US2075 [UNISEM]

PWM SWITCHER CONTROLLER & 7.5A LOW DROPOUT REGULATOR COMBO; PWM SWITCHER控制器及7.5A低压差稳压器COMBO


型号：	US2075
厂家：	UNISEM
描述：	PWM SWITCHER CONTROLLER & 7.5A LOW DROPOUT REGULATOR COMBO PWM SWITCHER控制器及7.5A低压差稳压器COMBO 稳压器控制器
文件：	总4页 (文件大小：45K)
中文：	中文翻译
下载：	下载PDF数据表文档文件

US2075

PWM SWITCHER CONTROLLER & 7.5A

LOW DROPOUT REGULATOR COMBO

PATENTPENDING

FEATURES

DESCRIPTION

The US2075 eliminates the need for a

seperate switching controller IC

The US2075 is a dual function IC combining a switching

controller and a 7.5A low dropout regulator all in a com-

Minimum part count allows lower system cost

Fixed 3.30V/7.5A LDO on board

On board MOSFET driver

Fastest transient response of any controller

method. ( 0 to 100% Duty Cycle in 100 nS )

1% internal voltage reference

Internal Thermal shutdown

Internal Under Voltage Lockout protects

MOSFET during start-up

pact 7 pin TO220 and TO263 surface mount pack-

ages providing a total solution for dual supply proces-

sor applications such as an Intel P55C ä , AMD K6ä ,

as well as Cyrix 6X86Lä and the M2ä processors.

Typically in these applications a dual supply regulator

converts 5V to 3.3V for I/O supply and a jumper pro-

grammable supply of 2.8V to 3.5V for CORE supply .The

linear regulator portion in the US2075 is a fixed 3.30V

output and has a minimum of 7.5A current capability

designed to provide ample current for most applications

while the switching regulator controller uses the 5V sup-

ply to power the controller and the 12V supply to drive

the power MOSFET, allowing a low cost N- MOS switch

to be used. The IC also includes an error comparator for

fastest transient response, a precise voltage reference

for setting the output voltage as well as a direct drive of

the MOSFET for the minimum part count.

APPLICATIONS

Dual supply low voltage processor applications,

such as: P55Cä ,CYRIX M2ä , POWER PCä and

AMD

TYPICAL APPLICATION

Vout

Vhyst

Gnd

Vfb

3.30V / 7.5A

US2075

V12

Drv

2075ap1a-1.0

2.8V / 10A

12V

Typical application of US2075 in a flexible mother board designed for Intel P55ä ,P54ä

AMD K5,K6ä as well as Cyrix M1ä and M2ä applications.

Notes: P54C,P55C are trade marks of Intel Corp. K5 & K6 are trade marks of AMD corp. Cyrix 6X86L,M1,M2 are trade marks of Cyrix

Corp. Power PC is trade mark of IBM Corp.

PACKAGE ORDER INFORMATION

Tj (°C)

7 PIN PLASTIC

TO220 (T)

7 PIN PLASTIC

TO263 (M)

0 TO 125

US2075CT

US2075CM

Rev. 1.2

4/26/98

4-1

US2075

ABSOLUTE MAXIMUM RATINGS

12V Supply Voltage ............................................................. 14V

5V Supply Voltage .............................................................. 7V

LDO Power Dissipation .................................... Internally Limited

FB Pin Voltage........................................................

-0.3V to 5V

Storage Temperature Range ................................. -65 TO 150°C

Operating Junction Temperature ............................... O TO 150°C

PACKAGE INFORMATION

7 PIN PLASTIC TO220 (T)

7 PIN PLASTIC TO263 (M)

FRONT VIEW

Vout

Vhyst

Gnd

Vout

Vhyst

Gnd

Vfb

V12

Drv

Vfb

V12

Drv

qJT=2.7°C/W qJA=60°C/W

qJA=35°C/W for 1" Square pad

ELECTRICAL SPECIFICATIONS

Unless otherwise specified the following specification applies over,V5=5V,V12=12V,and Tj=0 to 125°C.Low duty

cycle pulse testing are used which keeps junction and case temperatures equal to the ambient temperature.

LDO Section

PARAMETER

SYM TEST CONDITION

MIN TYP

MAX UNITS

Output Voltage

VOUT Io=0mA

3.400

Line Regulation

Io=0mA, 4.75<V5<6V

0A<Io<7.5A

dVo=0.995*VOUT

30 mS Pulse,V5=5V

f=120HZ ,Co=25uF Tan

Io=1A

0.2

0.5

%/W

Load Regulation (note 1)

Maximum Output Current

Thermal Regulation

Ripple Rejection

IMAX

7.5

0.01

0.02

Switching Controller Section

PARAMETER

SYM TEST CONDITION

MIN TYP

1.237 1.250 1.262

Includes Temp & line,4.75 to 5.25V 1.225 1.250 1.275

MAX UNITS

F.B Voltage Initial Accuracy

F.B Voltage Total Variation

F.B Input Bias Current

Min On Time

Vfb

Ifb

TJ=25°C

Vfb=1.25V

-2

Vfb is sq wave with 300 ns on

time and 2 uS off time

Vfb is sq wave with 300 ns off

time and 2 uS on time

Isource=500uA,Vfb=1.5V

Isink=500uA,Vfb=1V

Vfb=1V

400

600

800

Min Off Time

400

800

Vhyst pin output-HI

Vhyst pin output-LO

Supply Current

Icc

Maximum Duty Cycle

Minimum Duty Cycle

Gate Drive Rise/Fall Time

Dmax Vfb=1V

Dmin Vfb=1.5V

Vgate Load=IRL3303

100

Rev. 1.2

4/26/98

4-2

US2075

Note 1 : Low duty cycle pulse testing with Kelvin con-

nections are required in order to maintain accurate data.

