Fairchild Semiconductor RC5058 Datasheet

www.fairchildsemi.com

RC5058

High Performance Programmable Synchronous
DC-DC Controller for Multi-Voltage Platforms

Features

•P rogrammable output for Vcore from 1.3V to 3.5V using

an integrated 5-bit DAC
Controls adjustable linears for Vagp (selectable 1.5V/3.3V),

•
Vclock (2.5V), and Vtt (1.5V) or Vnorthbridge (1.8V)

• Meets VRM specification with as few as 5 capacitors

• Meets 1.550V +40/-70mV over initial tolerance,
temperature and transients

• Remote sense

• Programmable Active Droop™ (Voltage Positioning)

• Drives N-Channel MOSFETs

• Overcurrent protection using MOSFET sensing

• 85% efficiency typical at full load

• Integrated Power Good and Enable/Soft Start functions

• 24 pin SOIC package

Block Diagram

+3.3V

+1.5V

+2.5V

9

+

10

VCCP

11

+

12

OSC

REF

­PWRGD,

OCL

REF

-

PWRGD,
OCL

OCL

VCCA

-

+

Applications

• Power supply for Pentium

• Power supply for Pentium III Whitney Platform

• VRM for Pentium III processor

• Programmable multi-output power supply

®

III Camino Platform

Description

The RC5058 is a synchronous mode DC-DC controller IC
which provides a highly accurate, programmable set of output
voltages for multi-voltage platforms such as the Intel Camino,
and provides a complete solution for the Intel Whitney and other
high-performance processors. The RC5058 features remote
voltage sensing, independently adjustable current limit, and a
proprietary Programmable Active Droop
transient response. The RC5058 uses a 5-bit D/A converter
to program the output voltage from 1.3V to 3.5V. The RC5058
uses a high level of integration to deliver load currents in excess

+5V

21

-

+

-

+

19

18

20
24

1

R

R

S

VCCP
HIDRV

D

+12V

™

for optimal converter

+5V

15

14

+

V

-

5-Bit

DAC

VID2

PWRGD, OCL

VID4

VID3

3.3/1.5V

Pentium is a registered trademark of Intel Corporation. Programmable Active Droop is a trademark of Fairchild Semiconductor.

13

87654

VID0

VID1

-

+

1.24V

Reference

-

+

3

GNDA

Digital

Control

16

ENABLE/SS

Power

Good

2

23

22

17

LODRV

GNDP

PWRGD

VCC

Rev. 1.0.0

2

RC5058 PRODUCT SPECIFICATION

of 16A from a 5V source with minimal external circuitry.
Synchronous-mode operation offers optimum efficiency over
the entire specified output voltage range. An on-board precision
low TC reference achieves tight tolerance voltage regulation
without expensive external components, while Programmable
Active Droop

™

permits exact tailoring of voltage for the most
demanding load transients. The RC5058 includes linear regulator
controllers for Vtt termination (1.5V), Vclock (2.5V), and
Vnorthbridge (1.8V) or Vagp (selectable 1.5V/3.3V), each adjust­able with an external divider. The RC5058 also offers integrated
functions including Power Good, Output Enable/Soft Start and
current limiting, and is available in a 24 pin SOIC package.

Pin Definitions

Pin

Number Pin Name Pin Function Description

1 HIDRV

2SW

3 GNDA

4-8 VID0-4

9 VTTGATE Gate Driver for VTT Transistor. For 1.5V output.
10 VTTFB
11 VCKGATE Gate Driver for VCK Transistor. For 2.5V output.
12 VCKFB
13 VAGPFB
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

17 PWRGD

18 ILIM

19 DROOP
20 VFB

21 VCCA
22 GNDP
23 LODRV

24 VCCP

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".

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

DROOP and ILIM pins allows FET sensing for Vcc current.

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.

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.

Voltage Feedback for VTT.

Voltage Feedback for VCK.
Voltage Feedback for VAGP.

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

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.

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.

