Rainbow Electronics MAX8760 User Manual

General Description

The MAX8760 is a dual-phase, Quick-PWM™, step­down controller for 6-bit VID AMD Mobile Turion™ 64
CPU core supplies. Dual-phase operation reduces input
ripple current requirements and output voltage ripple
while easing component selection and layout difficulties.
The quick-PWM control scheme provides instantaneous
response to fast-load current steps. The MAX8760
includes active voltage positioning with adjustable gain
and offset, reducing power dissipation and bulk output
capacitance requirements.

The MAX8760 is intended for two different notebook CPU
core applications: stepping down the battery directly or
stepping down the 5V system supply to create the core
voltage. The single-stage conversion method allows this
device to directly step down high-voltage batteries for the
highest possible efficiency. Alternatively, two-stage con­version (stepping down the 5V system supply instead of
the battery) at a higher switching frequency provides the
minimum possible physical size.

The MAX8760 complies with AMD’s desktop and mobile
CPU specifications. The switching regulator features soft­start and power-up sequencing, and soft-shutdown. The
MAX8760 also features independent four-level logic inputs
for setting the suspend voltage (S0, S1).

The MAX8760 includes output undervoltage protection,
thermal protection, and voltage regulator power-OK
(VROK) output. When any of these protection features
detect a fault, the controller shuts down.

The MAX8760 is available in a low-profile, 40-pin 6mm x
6mm thin QFN package. For other CPU platforms, refer to
the pin-to-pin compatible MAX1544, MAX1519/MAX1545,
and MAX1532/MAX1546/MAX1547 data sheets.

Applications

6-Bit VID AMD Mobile Turion 64 CPU

Multiphase CPU Core Supply

Voltage-Positioned Step-Down Converters

Servers/Desktop Computers

Features

♦ Dual-Phase, Quick-PWM Controller

♦ ±0.75% V

OUT

Accuracy Over Line, Load, and

Temperature (1.3V)

♦ Active Voltage Positioning with Adjustable Gain

and Offset

♦ 6-Bit On-Board DAC: 0.375V to 1.55V Output

Adjust Range

♦ Selectable 100kHz/200kHz/300kHz/550kHz

Switching Frequency

♦ 4V to 28V Battery Input Voltage Range

♦ Adjustable Slew-Rate Control

♦ Drives Large Synchronous Rectifier MOSFETs

♦ Undervoltage and Thermal-Fault Protection

♦ Power Sequencing and Timing

♦ Selectable Suspend Voltage

♦ Soft-Start and Soft-Shutdown

♦ Selectable Single- or Dual-Phase Pulse Skipping

D4
D5

OAIN+
OAIN-

GNDS

CCV
GND

FB
CCI

DHS

LXS

BSTS

CMP
CMN

CSN

12345678910

30 29 28 27 26 25 24

23 22 21

CSP

DLS

PGND

31

32

33

34

35

36

37

38

39

40

20

19

18

17

16

15

14

13

12

11

S1

OFS

REF

ILIM

V

CC

S0

SUS

TON

TIME

DLM

DHM

LXM

BSTM

VROKD0D1D2D3

V

DD

THIN QFN

MAX8760

TOP VIEW

V+

SKIP

SHDN

Pin Configuration

Ordering Information

PART

PIN-PACKAGE

MAX8760ETL

40 Thin QFN 6mm x 6mm

MAX8760ETL+

40 Thin QFN 6mm x 6mm

MAX8760

Dual-Phase, Quick-PWM Controller for AMD

Mobile Turion 64 CPU Core Power Supplies

________________________________________________________________ Maxim Integrated Products 1

19-3721; Rev 0; 5/05

For pricing delivery, and ordering information please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

Quick-PWM is a trademark of Maxim Integrated Products, Inc.

Turion is a trademark of AMD.

+Denotes lead-free package.

TEMP RANGE

-40°C to +100°C

-40°C to +100°C

MAX8760

Dual-Phase, Quick-PWM Controller for AMD
Mobile Turion 64 CPU Core Power Supplies

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.

