ELANT EL7564CRE-T7, EL7564CRE-T13, EL7564CRE, EL7564CM-T13, EL7564CM Datasheet

EL7564C

Monolithic 4 Amp DC:DC Step-down Regulator

EL7564C

Features

• Integrated synchronous MOSFETs
and current mode controller

• 4A continuous output current

• Up to 95% efficiency

• 4.5V to 5.5V input voltage

• Adjustable output from 1V to 3.8V

• Cycle-by-cycle current limit

• Precision reference

• ±0.5% load and line regulation

• Adjustable switching frequency to
1MHz

• Oscillator synchronization
possible

• Internal soft start

• Over voltage protection

• Junction temperature indicator

• Over temperature protection

• Under voltage lockout

• Multiple supply start-up tracking

• Power good indicator

• 20-pin SO (0.300”) package

• 28-pin HTSSOP package

Applications

• DSP, CPU Core and IO Supplies

• Logic/Bus Supplies

• Portable Equipment

• DC:DC Converter Modules

• GTL + Bus Power Supply

Ordering Information

Part No Package

EL7564CM 20-Pin SO - MDP0027

EL7564CM-T13 20-Pin SO 13” MDP0027

EL7564CRE 28-Pin HTSSOP - MDP0048

EL7564CRE-T7 28-Pin HTSSOP 7” MDP0048

EL7464CRE-T13 28-Pin HTSSOP 13” MDP0048

Tape &

Reel Outline #

General Description

The EL7564C is an integrated, full-featured synchronous step-down
regulator with output voltage adjustable from 1.0V to 3.8V. It is capa­ble of delivering 4A continuous current at up to 95% efficiency. The
EL7564C operates at a constant frequency pulse width modulation
(PWM) mode, making external synchronization possible. Patented on­chip resistorless current sensing enables current mode control, which
provides cycle-by-cycle current limiting, over-current protection, and
excellent step load response. The EL7564C features power tracking,
which makes the start-up sequencing of multiple converters possible.
A junction temperature indicator conveniently monitors the silicon die
temperature, saving the designer time on the tedious thermal charac­terization. The minimal external components and full functionality
make this EL7564C ideal for desktop and portable applications.

The EL7564C is specified for operation over the -40°C to +85°C tem­perature range.

Typical Application Diagrams

C5

0.1µF
1

VREF

C4
390pF

R4

22Ω

C2

2.2nF

V

IN

5V

Typical Application Diagrams continued on page 3
Manufactured Under U.S. Patent No. 5,7323,974

330µF

C3

0.22µF

C1

2

3

4

5

6

7

8

9

10

SGND

COSC

VDD

VTJ

PGND

PGND

VIN

STP

STN

EL7564CM

(20-Pin SO)

VDRV

VHI

PGND

PGND

PGND

20

EN

19

FB

18

PG

17

16

15

LX

14

LX

13

12

11

C6 D1

0.22µF

L1

4.7µH

V

OUT

3.3V,
4A

C7 R2 C10

2.37k

330µF

2.2nF

R1
1kΩ

October 3, 2001

Note: All information contained in this data sheet has been carefully checked and is believed to be accurate as of the date of publication; however, this data sheet cannot be a “controlled document”. Current revisions, if any, to these

specifications are maintained at the factory and are available upon your request. We recommend checking the revision level before finalization of your design documentation.

© 2001 Elantec Semiconductor, Inc.

EL7564C

Monolithic 4 Amp DC:DC Step-down Regulator

EL7564C

Absolute Maximum Ratings (T

Supply Voltage between VIN or VDD and GND +6V

VLX Voltage VIN +0.3V

Input Voltage GND -0.3V, VDD +0.3V

VHI Voltage GND -0.3V, V

= 25°C)

A

LX

Storage Temperature -65°C to +150°C

Operating Ambient Temperature -40°C to +85°C

Operating Junction Temperature +135°C

+6V

Important Note:

All parameters having Min/Max specifications are guaranteed. Typ values are for information purposes only. Unless otherwise noted, all tests are at the
specified temperature and are pulsed tests, therefore: TJ = TC = TA.

