB

3.3V,

1V2VID

DLA

1V5SB

5V, 12V

ISL6504, ISL6504A

9FN9062.2

April 13, 2004

Soft-Start into Sleep States (S3, S4/S5)

The 5VSB POR function initiates the soft-start sequence. An

internal 10µA current source charges an external capacitor.

The error amplifiers reference inputs are clamped to a level

proportional to the SS (soft-start) pin voltage. As the SS pin

voltage slews from about 1.25V to 2.5V, the input clamp

allows a rapid and controlled output voltage rise.

Figures 7 (ISL6504) and 8 (ISL6504A) show the soft-start

sequence for the typical application start-up into a sleep

state. At ti me T0 5VSB (bias) is applied to the circuit. At time

T1, the 5VSB surpasses POR level. An internal fast charge

circuit quickly raises the SS capacitor voltage to

approximately 1V, then the 10µA current source continues

the charging.

The soft-start capacitor voltage reaches approximately

1.25V at time T2, at which point the 3.3VDUAL/3.3VSB and

1.5VSB error amplifiers’ reference inputs start their

transition, resulting in the output voltages ramping up

proportionally. The ramp-up continues until time T3 when the

two voltages reach the set value. As the soft-start capacitor

voltage reaches approximately 2.75 V, the undervoltage

monitoring circuit of this output is activated and the soft-start

capacitor is quickly discharged to approximately 1.25V.

Following the 3ms (typical) time-out between T3 and T4, the

soft-start capacitor commences a second ramp-up designed

to smoothly bring up the remainder of th e voltages required

by the system. At time T5, voltages are within regulation

limits, and as the SS voltage reaches 2.75V, all the

remaining UV monitors are activated and the SS capacitor is

quickly discharged to 1.25V, where it remains until the next

transitio n. As the 1. 2VVID output is only active while in an

active state, it does not come up, but rather waits until the

main ATX outputs come up within regulation limits.

Soft-Start into Active States (S0, S1)

If both S3 and S5 are logic high at the time the 5VSB is

applied, the ISL6504/A will assume active state wake-up and

keep off the required outputs until some time (typically

25ms) after the monito red main ATX output (3.3V) exceeds

the set threshold. This time-out feature is necessary in order

to ensure the main ATX outputs are stabilized. The time-out

also assures smooth transitions from sleep into active when

sleep states are being supported. 3.3VDUAL/3.3VSB and

1.5VSB outputs will come up right after bias voltage

surpasses POR level.

TIME

SOFT-START

(1V/DIV)

OUTPUT

(1V/DIV)

VOLTAGES

VOUT1 (1.5VSB)

VOUT4 (5VDUAL) IF S3

T1 T2 T3

5VSB

(1V/DIV)

VOUT3 (3.3VDUAL/3.3VSB)

VOUT2

(1.2VVID)

VOUT4 (5VDUAL) if S5

FIGURE 7. SOFT-START INTERVAL IN A SLEEP

STATE; ISL6504

SOFT-START

(1V/DIV)

OUTPUT

(1V/DIV)

VOLTAGES VOUT1 (1.5VSB)

VOUT4 (5VDUAL)

T1 T2 T3

5VSB

(1V/DIV)

VOUT3 (3.3VDUAL/3.3VSB)

VOUT2

(1.2VVID)

FIGURE 8. SOFT-START INTERVAL IN A SLEEP

STATE; ISL6054A

TIME

ISL6504, ISL6504A

10 FN9062.2

April 13, 2004

During sleep-to-active state transitions from conditions

where the 5VDUAL output is initially 0V (such as S5 to S0

transition, or simple power-up sequence directly into active

state), the circuit goes through a quasi soft-start, the

5VDUAL output being pulled high through the body diode of

the N-Channel MOSFET connec ted between it and the 5V

ATX. Figure 9 exemplifies this start-up case. 5VSB is already

present when the main ATX outpu ts are turned on, at time

T0. As a result of +5VIN ramping up, the 5VDUAL output

capacitors charge up through the body diode of Q4 (see

Typical Application). At time T1, all main ATX outputs

exceed the ISL6504/A’s undervoltage thresholds, and the

internal 25ms (typical) timer is initiated. At T2, the time-out

initiates a soft-start, and the 1.2V voltage ID output is

ramped-up, reaching regulation limits at time T3.