V+ to GND ..............................................................-0.3V to +30V

V

CC

to GND..............................................................-0.3V to +6V

V

DD

to PGND............................................................-0.3V to +6V

SKIP, SUS, D0–D5 to GND.......................................-0.3V to +6V

ILIM, FB, OFS, CCV, CCI, REF, OAIN+,

OAIN- to GND.........................................-0.3V to (V

CC

+ 0.3V)

CMP, CSP, CMN, CSN, GNDS to GND ......-0.3V to (V

CC

+ 0.3V)

TON, TIME, VROK, S0–S1 to GND..............-0.3V to (V

CC

+ 0.3V)

SHDN to GND (Note 1)...........................................-0.3V to +18V

DLM, DLS to PGND....................................-0.3V to (V

DD

+ 0.3V)

BSTM, BSTS to GND ..............................................-0.3V to +36V

DHM to LXM ...........................................-0.3V to (V

BSTM

+ 0.3V)

LXM to BSTM............................................................-6V to +0.3V

DHS to LXS..............................................-0.3V to (V

BSTS

+ 0.3V)

LXS to BSTS .............................................................-6V to +0.3V

GND to PGND .......................................................-0.3V to +0.3V

REF Short-Circuit Duration .........................................Continuous

Continuous Power Dissipation (T

A

= +70°C)

40-Pin 6mm

✕ 6mm Thin QFN

(derate 23.2mW/°C above +70°C)...............................1.860W

Operating Temperature Range .........................-40°C to +100°C

Junction Temperature......................................................+150°C

Storage Temperature Range .............................-65°C to +150°C

Lead Temperature (soldering, 10s) .................................+300°C

ELECTRICAL CHARACTERISTICS

(Circuit of Figure 1, V+ = 15V, VCC= VDD= V

SHDN

= V

SKIP

= VS0= VS1= 5V, VFB= V

CMP

= V

CMN

= V

CSP

= V

CSN

= 1.3V, OFS =

SUS = GNDS = D0–D5 = GND, T

A

= 0°C to +85°C, unless otherwise specified. Typical values are at TA= +25°C.)

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

PWM CONTROLLER

Battery voltage, V+ 4 28

Input Voltage Range

V

CC

, V

DD

4.5 5.5

V

DAC codes ≥ 1V -10

DC Output Voltage Accuracy
(Note 2)

V+ = 4.5V to 28V,
includes load
regulation error

DAC codes from

0.375V to 1V

-15

mV

Line Regulation Error VCC = 4.5V to 5.5V, V+ = 4.5V to 28V 5 mV

FB, GNDS -2 +2

Input Bias Current

I

OFS

OFS

µA

OFS Input Range 02V

∆V

OUT

/∆V

OFS;

∆V

OFS

= V

OFS, VOFS

= 0 to 1V

OFS Gain A

OFS

∆V

OUT

/∆V

OFS;

∆V

OFS

= V

OFS

- V

REF, VOFS

= 1V to 2V

V/V

GNDS Input Range -20

mV

GNDS Gain A

GNDS

∆V

OUT

/∆V

GNDS

V/V

1000kHz nominal, R

TIME

= 15kΩ

500kHz nominal, R

TIME

= 30kΩ

250kHz nominal, R

TIME

= 60kΩ

TIME Frequency Accuracy f

TIME

Startup and shutdown, R

TIME

= 30kΩ

kHz

Note 1: SHDN may be forced to 12V for the purpose of debugging prototype boards using the no-fault test mode, which disables

fault protection and overlapping operation.

+10

+15

IFB, I

GNDS

-0.1 +0.1

-0.129 -0.125 -0.117

-0.129 -0.125 -0.117

0.97 0.99 1.01

900 1000 1100

460 500 540

225 250 275

125

+200

MAX8760

Dual-Phase, Quick-PWM Controller for AMD

Mobile Turion 64 CPU Core Power Supplies

_______________________________________________________________________________________ 3

ELECTRICAL CHARACTERISTICS (continued)

(Circuit of Figure 1, V+ = 15V, VCC= VDD= V

SHDN

= V

SKIP

= VS0= VS1= 5V, VFB= V

CMP

= V

CMN

= V

CSP

= V

CSN

= 1.3V, OFS =

SUS = GNDS = D0–D5 = GND, T

A

= 0°C to +85°C, unless otherwise specified. Typical values are at TA= +25°C.)

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

TON = GND
(550kHz)

TON = REF
(300kHz)

TON = open
(200kHz)

On-Time (Note 3) t

ON

V+ = 12V,
V

FB

= V

CCI

= 1.2V

TON = V

CC

(100kHz)

ns

TON = GND

Minimum Off-Time (Note 3)

)

TON = VCC, open, or REF

ns

BIAS AND REFERENCE

Quiescent Supply Current (VCC)I

CC

Measured at VCC, FB forced above the

mA

Quiescent Supply Current (VDD)I

DD

Measured at VDD, FB forced above the
regulation point

<1 5 µA

Quiescent Battery Supply Current
(V+)

