Analog Devices ADP3163 Datasheet

5-Bit Programmable 2-/3-Phase

a

FEATURES
ADOPT™ Optimal Positioning Technology for Superior

Load Transient Response and Fewest Output
Capacitors

Complies with VRM 9.0 and Intel VR Down Guideline

with Lowest System Cost

Digitally Selectable 2- or 3-Phase Operation

at up to 500 kHz per Phase

Quad Logic-level PWM Outputs for Interface to

External High-Power Drivers
Active Current Balancing between All Output Phases
Accurate Multiple VRM Module Current Sharing
5-Bit Digitally Programmable 1.1 V to 1.85 V Output
Total Output Accuracy 0.8% Over Temperature
Current-Mode Operation
Short Circuit Protection
Enhanced Power Good Output Detects Open Outputs in

Multi-VRM Power Systems
Overvoltage Protection Crowbar Protects Microprocessors

with No Additional External Components

APPLICATIONS
Desktop PC Power Supplies for:

Intel Pentium

AMD Athlon Processors

VRM Modules

®

4 Processors

Synchronous Buck Controller

ADP3163

FUNCTIONAL BLOCK DIAGRAM

2-/3-PHASE

DRIVER

CMP

PC

LOGIC

DAC+20%

POWER

GOOD

DAC+20%

g

m

REF

GND

SHARE

COMP

CT

VCC

UVLO

& BIAS

3.0V

REFERENCE

OSCILLATOR

SOFT

START

ADP3163

SET

RESET

CROWBAR

CMP

VID

DAC

PWM1
PWM2
PWM3

PGND

PWRGD

CS–
CS+

FB

GENERAL DESCRIPTION

The ADP3163 is a highly efficient multiphase synchronous buck
switching regulator controller optimized for converting a 5 V or
12 V main supply into the core supply voltage required by high
performance Intel processors. The ADP3163 uses an internal
5-bit DAC to read a voltage identification (VID) code directly
from the processor, which is used to set the output voltage between

1.1 V and 1.85 V. The ADP3163 uses a current mode PWM
architecture to drive the logic-level outputs at a programmable
switching frequency that can be optimized for VRM size and
efficiency. The phase relationship of the output signals can be
programmed to provide 2- or 3-phase operation, allowing for
the construction of up to three complementary buck switching
stages. These stages share the dc output current to reduce
overall output voltage ripple. An active current balancing func­tion ensures that all phases carry equal portions of the total load
current, even under large transient loads, to minimize the size of
the inductors.

ADOPT is a trademark of Analog Devices, Inc.
Pentium is a registered trademark of Intel Corporation.

REV. 0

Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties that
may result from its use. No license is granted by implication or otherwise
under any patent or patent rights of Analog Devices.

VID4 VID3 VID2 VID1

VID0

The ADP3163 also uses a unique supplemental regulation tech­nique called active voltage positioning (ADOPT) to enhance
load transient performance. Active voltage positioning results in
a dc/dc converter that meets the stringent output voltage specifi­cations for high performance processors, with the minimum
number of output capacitors and smallest footprint. Unlike
voltage-mode and standard current-mode architectures, active
voltage positioning adjusts the output voltage as a function of
the load current so that it is always optimally positioned for a
system transient. The ADP3163 also provides accurate and
reliable short circuit protection, adjustable current limiting, and
an enhanced Power Good output that can detect open outputs
in any phase for single or multi-VRM systems.

The ADP3163 is specified over the commercial temperature

range of 0°C to 70°C and is available in a 20-lead TSSOP package.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone] www.analog.com
Fax: [phone] © Analog Devices, Inc., 2001

ADP3163–SPECIFICA TIONS

Parameter Symbol Conditions Min Typ Max Unit

FEEDBACK INPUT

Accuracy V

1.1 V Output 1.091 1.1 1.109 V

1.6 V Output 1.587 1.6 1.613 V

1.85 V Output 1.835 1.85 1.865 V

Line Regulation ∆V

Input Bias Current I
Crowbar Trip Point V
Crowbar Reset Point % of Nominal Output 40 50 60 %
Crowbar Response Time t

REFERENCE

Output Voltage V
Output Current I

VID INPUTS

Input Low Voltage V
Input High Voltage V
Input Current I
Pull-Up Resistance R
Internal Pull-Up Voltage 2.7 3.0 3.3 V