Simultaneous with the beginning of this ramp-up, at time T2,

the DLA pin is released, allowing the pull-up resistor to turn

on Q2 and Q4, and bring the 5VDUAL output in regulation.

Shortly after time T3, as the SS voltage reaches 2.75V, the

soft-start capacitor is quickly discharged down to

approximately 2.45V, where it remains until a valid sleep

state request is received from the system.

Fault Protection

All the outputs are monitored against undervoltage events. A

severe overcurrent caused by a failed load on an y of th e

outputs, would, in turn, cause that specific output to

suddenly drop. If any of the output voltages drops below

80% (typical) of their set value, such event is reported by

having the FAULT pin pulled to 5V. Additionally, exceeding

the maximum current rating of an integrated regulator

(output with pass regulator on chip) can lead to output

voltage drooping; if excessive, this droop ca n ultimately trip

the undervoltage detector and send a FAULT signal to the

computer system.

A FAULT condition occurring on an output when controlled

through an external pass transistor will only set off the

FAULT flag, and it will not shut off or latch off any part of the

circuit. A FAULT condition occurring on an output controlled

through an internal pass transistor, will set off the FAULT

flag, and it will shut off the respective faulting regulator only.

If shutdown or latch off of the entire circuit is desired in case

of a fault, regardless of the cause, this can be achieved by

externally pulling or latching the SS pin low. Pulling the SS

pin low will also force the FAULT pin to go low and reset any

internally latched-off outpu t.

Special consideration is given to the initial start-up

sequence. If, following a 5VSB POR event, any of the

1.5VSB or 3.3VDUAL/3.3VSB outputs is ramped up and is

subject to an undervoltage event before the end of the

second soft-start ramp, then the FAULT output goes high

and the entire IC latches off. Latch-off condition can be reset

by cycling the bias power (5VSB). Undervoltage events on

the 1.5VSB and the 3.3VDUAL/3.3VSB outputs at any other

times are handled according to the description found in the

second paragraph under the current heading.

Another condition that could set off the FAULT flag is chip

overtemperature. If the ISL6504/A reaches an internal

temperature of 140oC (typical), the FAULT flag is set, but the

chip continues to operate until the temperature reaches

155oC (typical), when unconditional shu tdo wn of all outputs

takes place. Operation resumes only after po wering down

the IC (to create a 5VSB POR event) and a start-up

(assuming the cause of the fault has been removed; if not,

as it heats up again, it will repeat the FAULT cycle).

In ISL6504/A applications, loss of the active ATX output

(3.3VIN; as detected by the on-board voltage monitor) during

active state operation causes the chip to switch to S5 sleep

state, in addition to reporting the input UV condition on the

FAULT pin. Exiting from this forced S5 state can only be

achieved by returning the faulting input voltage above its UV

threshold, by re set ti n g th e chip through removal of 5VSB

bias voltage, or by bringing the SS pin at a potential lower

than 0.8V.

Application Guidelines

Soft-Start Interval

The 5VSB output of a typical ATX supply is capable of

725mA, with newer models rated for 1.0A, and even 2.0A.

During power-up in a sleep state, the 5VSB ATX outp ut

needs to provide sufficient current to charge up all the

applicable output capacitors and, simultaneously, provide

some amount of current to the output loads. Drawing

FIGURE 9. SOFT-START INTERVAL IN ACTIVE STATE

TIME

OUTPUT

(1V/DIV)

VOLTAGES

T1 T2 T3

INPUT VOLTAGES

(2V/DIV)

+5VIN

+12VIN

+5VSB

VOUT1 (1.5VSB)

VOUT3 (3.3VDUAL/3.3VSB)

VOUT4 (5VDUAL)

DLA PIN

(2V/DIV)

+3.3VIN

VOUT2 (1.2VVID)

SOFT-START

(1V/DIV)

ISL6504, ISL6504A

11 FN9062.2

April 13, 2004

excessive amounts of current from the 5VSB output of the

ATX can lead to voltage collapse and induce a pattern of

consecutive restarts with unknown effects on the system’s

behavior or health.

The built-in soft-start circuitry allows tight control of the slew-

up speed of the output voltages controlle d by the ISL6504,

thus enabling power-ups free of supply drop-off events.