I

V+

Measured at V+ 25 40 µA

Shutdown Supply Current (VCC) Measured at VCC, SHDN = GND 4 10 µA

Shutdown Supply Current (VDD) Measured at VDD, SHDN = GND <1 5 µA

Shutdown Battery Supply Current
(V+)

Measured at V+, SHDN = GND,
V

CC

= VDD = 0V or 5V

<1 5 µA

Reference Voltage V

REF

V

CC

= 4.5V to 5.5V, I

REF

= 0

V

Reference Load Regulation ∆V

REFIREF

= -10µA to 100µA -10

mV

FAULT PROTECTION

Output Overvoltage Protection
Threshold

V

OVP

V

Output Overvoltage Propagation
Delay

t

OVP

FB forced 2% above trip threshold 10 µs

Output Undervoltage Protection
Threshold

V

UVP

Measured at FB with respect to unloaded
output voltage

67 70 73 %

Output Undervoltage Propagation
Delay

t

UVP

FB forced 2% below trip threshold 10 µs

Lower threshold
(undervoltage)

-12 -10 -8

VROK Threshold

Measured at FB
with respect to
unloaded output
voltage

Upper threshold
(overvoltage)
SKIP = V

CC

+8

%

t

OFF(MIN

regulation point, OAIN- = FB, V

= 1.3V

OAI N +

155 180 205

320 355 390

475 525 575

920 1000 1140

1.990 2.000 2.010

300 375

400 480

1.70 3.20

2.00

+10 +12

+10

MAX8760

Dual-Phase, Quick-PWM Controller for AMD
Mobile Turion 64 CPU Core Power Supplies

4 _______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS (continued)

(Circuit of Figure 1, V+ = 15V, VCC= VDD= V

SHDN

= V

SKIP

= VS0= VS1= 5V, VFB= V

CMP

= V

CMN

= V

CSP

= V

CSN

= 1.3V, OFS =

SUS = GNDS = D0–D5 = GND, T

A

= 0°C to +85°C, unless otherwise specified. Typical values are at TA= +25°C.)

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

Output Undervoltage Fault and
VROK Transition Blanking Time

t

BLANK

Measured from the time when FB reaches
the voltage set by the DAC code; clock
speed set by R

TIME

(Note 4)

24 Clks

VROK Startup Delay

Measured from the time when FB first
reaches the voltage set by the DAC code
after startup

357ms

VROK Delay t

VROK

FB forced 2% outside the VROK trip
threshold

10 µs

VROK Output Low Voltage I

SINK

= 3mA 0.4 V

VROK Leakage Current High state, VROK forced to 5.5V 1 µA

VCC Undervoltage Lockout
Threshold

)

Rising edge, hysteresis = 90mV, PWM
disabled below this level

4.0

4.4 V

Thermal-Shutdown Threshold T

SHDN

Hysteresis = 10°C

°C

CURRENT LIMIT AND BALANCE

Current-Limit Threshold Voltage
(Positive, Default)

V

LIMIT

CMP - CMN, CSP - CSN; ILIM = V

CC

28 30 32 mV

V

ILIM

= 0.2V 8 10 12

Current-Limit Threshold Voltage
(Positive, Adjustable)

V

LIMIT

V

ILIM

= 1.5V 73 75 77

mV

Current-Limit Threshold Voltage
(Negative)

)

CMP - CMN, CSP - CSN; ILIM = VCC,
SKIP = V

CC

-41 -36 -31 mV

Current-Limit Threshold Voltage
(Zero Crossing)

V

ZERO

CMP - CMN, CSP - CSN; SKIP = GND 1.5 mV

CMP, CMN, CSP, CSN Input
Ranges

02V

CMP, CMN, CSP, CSN Input
Current

V

CSP

= V

CSN

= 0 to 5V -2 +2 µA

Secondary Driver-Disable
Threshold

V

CSP

3

VCC -

0.4

V

ILIM Input Current I

ILIM

V

ILIM

= 0 to 5V 0.1

nA

Current-Limit Default Switchover
Threshold

V

ILIM

3

VCC -

0.4

V

Current-Balance Offset

)

(V

CMP

- V

CMN

) - (V

CSP

- V

CSN

); I

CCI

= 0,

-20mV < (V

CMP

- V

CMN

) < 20mV,

1.0V < V

CCI

< 2.0V

-2 +2 mV

V

UVLO(VCC

4.25

+160

CMP - CMN, CSP - CSN

V

LIMIT(NEG

V

OS(IBAL

VCC - 1

VCC - 1

200

MAX8760

Dual-Phase, Quick-PWM Controller for AMD

Mobile Turion 64 CPU Core Power Supplies

_______________________________________________________________________________________ 5

ELECTRICAL CHARACTERISTICS (continued)

(Circuit of Figure 1, V+ = 15V, VCC= VDD= V

SHDN

= V

SKIP

= VS0= VS1= 5V, VFB= V

CMP

= V

CMN

= V

CSP

= V

CSN

= 1.3V, OFS =

SUS = GNDS = D0–D5 = GND, T

A

= 0°C to +85°C, unless otherwise specified. Typical values are at TA= +25°C.)