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

Analog VCC. Connect to system 5V supply and decouple with a 0.1µF ceramic capacitor.
Power Ground. Return pin for high currents flowing in pin 24 (VCCP).
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".

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

decouple with a 1µF ceramic capacitor.

Pin Assignments

HIDRV

SW

GNDA

VID4
VID3
VID2

VID1

VID0

VTTGATE

VTTFB

VCKGATE

VCKFB

1
2
3
4
5
6
7
8
9
10
11
12

RC5058

24
23
22
21
20
19
18
17
16
15
14
13

VCCP
LODRV
GNDP
VCCA
VFB
DROOP
ILIM
PWRGD
SS/ENABLE
TYPEDET
VAGPGATE
VAGPFB

REV. 1.0.0 6/30/00

PRODUCT SPECIFICATION RC5058

Absolute Maximum Ratings

Supply Voltage VCCA to GND 13.5V
Supply Voltage VCCP to GND 15V
Voltage Identification Code Inputs, VID0-VID4 VCCA
All Other Pins 13.5V
Junction Temperature, T

J

150°C
Storage Temperature -65 to 150°C
Lead Soldering Temperature, 10 seconds 300°C
Thermal Resistance Junction-to-ambient, Θ

Note:

1. Component mounted on demo board in free air.

JA

1

75°C/W

Recommended Operating Conditions

Parameter Conditions Min. Typ. Max. Units

Supply Voltage VCCA 4.5 5 5.25 V
Input Logic HIGH 2.0 V
Input Logic LOW 0.8 V
Ambient Operating Temperature 0 70 °C
Output Driver Supply, VCCP 10.8 12 13.2 V

Electrical Specifications

(V

= 5V, V

CCA

The • denotes specifications which apply over the full operating temperature range.

Parameter Conditions Min. Typ. Max. Units
VCC Regulator

Output Voltage See Table 1 • 1.3 3.5 V
Output Current 18 A
Initial Voltage Setpoint I

Output Temperature Drift T

Line Regulation V
Internal Droop Impedance I
Maximum Droop 60 mV
Output Ripple 20MHz BW, I
Total Output Variation,

Steady State

Total Output Variation,

Transient
Short Circuit Detect Current • 45 50 60 µA
Efficiency I
Output Driver Rise & Fall Time See Figure 3 50 nsec
Output Driver Deadtime See Figure 3 50 nsec

CCP

2

= 12V, V

1

= 2.0V, and T

OUT

= +25°C using circuit in Figure 1 unless otherwise noted.)

A

= 0.8A,V

LOAD

= 0 to 70°C,V

A

= 4.75V to 5.25V • -4 mV/V

IN

= 0.8A to 12.5A 13.0 14.4 15.8 K Ω

LOAD

V

= 2.000V

OUT

V

= 1.550V

OUT

I

= 0.8A to 18A, V

LOAD

= 18A, V

LOAD

= 2.400V

OUT

V

= 2.000V

OUT

V

= 1.550V

OUT

= 2.000V

OUT

V

= 1.550V

OUT

= 18A 11 mVpk

LOAD

3

= 2.000V

OUT

V

= 1.550V

OUT

= 2.0V 85 %

OUT

3

2.397

2.000

1.550

•

•

••1.940

1.480

••1.900

1.480

2.424

2.020

1.565
+8

+6

2.454

2.040

1.580

2.070

1.590

2.100

1.590

V
V
V

mV
mV

V

V

REV. 1.0.0 6/30/00

3

4

≤

≤

≤

≤

RC5058 PRODUCT SPECIFICATION

Electrical Specifications

(V

CCA

= 5V, V

CCP

= 12V, V

OUT

(Continued)

= 2.0V, and T

= +25°C using circuit in Figure 1 unless otherwise noted.)

A

The • denotes specifications which apply over the full operating temperature range.