DC Characteristics

V

= V

= 5V, TA = TJ = 25°C, C

DD

IN

Parameter Description Conditions Min Typ Max Unit

V

REF

V

REFTC

V

REFLOAD

V

RAMP

I

OSC_CHG

I

OSC_DIS

I

VDD+VDRVVDD+VDRV

I

VDD_OFF

V

DD_OFF

V

DD_ON

T

OT

T

HYS

I

LEAK

I

LMAX

R

DSON

R

DSONTC

I

STP

I

STN

V

PGP

V

PGN

V

PG_HI

V

PG_LO

V

OVP

V

FB

V

FB_LINE

V

FB_LOAD

V

FB_TC

I

FB

V

EN_HI

V

EN_LO

I

EN

Reference Accuracy 1.24 1.26 1.28 V

Reference Temperature Coefficient 50 ppm/°C

Reference Load Regulation 0<I

Oscillator Ramp Amplitude 1.15 V

Oscillator Charge Current 0.1V<V

Oscillator Discharge Current 0.1V<V

Supply Current VEN = 4V, F

V

Standby Current EN = 0 1 1.5 mA

DD

VDD for Shutdown 3.5 3.9 V

VDD for Startup 4 4.35 V

Over Temperature Threshold 135 °C

Over Temperature Hysteresis 20 °C

Internal FET Leakage Current EN = 0, LX = 5V (low FET), LX = 0V (high FET) 10 µA

Peak Current Limit 5 A
FET On Resistance Wafer level test only 30 60 mΩ

R

Tempco 0.2 mΩ/°C

DSON

Auxilliary Supply Tracking Positive Input
Pull Down Current

Auxilliary Supply Tracking Negative Input
Pull Up Current

Positive Power Good Threshold With respect to target output voltage 6 14 %

Negative Power Good Threshold With respect to target output voltage -14 -6 %

Power Good Drive High I

Power Good Drive Low IPG = -1mA 0.5 V

Over Voltage Protection 10 %

Output Initial Accuracy I

Output Line Regulation V

Output Load Regulation 0.5A< I

Output Temperature Stability -40°C < TA<85°C, I

Feedback Input Pull Up Current V

EN Input High Level 3.2 4 V

EN Input Low Level 1 V

Enable Pull Up Current VEN = 0 -4 -2.5 µA

= 1.2nF, unless otherwise specified.

OSC

V

STP

V

STN

PG

LOAD

IN

FB

<50µA -1 %

REF

<1.25V 200 µA

OSC

<1.25V 8 mA

OSC

= 120kHz 2 3.5 5 mA

OSC

= VIN/2 -4 2.5 µA

= VIN/2 2.5 4 µA

= 1mA 4 V

= 0A 0.960 0.975 0.99 V

= 5V, ∆V

= 10%, I

IN

<4A 0.5 %

LOAD

= 0A 0.5 %

LOAD

= 2A ±1 %

LOAD

= 0V 100 200 nA

2

EL7564C

Monolithic 4 Amp DC:DC Step-down Regulator

Closed Loop AC Electrical Characteristics

VS = V

= 5V, TA = TJ = 25°C, C

IN

Parameter Description Conditions Min Typ Max Unit

F

OSC

t

SYNC

M

t

BRM

t

LEB

D

SS

MAX

Oscillator Initial Accuracy 105 117 130 kHz

Minimum Oscillator Sync Width 25 ns

Soft Start Slope 0.5 V/ms

FET Break Before Make Delay 15 ns

High Side FET Minimum On Time 150 ns

Maximum Duty Cycle 95 %

Typical Application Diagrams (Continued)

V

IN

5V

= 1.2nF, unless otherwise specified.

OSC

C5

0.1µF

C4

390pF

R4

C3

22Ω

0.22µF

C2

2.2nF

1

VREF

2

SGND

3

COSC

4

VDD

5

VTJ

6

PGND

7

PGND

8

PGND

VDRV

VHI

28

EN

27

FB

26

PG

25

24

23

LX

22

LX

21

LX

C6 D1

0.22µF

L1

4.7µH
C7 R2 C10
330µF

2.37kΩ

V

OUT

3.3V,
4A

2.2nF

EL7564C

9

330µF

For the package information, please refer to the Elantec website at http://www.elantec.com/pages/package_outline.html

PGND

10

VIN

11

VIN

12

NC

13

STP

STN

(28-Pin HTSSOP)

EL7564CRE

PGND

PGND

20

LX

19

LX

18

LX

17

NC

16

1514

3

R1
1kΩ

EL7564C

Monolithic 4 Amp DC:DC Step-down Regulator

EL7564C

Pin Descriptions

Pin Number Pin Name Pin Function

1 VREF Bandgap reference bypass capacitor; typically 0.1µF to SGND

2 SGND Control circuit negative supply or signal ground

3 COSC Oscillator timing capacitor (see performance curves)

4 VDD Control circuit positive supply; normally connected to VIN through an RC filter

5 VTJ Junction temperature monitor; connected with 2.2nF to 3.3nF to SGND

6 PGND Ground return of the regulator; connected to the source of the low-side synchronous NMOS power FET

7 PGND Ground return of the regulator; connected to the source of the low-side synchronous NMOS power FET

8 VIN Power supply input of the regulator; connected to the drain of the high-side NMOS power FET

9 STP Auxilliary supply tracking positive input; tied to regulator output to synchronize start up with a second supply; leave open