Since the outputs are ramped up in a linear fashion, the

current dedicated to charging the output capacitors can be

calculated with the following formula:

, where

ISS - soft-start current (typically 10µA)

CSS - soft-start capacitor

VBG - bandgap voltage (typically 1.26 V)

Σ(COUT x VOUT) - sum of the products between the

capacitance and the voltage of an output (total charge

delivered to all outputs)

Due to the various system timing events and their

interaction, it is recommended that the soft-start interval not

be set to exceed 30ms. For most applications, a 0.1µF

capacitor is recommended.

Shutdown

In case of a FAULT condition that might endanger the

computer system, or at any other time, all the ISL6504/A

outputs can be shut down by pulling the SS pin below the

specified shutdown level (typically 0.8V) with an open drain

or open collector device capable of sinking a minimum of

2mA. Pulling the SS pin low effectively shuts down all the

pass elements. Upon release of the SS pin, the ISL6504

undergoes a new soft-start cycle and resumes normal

operation in accordance to the ATX suppl y and control pins

status.

VID_PG Delay

During power-up and initial soft-start, the VID_PG and

VID_CT pins are held low. As the 1V2VID output exceeds its

rising power-good threshold, the capacitor connected at the

VID_CT pin starts to charge up through the internal 10 µA

current source. As the voltage on this capacitor exceeds

1.25V, the open-collector VID_PG pin is released and VID

POWER GOOD status is thus reported.

The value of the VID_CT capa citor to be used to obtain a

given VID_PG delay can be determined from the graph in

Figure 10. For extended delays exceed ing the range of the

graph, use the following formula:

, where

tDELAY - desired delay time (s)

C - VID_CT capacitor to obtain desired delay time (F)

Layout Considerations

The typical application employing an ISL6504/A is a fairly

straight forward implementation. Like with any other linear

regulator, attention has to be paid to the few potentially

sensitive small signal components, such as those connected

to sensitive nodes or those supplying critical bypass current.

The power components (pass transistors) and the controller

IC should be placed first. The controller should be placed in

a central position on the motherboard, closer to the memory

controller chip and processor, but not excessively far from

the 3.3VDUAL island or the I/O circuitry. Ensure the 1V5SB,

1V2VID, 3V3, and 3V3DL connections are properly sized to

carry 100mA without exhibiting significant resistive losses at

the load end. Similarly, the input bi as supply (5VSB) can

carry a significant level of current - for best results, ensure it

is connected to its respective source through an adequately

sized trace. The pass transistors should be placed on pads

capable of heatsinking matching the device’s power

dissipation. Where applicable, multiple via connections to a

large internal plane can significantly lower localized device

temperature rise.

Placement of the decoupling and bulk capaci tors shou ld

follow a plac e m en t refl e c ti ng th ei r pu rp o s e. As such, the

high-frequency decoupling capacitors should be placed as

close as possible to the load they are decoupling ; the one s

decoupling the controller close to the controller pins, the

ones decoupling the load close to the load conne ctor or the

load itself (if embedded). Even though bulk capa citance

(aluminum electrolytics or tantalum capacitors) placement is

not as critical as the high-frequency capacitor placement,

having these capacitors close to the load they serve is

preferable.

The critical small sign al components include the soft-start

capacitor, CSS, as well as all the high-frequency decoupling

capacitors. Locate these components close to the respective

ICOUT ISS

CSS VBG

------------------------------ΣCOUT VOUT

×()×=

CtDELAY

125000

--------------------=

C (nF)

FIGURE 10. VID_PG DELAY DEPENDENCE ON VID_CT

CAPACITOR

VID_PG Delay (ms)

012345678910

ISL6504, ISL6504A

12 FN9062.2

April 13, 2004

pins of the control IC, and connect them to ground through a

via placed close to the ground pad. Minimize any leakage

current paths from the SS node, as the internal current

source is only 10µA (typical).

A multi-layer printed circuit board is recommended.

Figure 11 shows the connections to most of the components

in the circuit. Note that the individual capacitors shown each

could represent numerous physical capacitors. Dedicate one

solid layer for a ground plane and make all critical

component ground connections through vias placed as close

to the component terminal as possible. Dedicate another

solid layer as a power plane and break this plane into

smaller islands of common voltage levels. Ideally, the power

plane should support both the input power and output power

nodes. Use copper filled polygo ns on the top and bottom

circuit layers to create power islands connecting the filtering

components (output capacitors) and the loads. Use the

remaining printed circuit layers for small signal wiring.

