NIKO N2576S, N2576S-3.3, N2576S-5, N2576T, N2576T-3.3 Datasheet

NIKO-SEM

5 Bit Programmable Synchronous

Buck Converter with Dual LDOs

GENERAL DESCRIPTION

FEATURES

N3004

The N3004 is a 5 bit TTL-compatible input,
digital-to-analog (DAC) programmable, syn­chronous buck converter with dual LDOs
controller designed specifically to power the
Pentium ® II as well as the next generation of
P6 family or other high performance core
logic in desktop personal computer and file
servers CPU applications.
The N3004 switching section provides pro­grammability of output voltage from 1.3V to

2.05V in 50mV steps and 2.0V to 3.5V in 100
mV increments and the linear sections use
external N-Channel power MOSFETs to
provide fixed output voltages of 1.5V for GTL
bus and 2.5V for clock.
The N3004 monitors all the output voltages.
A signal Power-Good signal is issued when
the core is within ±15% of the DAC setting.
Additional features are built-in over-voltage,
over-current protections for the core output
and logic compatible shutdown.

z Synchronous operation with high efficiency
z TTL-compatible 5 bit DAC, output voltage

selection from 1.3V to 3.5V programmable

z Fast transient response
z Provides 2 regulated voltages, 1.5V and

2.5V for linear section

z Power-Good output voltage monitor
z Over-Voltage and Over-Current protection
z Logic level enable input
z High performance and low cost solution

APPLICATIONS

z Powering Pentium, ® II, III or Deschutes,
K6 and other advanced processor
z High power DC to DC controller with triple
output supplies

TYPICAL APPLICATION

ENABLE

VID 0~4

POWER-GOOD

12V

+

LINEAR

SECTION

SWITCHING

SECTION

3.3V

5V

+

VCORE

+

1.5V
GTC

+

+

+

BUS

2.5V
CLOCK

N3004, Motherboard Power Regulation for Computers

1

JAN-10-Y02

NIKO-SEM

5 Bit Programmable Synchronous

N3004

Buck Converter with Dual LDOs

ABSOLUTE MAXIMUM RATINGS

PARAMETER VALUE

Supply Voltage (V5 to GND) 10V
Supply Voltage (V12 to GND) 20V
Thermal Resistance Junction to Case, θJC
Thermal Resistance Junction to Ambient, θJA

25°C/W

85°C/W
Operating Temperature Range 0 to 70°C
Storage Temperature Range -65 to +150°C
Junction Operating Temperature 0 to +125°C
Lead Temperature (Soldering, 10 Seconds) 300°C

ELECTRICAL SPECIFICATIONS

<Unless otherwise specified: V5 = 5V, V12 = 12V and TA = 25°C>

PARAMETER CONDITIONS MIN TYP MAX UNITS

SWITCHING SECTION

DAC Output Voltage (Note 1) 0.99Vs Vs 1.01Vs V
DAC Output Line Regulation 0.1 %
DAC Output Temp. Variation 0.5 %
VID Input LO 0.4 V
VID Input HI 2 V
VID Input Internal Pull-Up

Resistor to V5

27

KΩ

POWER GOOD SECTION

Power Good Threshold Voltage

85 115 %

Power Good Output LO IL = 3mA 0.4 V
Power Good Output HI

RL = 5KΩ pull up to 5V

4.8 V

SOFT START SECTION

Soft Star Current CS+ =0V, CS- =5V 10

μA

UVLO SECTION

UVLO Threshold for V12 Supply ramping up 9.2 10 10.8 V
UVLO Hysterises for V12 0.3 0.4 .05 V
UVLO Threshold for V5 Supply ramping up 4.1 4.3 4.5 V
UVLO Hysterises for V5 0.2 0.3 0.4 V

ERROR COMPARATOR SECTION

Input Bias Current 2

μA

Input Offset Voltage -2 +2 mV
Delay to Output V

= 10mV 100 nS

DIFF

2

JAN-10-Y02

NIKO-SEM

5 Bit Programmable Synchronous

N3004

Buck Converter with Dual LDOs

PARAMETER CONDITIONS MIN TYP MAX UNITS

CURRENT LIMIT SECTION

C.S Threshold Set Current 160 200 240

μA

C.S Comparator Offset Voltage -5 +5 mV
Hiccup Duty Cycle

Css = 0.1μF

2 %

SUPPLY CURRENT

Operating Supply Current CL=3000 pF
V5 20
V12 14 mA

OUTPUT DRIVERS SECTION

Rise Time CL = 3,000pF 60 100 nS
Fall Time CL = 3,000pF 60 130 nS
Dead Band Time CL = 3,000pF 100 200 300 nS

OSCILLATOR SECTION

Oscillator Frequency CL = 150pF 220 KHz
Oscillator Valley 0.2 V
Oscillator Peak V5 V

LINEAR SECTIONS

V

& V

FB1

Input Bias Current 2

I

DRIVER1

Note 1: Vs refers to the set point voltage given in Table 1.

1.40 1.50 1.60 V

FB2

or I

DRIVER2

50 mA

μA

PIN CONFIGURATIONS

3

JAN-10-Y02