10 STN Auxilliary supply tracking negative input; connect to output of a second supply to synchronize start up; leave open for

11 PGND Ground return of the regulator; connected to the source of the low-side synchronous NMOS power FET

12 PGND Ground return of the regulator; connected to the source of the low-side synchronous NMOS power FET

13 PGND Ground return of the regulator; connected to the source of the low-side synchronous NMOS power FET

14 LX Inductor drive pin; high current output whose average voltage equals the regulator output voltage

15 LX Inductor drive pin; high current output whose average voltage equals the regulator output voltage

16 VHI Positive supply of high-side driver; boot strapped from VDRV to LX with an external 0.22µF capacitor

17 VDRV Positive supply of low-side driver and input voltage for high side boot strap

18 PG Power good window comparator output; logic 1 when regulator output is within ±10% of target output voltage

19 FB Voltage feedback input; connected to external resistor divider between VOUT and SGND; a 125nA pull-up current forces

20 EN Chip enable, active high; a 2µA internal pull up current enables the device if the pin is left open; a capacitor can be added

for stand alone operation; 2µA internal pull down current

stand alone operation; 2µA internal pull up current

VOUT to SGND in the event that FB is floating

at this pin to delay the start of converter

4

Monolithic 4 Amp DC:DC Step-down Regulator

Typical Performance Curves (20-Pin SO Package)

*Note: The 28-Pin HTSSOP Package Offers Improved Performance

EL7564C

EL7564C

*Efficiency vs IO (VIN=5V)

100

95
90
85
80
75

Efficiency (%)

70
65
60

0 43.532.5210.5 1.5

*Power Loss vs IO (VIN=5V)

2

1.6

1.2

0.8

Power Loss (Watts)

0.4

0

0 43.532.5210.5 1.5

VO=2.8V

VO=1.8V

Load Current IO (A)

Output Current IO (A)

VO=3.3V

VO=3.3V

VO=2.8V

VO=1.8V

*Efficiency vs IO (VO=3.3V)

100

95
90
85
80
75

Efficiency (%)

70
65
60

0 43.532.5210.5 1.5

Load Regulations (VO=3.3V)

3.325

3.315

3.305

3.295

Output Voltage (V)

3.285

3.275

0.5 43.532.51.51 2

VIN=4.5V

VIN=5V

VIN=5.5V

Load Current IO (A)

VIN=5.5V

VIN=5V

VIN=4.5V

Load Current IO (A)

Line Regulation (VO=3.3V)

3.325

3.315

3.305

(V)

O

V

3.295

3.285

3.275

IO=0.5A

IO=2A

IO=4A

4.5 5.554.75 5.25
VIN (V)

V

vs Die Temperature

REF

1.27

1.268

1.266

1.264

(V)

REF

1.262

V

1.26

1.258

1.256

-50 150-10 30 70 110
Die Temperature (°C)

5

EL7564C

Monolithic 4 Amp DC:DC Step-down Regulator

EL7564C

Typical Performance Curves

*Note: The 28-Pin HTSSOP Package Offers Improved Performance

Oscillator Frequency vs Temperature

360
350
340

IO=4A

330
320
310

IO=0A

300

Oscillator Frequency (KHz)

290
280

-40 80-20 20 40 60

VTJ vs Junction Temperature

1.5

1.3

VTJ

1.1

0.9
0 15025

Current Limit vs T

8

7

6

(A)

LMT

I

5

4

0

Temperature (°C)

Junction Temperature (°C)

J

VIN=5.5V VIN=5V

VIN=4.5V

Switching Frequency vs C

1000

900
800
700
600

(KHz)

S

500

F

400
300
200
100

100 1000200 400 600 800

*θJA vs Copper Area
(20-Pin SO Package)

50

46

42

38

Thermal Resistance (°C/W)

34

Test Condition:
Chip in the center of copper area

12550 75 100

30

1 41.5 2.5 3.5

PCB Copper Heat-Sinking Area (in2)

Switching Waveforms
VIN=5V, VO=3.3V, IO=4A

∆V

IN

V

LX

i

L

∆V

O

OSC

C

(pF)

OSC

with no airflow

with 100 LFPM airflow

1 oz. copper PCB used

2 3

900300 500 700

3

-40 120-20 40 100

0 806020

TJ (°C)

6