Component Selection Guidelines

Output Capacitors Selection

The output capacitors should be selected to allow the output

voltage to meet the dynamic regulation requirements of

active state operation (S0, S1). The load transient for the

various microprocessor system’s components may require

high quality capacitors to supply the high slew ra te (di/dt)

current demands. Thus, it is recommended that the output

capacitors be selected for transient load regulation, paying

attention to their parasitic components (ESR, ESL).

Also, during the transition between active and sleep states

on the 3.3VDUAL/3.3VSB and 5VDUAL outputs, there is a

short interval of time during which none of the power pass

elements are conducting - during this time the output

capacitors have to supply all the output current. The output

voltage drop during this brief period of time can be ea sily

approximated with the following formula:

, where

∆VOUT - output voltage drop

ESROUT - output capacitor ba nk ESR

IOUT - output current during transition

COUT - output capacitor bank capacitance

tt - active-to-slee p or sleep-to-a ctive transition time (10µs typ.)

The output voltage drop is heavily dependent on the ESR

(equivalent series resistance) of the output capacitor bank,

the choice of capacitors should be such as to maintain the

output voltage above the lowest allowable regulation level.

Input Capacitors Selection

The input capacitors for an ISL6504/A application must have

a sufficiently low ESR so as not to allow the input voltage to

dip excessively when energy is transferred to the output

capacitors. If the ATX supply does not meet the

specifications, certain imbalances between the ATX’s

outputs and the ISL6504/A’s regulation levels could have as

a result a brisk transfer of energy from the input capacitors to

the supplied outputs. At the transition between active and

sleep states, such phenomena could be responsible for the

5VSB voltage drooping excessively and affecting the output

regulation. The solution to such a potential problem is using

larger input capacitors with a lower total combined ESR.

Transistor Selection/Considerations

The ISL6504/A usually requires one P-Channel (or bipolar

PNP), two N-Channel MOSFETs, and one bipolar NPN

transistors.

One important criteria for selection of transistors for all the

linear regulators/switching elements is package selection for

efficient removal of heat. The power dissipated in a linear

regulator or an ON/OFF switching element is

Select a package and heatsink that maintains the junction

temperature below the rating with the maximum expected

ambient temperature.

LOAD

VOUT1

CHF1

LOAD

FIGURE 11. PRINTED CIRCUIT BOARD ISLANDS

VOUT3

CSS

+12VIN

CIN

VIA CONNECTION TO GROUND PLANE

ISLAND ON POWER PLANE LAYER

ISLAND ON CIRCUIT/POWER PLANE LAYER

ISL6504/A

VOUT4

GND

5VDLSB

3V3DLSB

KEY

5VSB

+5VSB

DLA Q4

CBULK4

LOAD

C5VSB

LOAD

CHF3

CHF4

5VDL

+5VIN

+3.3VIN

3V3DL

3V3

1V5SB

CBULK2

CHF2

CBULK1

1V2VID

CBULK3

VOUT2

VOUT

∆IOUT ESROUT tt

COUT

----------------+







×=

PLINEAR IOVIN VOUT

–()×=

ISL6504, ISL6504A

13 FN9062.2

April 13, 2004

The NPN transistor used as sleep state pass element on the

3.3VDUAL output has to have a minimum current gain of 100

at 1.5V VCE and 650mA ICE throughout the in-circuit

operating temperature range. For larger current ratings on

the 3.3VDUAL output (providing the ATX 5VSB output rating

is equally extended), selection criteria for Q1 include an

appropriate current gain (hfe) and saturation characteristics.

Q2, Q4

These N-Channel MOSFETs are used to switch the 3.3V

and 5V inputs provided by the ATX supply into the

3.3VDUAL/3.3VSB and 5VDUAL outputs while in active (S0,

S1) state. The main criteria for the selection of these

transistors is output voltage budgeting. The maximum

rDS(ON) allowed at highest junction temperature can be

expressed with the following equation:

, where

VINmin - minimum input voltage

VOUTmin - minimum output voltage allowed

IOUTmax - maximum output current

If a P-Channel MOSFET is used to switch the 5VSB output of

the ATX supply into the 5VDUAL output during sleep states,

then the selection criteria of this device is proper voltage

budgeting. The maximum rDS(ON), however, has to be

achieved with only 4.5V of gate-to-source voltage, so a logic

level MOSFET needs to be sele cted. If a PNP device is

chosen to perform this function, it has to have a low-

saturation voltage while providing the maximum sleep

current and have a current gain sufficiently high to be

saturated using the minimum drive current (typically 20mA).