OSCILLATOR

Maximum Frequency

2

Frequency Variation f

CT Charge Current I

ERROR AMPLIFIER

Output Resistance R
Transconductance g
Output Current I
Maximum Output Voltage V
Output Disable Threshold V
–3 dB Bandwidth BW

CURRENT SENSE

Threshold Voltage V

Input Bias Current I
Response Time t

to PWM Going Low

CURRENT SHARING

Output Source Current 2 mA

Output Sink Current 300 400 µA

Maximum Output Voltage V

PHASE CONTROL

Input Low Voltage V
Input High Voltage V

POWER GOOD COMPARATOR

Undervoltage Threshold V
Overvoltage Threshold V
Output Voltage Low V
Response Time 250 ns

FB

FB

FB

CROWBAR

CROWBAR

REF

REF

IL(VID)

IH(VID)

VID

VID

f

CT(MAX)

CT

CT

O(ERR)

m(ERR)

O(ERR)

COMP(MAX)

COMP(OFF)

ERR

CS(TH)

, I

CS+

CS–

CS

SHARE(MAX)

IL(PC)

IH(PC)

PWRGD(UV)

PWRGD(OV)

OL(PWRGD)IPWRGD(SINK)

(VCC = 12 V, I

= 150 A, TA = 0C to 70C, unless otherwise noted.)

REF

VCC = 10 V to 14 V 0.01 %

550 nA

% of Nominal Output 115 120 125 %

Overvoltage to PWM Going Low 400 ns

2.952 3.00 3.048 V

300 µA

0.8 V

2.0 V

VID(X) = 0 V 70 90 µA

33 43 kΩ

3000 kHz

T

= 25°C, CT = 150 pF 475 575 675 kHz

A

T

= 25°C, CT = 68 pF 850 1000 1250 kHz

A

T

= 25°C, CT = 47 pF 1100 1300 1500 kHz

A

T

= 25°C, VFB in Regulation 260 300 340 µA

A

T

= 25°C, VFB = 0 V 40 65 80 µA

A

1MΩ

2.0 2.2 2.45 mmho

FB Forced to 0 V 575 µA

FB Forced to V

– 3% 3.0 V

OUT

800 875 mV

COMP = Open 500 kHz

CS+ = VCC, 143 158 173 mV
FB Forced to V

OUT

– 3%

FB ≤ 750 mV 80 92 108 mV

0.8 V ≤ SHARE ≤ 1 V 0 5 mV
CS+ = CS– = VCC 1 5 µA
CS+ – (CS–) ≥ 173 mV 50 ns

FB Forced to V

– 3% 3.0 V

OUT

0.8 V

2.0 V

Percent of Nominal Output 75 80 85 %
Percent of Nominal Output 115 120 125 %

= 1 mA 375 525 mV

1

–2–

REV. 0

ADP3163

WARNING!

ESD SENSITIVE DEVICE

Parameter Symbol Conditions Min Typ Max Unit

PWM OUTPUTS

Output Voltage Low V
Output Voltage High V
Duty Cycle Limit Per Phase

2

OL(PWM)

OH(PWM)

DC PC = GND 50 %

I

PWM(SINK)

I

PWM(SOURCE)

PC = REF 33 %

SUPPLY

DC Supply Current

Normal Mode I
No CPU Mode I
UVLO Mode I

UVLO Threshold Voltage V

CC

CC(NO CPU)

CC(UVLO)

UVLO

VID4 – VID0 = Open 3.5 5.5 mA

VCC ≤ V

UVLO Hysteresis 0.5 0.8 1.0 V

NOTES

1

All limits at temperature extremes are guaranteed via correlation using standard Statistical Quality Control (SQC).

2

Guaranteed by design, not tested in production.

Specifications subject to change without notice.

ABSOLUTE MAXIMUM RATINGS*

VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to +15 V

CS+, CS– . . . . . . . . . . . . . . . . . . . . . . –0.3 V to VCC +0.3 V

All Other Inputs and Outputs . . . . . . . . . . . . –0.3 V to +10 V

Operating Ambient Temperature Range . . . . . . . 0°C to 70°C

Operating Junction Temperature . . . . . . . . . . . . . . . . . . 125°C

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

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143°C/W

θ

JA

Lead Temperature (Soldering, 10 sec) . . . . . . . . . . . . . 300°C

Vapor Phase (60 sec) . . . . . . . . . . . . . . . . . . . . . . . . . . . 215°C

Infrared (15 sec) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220°C

*This is a stress rating only; operation beyond these limits can cause the device to

be permanently damaged. Unless otherwise specified, all voltages are referenced
to PGND.