PIN DESCRIPTIONS

PIN # PIN SYMBOL PIN DESCRIPTION

Vfb

Vout

A resistor divider from this pin to the output of the switching regulator and

ground sets the core supply voltage.

The output of the linear regulator. A minimum of a 10uF capacitor must be

connected from this pin to ground to insure stability. This voltage is set at 3.30V typ.

The input pin of the regulator. Typically a large storage capacitor is connected from

this pin to ground to insure that the input voltage does not sag below the minimum

drop out voltage during the load transient response. This pin must always be 1.3V

higher than Vout in order for the device to regulate properly.

Gnd

Drv

This pin is connected to the IC substrate and must be connected to the lowest

potential in the system. It is also connected to the Tab of the package. A high

frequency capacitor must be connected from V12 to this pin to insure proper operation.

The PWM output of the switching controller. This pin is a totem pole drive that is

connected to the gate of the power MOSFET. A resistor may be placed from this

pin to the gate in order to reduce switching noise.

Vhyst

V12

A resistor is connected from this pin to the Vfb pin to set the output ripple voltage.

See application note for more details.

This pin is connected to the 12V supply voltage A high frequency cap must be

connected from this pin to the GND pin of the IC.

BLOCK DIAGRAM

V12

Vhyst

Vfb

Vout

UVLO

Drv

Vref

PWM Control

1.25V

7.5A LDO

Gnd

2075blk1-1.0

Figure 1 - Simplified block diagram of the US2075

Rev. 1.2

4/26/98

4-3

US2075

TYPICAL APPLICATION

Cache & Chip Set

CPU I / O

Vhyst

Gnd

Vfb

JP7

R6A

V12

Drv

Core Supply

R8B

R8C

R7E

2050ta3d

12V

JP2

JP3

JP4

JP5

Output

Voltage

3.5

3.4

3.3

3.2

3.1

3.0

2.9

2.8

2.7

2.6

2.5

2.4

2.3

2.2

2.1

R7A

R7B

JP3

R7C

R7D

JP2

JP4

JP5

Figure2- Typical application of US2075 in a

flexible motherboard with the 4 bit VID output voltage selection.

This circuit uses a single jumper that programs the output volt-

age in 16 steps with 0.1V steps from 2V to 3.5V, designed for

Intel P55ä ,P54ä , AMD K5 & K6ä as well as Cyrix M1ä and

M2ä applications. The jumper JP7 selects between single sup-

ply and dual supply processors.

2.0

Ref Desig Description

Qty

Part #

US2075CT (TO220)

US2075CM (TO263) (note 1)

IRL3303 (TO220)

IRL3103S (TO263) (note 1)

MBR1045CT (TO220)

MBRB1545CT (TO263) (note1)

Core:T50-18,L=4 uH

Manufacturer

Unisem

LDO/Switcher IC

MOSFET

International

Rectifier

Motorola

Schottky Diode

Inductor

Micro Metal

(core)

Turns: 10T, 18 AWG

Inductor

L=2 uH

Resistor

Capacitor

Heat Sink

22 ohm,5%, SMT 1206 size

10 ohm, 5%, SMT 1206 size

806 ohm,1%, SMT 0805 size

90.9 kohm,1%, SMT 0805 size

1.24 kohm,1%, SMT 0805 size

2.49 kohm,1%, SMT 0805 size

4.99 kohm,1%, SMT 0805 size

10 kohm,1%, SMT 0805 size

1.30 kohm,1%, SMT 0805 size

324 kohm,1%, SMT 0805 size

10pF,Ceramic, SMT 0805 size

1 uF,Ceramic, SMT 0805 size, Z5U

EEUFA1A681L, 680uF,10V, Elect

470pF,Ceramic, SMT 0805 size

6MV1500GX, 1500uF,6.3V, Elect

EEUFA1A681L, 680uF,10V, Elect

6MV1500GX, 1500uF,6.3V, Elect

For MOSFET , 577002

R8C

R8B

R7A

R7B

R7C

R7D

R7E

R6A

Panasonic

Sanyo

Panasonic

Sanyo

Aavid

HS1

HS2

HS3

For Schottky Diode , 577002

For US2075 , 507222 (I/O Load Current<5A)

576602 (I/O Load Current< 3.5A)

Note 1: For the applications where it is desirable to eliminate the heat sink, the US2075CM for U1 when load current is

less than 1.5A, the IRL3103S for Q2 and MBR1545CT for D1 in TO263 packages with minimum of 1" square copper pad

can be used.

Rev. 1.2

4/26/98

4-4

US2075 [UNISEM]

相关型号：

US2075A

US2075A-S08-R

US2075A-S08-T

US2075AG-S08-R

US2075AL-S08-R

US2075AL-S08-T

US2075A_09

US2075A_15

US2075A_16

US2075B-S08-R

US2075B-S08-T

US2075BL-S08-R