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

Current-Balance
Transconductance

)

µS

GATE DRIVERS

DH_ Gate-Driver On-Resistance R

ON(DH)

BST_ - LX_ forced to 5V 1.0 4.5 Ω

High state (pullup) 1.0 4.5

DL_ Gate-Driver On-Resistance R

ON(DL)

Low start (pulldown) 0.4 2

Ω

DH_ Gate-Driver Source/Sink
Current

I

DH

DH_ forced to 2.5V,
BST_ - LX_ forced to 5V

1.6 A

DL_ Gate-Driver Sink Current

)

DL_ forced to 5V 4 A

DL_ Gate-Driver Source Current

)

DL_ forced to 2.5V 1.6 A

DL_ rising 35

Dead Time t

DEAD

DH_ rising 26

ns

VOLTAGE-POSITIONING AMPLIFIER

Input Offset Voltage V

OS

-1 +1 mV

Input Bias Current I

BIAS

OAIN+, OAIN- 0.1

nA

Op Amp Disable Threshold V

OAIN-

3

VCC -

0.4

V

Common-Mode Input Voltage
Range

V

CM

Guaranteed by CMRR test 0 2.5 V

Common-Mode Rejection Ratio CMRR V

OAIN+

= V

OAIN-

= 0 to 2.5V 70

dB

Power-Supply Rejection Ratio PSRR VCC = 4.5V to 5.5V 75

dB

Large-Signal Voltage Gain A

OA

RL = 1kΩ to VCC/2 80

dB

VCC - V

FBH

77

Output Voltage Swing

|V

OAIN+

- V

OAIN-

| ≥ 10mV,

R

L

= 1kΩ to VCC/2

V

FBL

47

mV

Input Capacitance 11 pF

Gain-Bandwidth Product 3

MHz

Slew Rate 0.3 V/µs

Capacitive-Load Stability No sustained oscillations

pF

LOGIC AND I/O

SHDN Input High Voltage V

IH

0.8 V

SHDN Input Low Voltage V

IL

0.4 V

SHDN No-Fault Threshold V

SHDN

To enable no-fault mode 12 15 V

High 2.7
REF 1.2 2.3Three-Level Input Logic Levels SUS, SKIP

Low 0.8

V

Logic Input Current SHDN, SKIP, SUS -1 +1 µA

D0–D5 Logic Input High Voltage

1.6 V

G

m(IBAL

I

DL(SINK

I

DL(SOURCE

400

VCC - 1

115

100

112

400

200

300

200

MAX8760

Dual-Phase, Quick-PWM Controller for AMD
Mobile Turion 64 CPU Core Power Supplies

6 _______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS (continued)

(Circuit of Figure 1, V+ = 15V, VCC= VDD= V

SHDN

= V

SKIP

= VS0= VS1= 5V, VFB= V

CMP

= V

CMN

= V

CSP

= V

CSN

= 1.3V, OFS =

SUS = GNDS = D0–D5 = GND, T

A

= 0°C to +85°C, unless otherwise specified. Typical values are at TA= +25°C.)

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

D0–D5 Logic Input Low Voltage 0.8 V

D0–D5 Input Current D0–D5 -2 +2 µA

High

V

CC

-

0.4

Open

REF

Four-Level Input Logic Levels TON, S0 and S1

Low 0.4

V

Four-Level Input Current TON, S0 and S1 forced to GND or V

CC

-3 +3 µA

ELECTRICAL CHARACTERISTICS

(Circuit of Figure 1, V+ = 15V, VCC= VDD= V

SHDN

= V

SKIP

= VS0= VS1= 5V, VFB= V

CMP

= V

CMN

= V

CSP

= V

CSN

= 1.3V, OFS =

SUS = GNDS = D0–D5 = GND, T

A

= -40°C to +100°C, unless otherwise specified.) (Note 5)

PARAMETER

SYMBOL

CONDITIONS

MIN

MAX

UNITS

PWM CONTROLLER

Battery voltage, V+ 4 28

Input Voltage Range

V

CC

, V

DD

4.5 5.5

V

DAC codes ≥ 1V -13

DC Output Voltage Accuracy
(Note 2)