ISL6504 Application Circuit

Figure 12 shows a typical application circuit for the

ISL6504/A. The circuit provides the 3.3VDUAL/3.3VSB

voltage, the ICH4 resume well 1.5VSB voltage, the 1.2VVID

voltage identification output, and the 5VDUAL

keyboard/mouse voltage from +3.3V, +5VSB, +5V, and

+12VDC ATX supply outputs. Q3 can also be a PNP

transistor, such as an MMBT2907AL. For additional, more

detailed information on the circuit, including a Bill-of-

Materials and circuit board description, see Application Note

AN1001. Also see Intersil Corporation’s web page

(www.intersil.com).

rDS ON()max VINmin VOUTmin

–

IOUTmax

---------------------------------------------------=

FIGURE 12. TYPICAL ISL6504/A APPLICATION DIAGRAM

1mF

220mF

330mF

GND

5VSB

ISL6504/A

+3.3VDUAL/3.3VSB

+5VDUAL

3V3DL

3V3DLSB

DLA

5VDLSB

FAULT

5VDL

2SD1802

FDV304P

HUF76113T3S

C4 U1

+5VSB

+5VIN

+12VIN

+3.3VIN

‘FAULT’

3V3

+1.5VSB

HUF76113T3S

1V5SB

10mF

1V2VID

C3 +

+1.2VVID

10mF

C5 +

VID_PG ‘VID PGOOD’

10k

VID_CT

0.1mF

ISL6504, ISL6504A

14 FN9062.2

April 13, 2004

ISL6504, ISL6504A

Small Outline Plastic Packages (SOIC)

NOTES:

1. Symbols are defined in the “MO Series Symbol List” in Section 2.2 of

Publication Number 95.

2. Dimensioning and tolerancing per ANSI Y14.5M-1982.

3. Dimension “D” does not include mold flash, protrusions or gate burrs.

Mold flash, protrusion and gate burrs shall not exceed 0.15mm (0.006

inch) per side.

4. Dimension “E” does not include interlead flash or protrusions. Interlead

flash and protrusions shall not exceed 0.25mm (0.010 inch) per side.

5. The chamfer on the body is optional. If it is not present, a visual index

feature must be located within the crosshatched area.

6. “L” is the length of terminal for soldering to a substrate.

7. “N” is the number of terminal positions.

8. Terminal numbers are shown for reference only.

9. The lead width “B”, as measured 0.36mm (0.014 inch) or greater above

the seating plane, shall not exceed a maximum value of 0.61mm (0.024

inch)

10. Controlling dimension: MILLIMETER. Converted inch dimensions are

not necessarily exact.

INDEX

AREA E

123

-B-

0.25(0.010) C AMBS

-A-

-C-

SEATING PLANE

0.10(0.004)

h x 45o

0.25(0.010) BM M

M16.3 (JEDEC MS-013-AA ISSUE C)

16 LEAD WIDE BODY SMALL OUTLINE PLASTIC PACKAGE

SYMBOL

INCHES MILLIMETERS

NOTESMIN MAX MIN MAX

A 0.0926 0.1043 2.35 2.65 -

A1 0.0040 0.0118 0.10 0.30 -

B 0.013 0.0200 0.33 0.51 9

C 0.0091 0.0125 0.23 0.32 -

D 0.3977 0.4133 10.10 10.50 3

E 0.2914 0.2992 7.40 7.60 4

e 0.050 BSC 1.27 BSC -

H 0.394 0.419 10.00 10.65 -

h 0.010 0.029 0.25 0.75 5

L 0.016 0.050 0.40 1.27 6

N16 167

α0o8o0o8o-

Rev. 0 12/93

15 FN9062.2

April 13, 2004

ISL6504, ISL6504A

Quad Flat No-Lead Plastic Package (QFN)