Parameter Conditions Min. Typ. Max. Units

Duty Cycle 0 100 %
5V UVLO • 3.74 4 4.26 V
12V UVLO • 7.65 8.5 9.35 V
Soft Start Current • 5 10 17 µA

VTT Linear Regulator

Output Voltage I

2A • 1.455 1.5 1.545 V

LOAD

Under Voltage Trip Level Over Current 80 %V

VCLK Linear Regulator

Output Voltage I

2A • 2.375 2.5 2.625 V

LOAD

Under Voltage Trip Level Over Current 80 %V

VAGP Linear Regulator

Output Voltage I
Output Voltage I

2A, TYPEDET=0V • 1.425 1.5 1.575 V

LOAD

2A, TYPEDET=OPEN • 3.135 3.3 3.465 V

LOAD

Under Voltage Trip Level Over Current 80 %V

Common Functions

Oscillator Frequency • 255 310 345 kHz
PWRGD Threshold Logic HIGH, All Outputs

Linear Regulator Under Voltage

Logic LOW, Any Output
Over Current 30 µsec

•

92

•

88

108
112

Delay Time

Notes:

1. Steady State Voltage Regulation includes Initial Voltage Setpoint, Droop, Output Ripple and Output Temperature Drift and is
measured at the converter’s VFB sense point.

2. As measured at the converter’s VFB sense point. For motherboard applications, the PCB layout should exhibit no more than

0.5m Ω trace resistance between the converter’s output capacitors and the CPU. Remote sensing should be used for optimal
performance.

3. Using the VFB pin for remote sensing of the converter’s output at the load, the converter will be in compliance with Intel’s VRM 8.4
specification of +50, –80mV. If Intel specifications on maximum plane resistance from the converter’s output capacitors to the CPU
are met, the specification of +40, –70mV at the capacitors will also be met.

%V

O

O

O

OUT

REV. 1.0.0 6/30/00

PRODUCT SPECIFICATION RC5058

Table 1. Output Voltage Programming Codes

VID4 VID3 VID2 VID1 VID0 Nominal V

01111 1.30V
01110 1.35V
01101 1.40V
01100 1.45V
01011 1.50V
01010 1.55V
01001 1.60V
01000 1.65V
00111 1.70V
00110 1.75V
00101 1.80V
00100 1.85V
00011 1.90V
00010 1.95V
00001 2.00V
00000 2.05V
11111 2.0V
11110 2.1V
11101 2.2V
11100 2.3V
11011 2.4V
11010 2.5V
11001 2.6V
11000 2.7V
10111 2.8V
10110 2.9V
10101 3.0V
10100 3.1V
10011 3.2V
10010 3.3V
10001 3.4V
10000 3.5V

OUT

Note:

1. 0 = processor pin is tied to GND.
1 = processor pin is open.

REV. 1.0.0 6/30/00

5

RC5058 PRODUCT SPECIFICATION

V

Typical Operating Characteristics

(V

= 5V, V

CCA

88
86
84
82
80
78
76

Efficiency (%)

74
72
70
68
66
64

0 3 6 9 12 15 18

= 12V, and T

CCP

V

Efficiency vs. Output Current

CPU

V

= 1.550V

OUT

Output Current (A)

= +25°C using circuits in Figure 1, unless otherwise noted.)

A

Droop, V

2.04

V

= 2.000

OUT

2.03

2.02

2.01

2.00

1.99

(V)

1.98

OUT

V

1.97

1.96

1.95

1.94
0 3 6 9 12 15 18

= 2.0V, RD = 8K Ω

CPU

Output Current (A)

6

CPU Output Voltage vs. Output Current

3.5

3.0

2.5

2.0

(V)

OUT

1.5

Output Programming, VID4 = 0

2.1

1.9

1.7

(V)

1.5

CPU

V

1.3

V

1.0

0.5
0

0 5 10 15 20 25

Output Current (A)

3.5

3.0

2.5

(V)

2.0

CPU

V

1.5

Output Programming, VID4 = 1

1.1

1.30 1.40 1.50 1.60 1.70 1.80 1.90 2.00

DAC Setpoint

1.0

2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 3.0 3.1 3.2. 3.3 3.4 3.5

DAC Setpoint

REV. 1.0.0 6/30/00