V+ = 4.5V to 28V,
includes load
regulation error

DAC codes from

0.375V to 1V

-20

mV

OFS Input Range 02V

∆V

OUT

/∆V

OFS;

∆V

OFS

= V

OFS, VOFS

= 0 to 1V

OFS GAIN A

OFS

∆V

OUT

/∆V

OFS;

∆V

OFS

= V

OFS

- V

REF, VOFS

= 1V to 2V

V/V

GNDS Gain A

GNDS

∆V

OUT

/∆V

GNDS

V/V

1000kHz nominal, R

TIME

= 15kΩ

500kHz nominal, R

TIME

= 30kΩ

TIME Frequency Accuracy f

TIME

250kHz nominal, R

TIME

= 60kΩ

kHz

TON = GND
(550kHz)

TON = REF
(300kHz)

TON = open
(200kHz)

On-Time (Note 3) t

ON

V+ = 12V,
V

FB

= V

CCI

= 1.2V

TON = V

CC

(100kHz)

ns

TON = GND

Minimum Off-Time (Note 3)

)

TON = VCC, open, or REF

ns

3.15 3.85

1.65 2.35

t

OFF(MIN

-0.131 -0.115

-0.131 -0.115

0.94 1.01

880 1120

450 550

220 280

150 210

315 395

470 580

910 1150

+13

+20

380

490

MAX8760

Dual-Phase, Quick-PWM Controller for AMD

Mobile Turion 64 CPU Core Power Supplies

_______________________________________________________________________________________ 7

ELECTRICAL CHARACTERISTICS (continued)

(Circuit of Figure 1, V+ = 15V, VCC= VDD= V

SHDN

= V

SKIP

= VS0= VS1= 5V, VFB= V

CMP

= V

CMN

= V

CSP

= V

CSN

= 1.3V, OFS =

SUS = GNDS = D0–D5 = GND, T

A

= -40°C to +100°C, unless otherwise specified.) (Note 5)

PARAMETER

SYMBOL

CONDITIONS

MIN

MAX

UNITS

BIAS AND REFERENCE

Quiescent Supply Current (VCC)

I

CC

Measured at VCC, FB forced above the

3.2 mA

Quiescent Supply Current (VDD)

I

DD

Measured at VDD, FB forced above the
regulation point

20 µA

Quiescent Battery Supply Current
(V+)

I

V+

Measured at V+ 50 µA

Shutdown Supply Current (VCC)

Measured at VCC, SHDN = GND 20 µA

Shutdown Supply Current (VDD)

Measured at VDD, SHDN = GND 20 µA

Shutdown Battery Supply Current
(V+)

Measured at V+, SHDN = GND,
V

CC

= VDD = 0V or 5V

20 µA

Reference Voltage V

REF

VCC = 4.5V to 5.5V, I

REF

= 0

V

FAULT PROTECTION

Output Undervoltage Protection
Threshold

V

UVP

Measured at FB with respect to unloaded
output voltage

67 73 %

Lower threshold
(undervoltage)

-13 -7

VROK Threshold

Measured at FB
with respect to
unloaded output
voltage

Upper threshold
(overvoltage),
SKIP = V

CC

+7

%

VROK Startup Delay

Measured from the time when FB first
reaches the voltage set by the DAC code
after startup

3ms

VCC Undervoltage Lockout
Threshold

)

Rising edge, hysteresis = 90mV, PWM
disabled below this level

V

CURRENT LIMIT AND BALANCE

Current-Limit Threshold Voltage
(Positive, Default)

V

LIMIT

CMP - CMN, CSP - CSN; ILIM = V

CC

27 33 mV

V

ILIM

= 0.2V 7 13

Current-Limit Threshold Voltage
(Positive, Adjustable)

V

LIMIT

CMP - CMN,
CSP - CSN

V

ILIM

= 1.5V 72 78

mV

Current-Limit Threshold Voltage
(Negative)

)

CMP - CMN, CSP - CSN; ILIM = VCC,
SKIP = V

CC

-30 -42 mV

Current-Balance Offset

)

(V

CMP

- V

CMN

) - (V

CSP

- V

CSN

); I

CCI

= 0,

-20mV < (V

CMP

- V

CMN

) < 20mV,

1.0V < V

CCI

< 2.0V

-3 +3 mV

GATE DRIVERS

DH_ Gate-Driver On-Resistance

)