Micro Lead Frame Plastic Package (MLFP) L20.6x6

20 LEAD QUAD FLAT NO-LEAD PLASTIC PACKAGE

(COMPLIANT TO JEDEC MO-220VJJB ISSUE C)

SYMBOL

MILLIMETERS

NOTESMIN NOMINAL MAX

A 0.80 0.90 1.00 -

A1 - - 0.05 -

A2 - - 1.00 9

A3 0.20 REF 9

b 0.28 0.33 0.40 5, 8

D 6.00 BSC -

D1 5.75 BSC 9

D2 3.55 3.70 3.85 7, 8

E 6.00 BSC -

E1 5.75 BSC 9

E2 3.55 3.70 3.85 7, 8

e 0.80 BSC -

k0.25 - - -

L 0.35 0.60 0.75 8

L1 - - 0.15 10

N202

Nd 5 3

Ne 5 3

P- -0.609

θ--129

Rev. 1 10/02

NOTES:

1. Dimensioning and tolerancing conform to ASME Y14.5-1994.

2. N is the number of terminals.

3. Nd and Ne refer to the number of terminals on each D and E.

4. All dimensions are in millimeters. Angles are in degrees.

5. Dimension b applies to the metallized terminal and is measured

between 0.15mm and 0.30mm from the terminal tip.

6. The configuration of the pin #1 identifier is optional, but must be

located within the zone indicated. The pin #1 identifier may be

either a mold or mark feature.

7. Dimensions D2 and E2 are for the exposed pads which provide

improved electrical and thermal performance.

8. Nominal dimensions are provided to assist with PCB Land Pattern

Design efforts, see Intersil Technical Brief TB389.

9. Features and dimensions A2, A3, D1, E1, P & θ are present when

Anvil singulation method is used and not present for saw

singulation.

10. Depending on the method of lead termination at the edge of the

package, a maximum 0.15mm pull ba ck (L1) maybe present. L

minus L1 to be equal to or greater than 0.3mm.

All Intersil U.S. products are manufactured, assembled and tested utilizing ISO9000 quality systems.

Intersil Corporation’s quality certifications can be viewed at www.intersil.com/design/quality

Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without

notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and

reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result

from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries.

For information regarding Intersil Corporation and its products, see www.intersil.com

FN9062.2

April 13, 2004

ISL6504, ISL6504A

Small Outline Plastic Packages (SOIC)

NOTES:

1. Symbols are defined in the “MO Series Symbol List” in Section

2.2 of Publication Number 95.

2. Dimensioning and tolerancing per ANSI Y14.5M-1982.

3. Dimension “D” does not include mold flash, protrusions or gate

burrs. Mold flash, protrusion and gate burrs shall not exceed

0.15mm (0.006 inch) per side.

4. Dimension “E” does not include interlead flash or protrusions. In-

terlead flash and protrusions shall not exceed 0.25mm (0.010

inch) per side.

5. The chamfer on the body is optional. If it is not present, a visual

index feature must be located within the crosshatched area.

6. “L” is the length of terminal for soldering to a substrate.

7. “N” is the number of terminal positions.

8. Terminal numbers are shown for reference only.

9. The lead width “B”, as measured 0.36mm (0.014 inch) or greater

above the seating plane, shall not exceed a maximum value of

0.61mm (0.024 inch)

10. Controlling dimension: MILLIMETER. Converted inch dimen-

sions are not necessarily exact.

INDEX

AREA

123

-B-

0.25(0.010) C A

MBS

-A-

-C-

SEATING PLANE

0.10(0.004)

h x 45o

0.25(0.010) B

M16.15 (JEDEC MS-012-AC ISSUE C)

16 LEAD NARROW BODY SMALL OUTLINE PLASTIC PACKAGE

SYMBOL

INCHES MILLIMETERS

NOTESMIN MAX MIN MAX

A0.053 0.069 1.35 1.75 -

A1 0.004 0.010 0.10 0.25 -

B0.014 0.019 0.35 0.49 9

C0.007 0.010 0.19 0.25 -

D0.386 0.394 9.80 10.00 3

E0.150 0.157 3.80 4.00 4

e 0.050 BSC 1.27 BSC -

H0.228 0.244 5.80 6.20 -

h0.010 0.020 0.25 0.50 5

L0.016 0.050 0.40 1.27 6

N16 167

α0o8o0o8o-

Rev. 1 02/02