= 400 µA 100 500 mV

=400 µA 4.0 5.0 V

3.75 5.5 mA

, VCC Rising 350 500 µA

UVLO

5.9 6.4 6.9 V

PIN CONFIGURATION

RU-20

VID4

VID3

VID2

VID1

VID0

SHARE

COMP

GND

FB

CT

1

2

3

4

ADP3163

TOP VIEW

5

(NOT T O SCALE)

6

7

8

9

10

20

19

18

17

16

15

14

13

12

11

VCC

REF

PWM1

PWM2

PWM3

PC

PGND

CS–

CS+

PWRGD

ORDERING GUIDE

Model Temperature Range Package Description Package Option

ADP3163JRU 0°C to 70°C Thin Shrink Small Outline RU-20 (TSSOP-20)

CAUTION

ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily
accumulate on the human body and test equipment and can discharge without detection. Although
the ADP3163 features proprietary ESD protection circuitry, permanent damage may occur on
devices subjected to high-energy electrostatic discharges. Therefore, proper ESD precautions are
recommended to avoid performance degradation or loss of functionality.

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–3–

ADP3163

PIN FUNCTION DESCRIPTIONS

Pin Name Function

1–5 VID4 – Voltage Identification DAC Inputs. These pins are pulled up to an internal 3 V reference, providing a

VID0 Logic 1 if left open. The DAC output programs the FB regulation voltage from 1.1 V to 1.85 V. Leaving all five

DAC inputs open results in the ADP3163 going into a “No CPU” mode, shutting off its PWM outputs.

6 SHARE Current Sharing Output. This pin is connected to the SHARE pins of other ADP3163s in multiple VRM sys-

tems to ensure proper current sharing between the converters. The voltage at this output programs the output

current control level between CS+ and CS–.
7 COMP Error Amplifier Output and Compensation Point.
8 GND Ground. FB, REF and the VID DAC of the ADP3163 are referenced to this ground. This is a low current ground

that can also be used as a return for the FB pin in remote voltage sensing applications.
9 FB Feedback Input. Error amplifier input for remote sensing of the output voltage.
10 CT External capacitor CT connection to ground sets the frequency of the device.
11 PWRGD Open drain output that signals when the output voltage is outside of the proper operating range or when a phase

is not supplying current even if the output voltage is in specification.
12 CS+ Current Sense Positive Node. Positive input for the current comparator. The output current is sensed as a volt-

age at this pin with respect to CS–.
13 CS– Current Sense Negative Node. Negative input for the current comparator.
14 PGND Power Ground. All internal biasing and logic output signals of the ADP3163 are referenced to this ground.
15 PC Phase Control Input. This logic-level input determines the number of active phases and the duty cycle limit of

each phase.
16 PWM3 Logic-Level Output for the Phase 3 Driver.
17 PWM2 Logic-Level Output for the Phase 2 Driver.
18 PWM1 Logic-Level Output for the Phase 1 Driver.
19 REF 3.0 V Reference Output.
20 VCC Supply Voltage for the ADP3163.

ADP3163

VCC

REF

PWM1

PWM2

PWM3

PC

PGND

CS–

CS+

PWRGD

20

19

18

17

16

15

14

13

12

11

1.2V

20k

1F 100nF

V

FB

12V

100

100nF

5-BIT CODE

1

2

3

4

5

6

7

8

9

10

AD820

VID4

VID3

VID2

VID1

VID0

SHARE

COMP

GND

FB

CT

Figure 1. Closed-Loop Output Voltage Accuracy Test Circuit

Table I. PWM Outputs vs. Phase Control Code

Maximum

PC PWM3 PWM2 PWM1 Duty Cycle

REF ON ON ON 33%
GND OFF ON ON 50%

–4–

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Typical Performance Characteristics–ADP3163

10

1.0

FREQUENCY – MHz

0.1
0 10050

150 250200 300

CT CAPACITANCE – pF

TPC 1. Oscillator Frequency vs. Timing Capacitor (CT)

25

20

15

4.5

4.4

4.3

4.2

SUPPLY CURRENT – mA

4.1

4.0
0 1000500

OSCILLATOR FREQUENCY – kHz

1500 25002000 3000

TPC 2. Supply Current vs. Oscillator Frequency

TA = 25C

V

= 1.6V

OUT

10

NUMBER OF PARTS – %

5

0

–0.5

OUTPUT ACCURACY – % of Nominal

0 0.5

TPC 3. Output Accuracy Distribution

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–5–