BST_ - LX_ forced to 5V 4.5 Ω

regulation point, OAIN- = FB, V

V

UVLO(VCC

V

LIMIT(NEG

V

OS(IBAL

R

ON(DH

OAI N +

= 1.3V

1.985 2.015

+13

3.90 4.45

MAX8760

Dual-Phase, Quick-PWM Controller for AMD
Mobile Turion 64 CPU Core Power Supplies

8 _______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS (continued)

(Circuit of Figure 1, V+ = 15V, VCC= VDD= V

SHDN

= V

SKIP

= VS0= VS1= 5V, VFB= V

CMP

= V

CMN

= V

CSP

= V

CSN

= 1.3V, OFS =

SUS = GNDS = D0–D5 = GND, T

A

= -40°C to +100°C, unless otherwise specified.) (Note 5)

PARAMETER

SYMBOL

CONDITIONS

MIN

MAX

UNITS

High state (pullup) 4.5

DL_ Gate-Driver On-Resistance R

ON(DL)

Low start (pulldown) 2

Ω

VOLTAGE-POSITIONING AMPLIFIER

Input Offset Voltage V

OS

mV

Common-Mode Input Voltage
Range

V

CM

Guaranteed by CMRR test 0 2.5 V

VCC - V

FBH

300

Output Voltage Swing

|V

OAIN+

- V

OAIN-

| ≥ 10mV,

R

L

= 1kΩ to VCC/2

V

FBL

200

mV

LOGIC AND I/O

SHDN Input High Voltage V

IH

0.8 V

SHDN Input Low Voltage V

IL

0.4 V

High 2.7
REF 1.2 2.3Tri-Level Input Logic Levels SUS, SKIP

Low 0.8

V

D0–D5 Logic Input High Voltage

1.6 V

D0–D5 Logic Input Low Voltage 0.8 V

High

V

CC

-

0.4

Open

REF

Four-Level Input Logic Levels TON, S0 and S1

Low 0.4

V

Note 2: DC output accuracy specifications refer to the trip level of the error amplifier. When pulse skipping, the output slightly rises

(<0.5%) when transitioning from continuous conduction to no load.

Note 3: On-time and minimum off-time specifications are measured from 50% to 50% at the DHM and DHS pins, with LX_ forced to

GND, BST_ forced to 5V, and a 500pF capacitor from DH_ to LX_ to simulate external MOSFET gate capacitance. Actual in­circuit times may be different due to MOSFET switching speeds.

Note 4: The output fault-blanking time is measured from the time when FB reaches the regulation voltage set by the DAC code.

During normal operation (SUS = GND), the regulation voltage is set by the VID DAC inputs (D0–D5). During suspend mode
(SUS = REF or high), the regulation voltage is set by the suspend DAC inputs (S0 and S1).

Note 5: Specifications to T

A

= -40°C and +100°C are guaranteed by design and are not production tested.

-2.0 +2.0

3.15 3.85

1.65 2.35

MAX8760

Dual-Phase, Quick-PWM Controller for AMD

Mobile Turion 64 CPU Core Power Supplies

_______________________________________________________________________________________ 9

OUTPUT VOLTAGE vs. LOAD CURRENT

(V

OUT

= 1.30V)

MAX8760 toc01

LOAD CURRENT (A)

OUTPUT VOLTAGE (V)

302010

1.20

1.22

1.24

1.26

1.28

1.30

1.32

1.18
040

VIN = 12V
SKIP = V

CC

OR REF

EFFICIENCY vs. LOAD CURRENT

(V

OUT

= 1.30V)

MAX8760 toc02

LOAD CURRENT (A)

EFFICIENCY (%)

101

60

70

80

90

100

50

0.01 100

VIN = 7V

VIN = 12V

VIN = 20V

SKIP = REF
SKIP = V

CC

OUTPUT VOLTAGE vs. LOAD CURRENT

(V

OUT

= 1.00V)

MAX8760 toc03

LOAD CURRENT (A)

OUTPUT VOLTAGE (V)

302010

0.90

0.92

0.94

0.96

0.98

1.00

1.02

1.04

0.88
040

VIN = 12V
SKIP = V

CC

OR REF

EFFICIENCY vs. LOAD CURRENT

(V

OUT

= 1.00V)

MAX8760 toc04

LOAD CURRENT (A)

EFFICIENCY (%)

101

60

70

80

90

100

50

0.01 100

VIN = 7V

VIN = 12V

VIN = 20V

SKIP = REF
SKIP = V

CC

OUTPUT VOLTAGE vs. LOAD CURRENT

(V

OUT

= 0.80V)

MAX8760 toc05

LOAD CURRENT (A)

OUTPUT VOLTAGE (V)

15105

0.76

0.78

0.80

0.82

0.84

0.74
020

VIN = 12V
SKIP = REF or GND

EFFICIENCY vs. LOAD CURRENT

(V

OUT

= 0.80V)

MAX8760 toc06

LOAD CURRENT (A)

EFFICIENCY (%)

101

60

70

80

90

100

50

0.01 100

VIN = 7V

VIN = 20V

SKIP = REF
SKIP = GND

SWITCHING FREQUENCY

vs. LOAD CURRENT

MAX8760 toc07

LOAD CURRENT (A)

SWITCHING FREQUENCY (kHz)

3010 20

100

200

300

400

0

040

V

OUT

= 1V (NO LOAD)

SKIP MODE (SKIP = REF)

FORCED-PWM (SKIP = VCC)

NO-LOAD SUPPLY CURRENT

vs. INPUT VOLTAGE (FORCED-PWM MODE)

MAX8760 toc08

INPUT VOLTAGE (V)

SUPPLY CURRENT (mA)

20 255 1510

30

60

90

120

150

0

030

I

IN

SKIP = V

CC

ICC + I

DD

NO-LOAD SUPPLY CURRENT

vs. INPUT VOLTAGE (PULSE SKIPPING)

MAX8760 toc09

INPUT VOLTAGE (V)

SUPPLY CURRENT (mA)

20 255 1510

0.5

1.0

1.5

2.0

2.5

3.0

0

030

IIN

SKIP = REF

ICC + I

DD

Typical Operating Characteristics

(Circuit of Figure 1, VIN= 12V, VCC= VDD= 5V, SHDN = SKIP = VCC, D0–D5 set for 1.5V (SUS = GND), S0 and S1 set for 1V
(SUS = V

CC

), OFS = GND, TA= +25°C, unless otherwise specified.)

MAX8760

Dual-Phase, Quick-PWM Controller for AMD
Mobile Turion 64 CPU Core Power Supplies

10 ______________________________________________________________________________________

OUTPUT OFFSET VOLTAGE

vs. OFS VOLTAGE

MAX8760 toc10

OFS VOLTAGE (V)

OUTPUT OFFSET VOLTAGE (mV)

1.50.5 1.0

-100

-50

0

50

100

150

-150
0 2.0

UNDEFINED
REGION

REFERENCE VOLTAGE

DISTRIBUTION

MAX8760 toc11

REFERENCE VOLTAGE (V)

SAMPLE PERCENTAGE (%)

2.0051.995

2.000

10

20

30

40

50

0

1.990 2.010

SAMPLE SIZE = 100

CURRENT-BALANCE OFFSET

VOLTAGE DISTRIBUTION

MAX8760 toc12

OFFSET VOLTAGE (mV)

SAMPLE PERCENTAGE (%)

1.25-1.25

0

10

20

30

40

50

0

-2.50 2.50

SAMPLE SIZE = 100

CURRENT-LIMIT THRESHOLD

DISTRIBUTION

MAX8760 toc13

CURRENT LIMIT (mV)

SAMPLE PERCENTAGE (%)

10.59.5

10.0

10

20

30

40

50

0

9.0 11.0

V

ILIM

= 0.20V

SAMPLE SIZE = 100

60

-40

0.1 10 100 1k1 10k

VOLTAGE-POSITIONING AMPLIFIER

GAIN AND PHASE vs. FREQUENCY

-20

-10

0

-30

MAX8760 toc14

FREQUENCY (Hz)

GAIN (dB)

PHASE (DEGREES)

10

20

30

40

50

180

-180

-108

-72

-36

-144

0

36

72

108

144

GAIN

PHASE

Typical Operating Characteristics (continued)

(Circuit of Figure 1, VIN= 12V, VCC= VDD= 5V, SHDN = SKIP = VCC, D0–D5 set for 1.5V (SUS = GND), S0 and S1 set for 1V
(SUS = V

CC

), OFS = GND, TA= +25°C, unless otherwise specified.)

VPS AMPLIFIER OFFSET VOLTAGE

vs. COMMON-MODE VOLTAGE

MAX8760 toc15

COMMON-MODE VOLTAGE (V)

34

1 205

OFFSET VOLTAGE (µV)

20

40

60

80

100

120

140

160

180

0

VPS AMPLIFIER

DISABLED

INDUCTOR CURRENT DIFFERENCE

vs. LOAD CURRENT

MAX8760 toc16

LOAD CURRENT (A)

30 40

10

20

050

I

L(CS)

- I

L(CM)

(A)

0.2

0.4

0.6

0.8

1.0

0

R

SENSE

= 1mΩ

SKIP = REF

SKIP = V

CC

MAX8760

Dual-Phase, Quick-PWM Controller for AMD

Mobile Turion 64 CPU Core Power Supplies

______________________________________________________________________________________ 11

POWER-UP SEQUENCE

MAX8760 toc17

0

3.3V

0

0

0

1.46V

0

B

C

D

E

A

2ms/div

A. SHDN, 5V/div
B. VROK, 5V/div
C. 1.5V OUTPUT, 1V/div

R

LOAD

= 75mΩ

D. I

L1

, 10A/div

E. I

L2

, 10A/div

SOFT-SHUTDOWN WAVEFORMS

MAX8760 toc19

3.3V

10A

10A

1.46V

B

C

D

A

200µs/div

A. SHDN, 5V/div
B. 1.5V OUTPUT, 500mV/div
C. I

L1

, 10A/div

D. I

L2

, 10A/div

R

LOAD

= 75mΩ

1.30V LOAD TRANSIENT
(10A TO 30A LOAD)

MAX8760 toc20

15A

1.48A

1.44V

5A

5A

15A

B

C

A

20µs/div

A. I

L1

, 10A/div

B. I

L2

, 10A/div

C. OUTPUT VOLTAGE, 20mV/div

OFFSET TRANSITION

MAX8760 toc21

0.2V

5A

5A

0

1.5V

B

C

D

A

20µs/div

A. V

OFS

= 0 TO 200mV, 0.2V/div

B. V

OUT

= 1.500V TO 1.475V, 20mV/div

C. I

L1

, 10A/div

D. I

L2

, 10A/div

10A LOAD

Typical Operating Characteristics (continued)

(Circuit of Figure 1, VIN= 12V, VCC= VDD= 5V, SHDN = SKIP = VCC, D0–D5 set for 1.5V (SUS = GND), S0 and S1 set for 1V
(SUS = V

CC

), OFS = GND, TA= +25°C, unless otherwise specified.)

SOFT-START

MAX8760 toc18

3.3V

0

0

0

0

B

C

D

A

200µs/div

A. SHDN, 5V/div
B. 1.5V OUTPUT, 500mV/div
C. I

L1

, 10A/div

D. I

L2

, 10A/div

R

LOAD

= 75mΩ

MAX8760

Dual-Phase, Quick-PWM Controller for AMD
Mobile Turion 64 CPU Core Power Supplies

12 ______________________________________________________________________________________

Typical Operating Characteristics (continued)

(Circuit of Figure 1, VIN= 12V, VCC= VDD= 5V, SHDN = SKIP = VCC, D0–D5 set for 1.5V (SUS = GND), S0 and S1 set for 1V
(SUS = V

CC

), OFS = GND, TA= +25°C, unless otherwise specified.)

SUSPEND TRANSITION

(DUAL-PHASE PWM OPERATION)

MAX8760 toc22

3.3V

2.5A

2.5A

0

1.5V

1.0V

B

C

D

A

40µs/div

A. SUS, 5V/div
B. V

OUT

= 1.5V TO 1.0V, 0.5V/div

C. I

L1

, 10A/div

D. I

L2

, 10A/div

5A LOAD, SKIP = V

CC

, R

TIME

= 64.9kΩ

SUSPEND TRANSITION

(SINGLE-PHASE SKIP OPERATION)

MAX8760 toc23

3.3V

0

10A

0

10A

0

1.5V

1.0V

B

C

D

A

100µs/div

A. SUS, 5V/div
B. V

OUT

= 1.5V TO 1.0V, 0.5V/div

C. I

L1

, 10A/div

D. I

L2

, 10A/div

5A LOAD, C

OUT

= (4) 680µF, SKIP = SUS, R

TIME

= 64.9kΩ

SINGLE-PHASE SKIP TO DUAL-PHASE

PWM TRANSITION

MAX8760 toc24

5V

0

0

1.5V

B

C

D

A

20µs/div

A. SKIP = V

CC

TO GND, 5V/div
B. 1.5V OUTPUT, 50mV/div
C. I

L1

, 10A/div

D. I

L2

, 10A/div

2A LOAD

DUAL-PHASE SKIP TO DUAL-PHASE

PWM TRANSITION

MAX8760 toc25

5V
2V

0

0

1.5V

B

C

D

A

20µs/div

A. SKIP = V

CC

TO REF, 5V/div
B. 1.5V OUTPUT, 50mV/div
C. I

L1

, 10A/div

D. I

L2

, 10A/div

2A LOAD