Microsemi Corporation LX8587-33CP, LX8587-33CDD, LX8587-15CP, LX8587-15CDD, LX8587A-15CP Datasheet

		LIN D O C #: 8587
		LX8587-xx/8587A-xx
		3 A L O W D R O P O U T P O S I T I V E R E G U L AT O R S
T H E I N F I N I T E P O W E R O F I N N O V A T I O N		P R O D U C T I O N D A T A S H E E T

D E S C R I P T I O N

The LX8587/8587A series ICs are low dropout three-terminal positive regulators with a nominal 3A output current. Pentium® Processor and Power PCTM applications requiring fast transient response are ideally suited for this product family.

The LX8587A is guaranteed to have

<1.2V dropout at 3A and the LX8587

<1.3V at the same current, making

them ideal to provide well-regulated outputs of 2.5V to 3.6V using a 5V input supply. Fixed versions are also available and specified in the Available Options table below.

Current limit is trimmed above 3.1A to ensure adequate output current and controlled short-circuit current. On-chip thermal limiting provides protection against any combination of overload conditions that would create excessive junction temperatures.

The LX8587/87A family of products are available in both TO-220 through-hole as well as TO-263 surface-mount packages. For higher current applications, see the LX8585 and LX8584 data sheets.

IMPORTANT: For the most current data, consult LinFinity's web site: http://www.linfinity.com.

P R O D U C T H I G H L I G H T

TYPICAL APPLICATION OF THE LX8587/87A IN A 5V TO 3.3V MOTHERBOARD APPLICATION

VIN Ο 4.75	LX8587A	3.3V/3A
1500µF	121	2x 1500µF
		Sanyo
6MV1500GX
		6MV1500GX
	200

K E Y F E AT U R E S

■Three-Terminal Adjustable Or Fixed Output

■Guaranteed ≤ 1.2V Headroom At 3A (LX8587A)

■Guaranteed ≤ 1.3V Headroom At 3A (LX8587)

■Output Current Of 3A

pFast Transient Response

p1% Voltage Reference Initial Accuracy

pOutput Short Circuit Protection

pBuilt-In Thermal Shutdown

A P P L I C AT I O N S

■Pentium Processor Supplies

■Power PC Supplies

■Microprocessor Supplies

■Low Voltage Logic Supplies

■Post Regulator For Switching Supply

■ASIC & Low Voltage Chipset Supplies

■Graphics & Sound Cards

■Processor I/O Supply

AVA I L A B L E O P T I O N S P E R PA R T #

	Part #		Output
			Voltage
	LX8587/87A-00		Adjustable
	LX8587/87A-15		1.5V
	LX8587/87A-33		3.3V

The output capacitors must be low ESR and low ESL type for good transient response.

Other voltage options may be available — Please contact factory for details.

PA C K A G E O R D E R I N F O R M AT I O N

TA (°C)			Dropout		P	Plastic TO-220		DD	Plastic TO-263
			Voltage			3-pin			3-pin
0 to 125			1.3V			LX8587-xxCP		LX8587-xxCDD
			1.2V			LX8587A-xxCP		LX8587A-xxCDD

Note: All surface-mount packages are available in Tape & Reel. Append the letter "T" to part number. (i.e. LX8587A-00CDDT)

"xx" refers to output voltage, please see table above.

	Copyright © 1998	L I N F I N I T Y M I C R O E L E C T R O N I C S I N C .	1
		11861 WESTERN AVENUE, GARDEN GROVE, CA. 92841, 714-898-8121, FAX: [phone]
	Rev. 1.2 3/98

P R O D U C T D A T A B O O K 1 9 9 6 / 1 9 9 7

LX8587-xx/8587A-xx

3 A L O W D R O P O U T P O S I T I V E R E G U L AT O R S

P R O D U C T I O N D A T A S H E E T

	ABSOLUTE MAXIMUM RATINGS	(Note 1)
	Power Dissipation ................................................................................	Internally Limited
	Input Voltage ...............................................................................................................	10V
	Input to Output Voltage Differential ..........................................................................	10V
	Maximum Output Current .............................................................................................	5A
	Operating Junction Temperature
	Plastic (P Package) ...............................................................................................	150°C
	Storage Temperature Range ......................................................................	-65°C to 150°C
	Lead Temperature (Soldering, 10 seconds) ............................................................	300°C

Note 1. Exceeding these ratings could cause damage to the device. All voltages are with respect to Ground. Currents are positive into, negative out of the specified terminal.

THERMAL DATA

P PACKAGE:

THERMAL RESISTANCE-JUNCTION TO TAB, θJT	3.0°C/W
THERMAL RESISTANCE-JUNCTION TO AMBIENT, θJA	60°C/W
DD PACKAGE:
THERMAL RESISTANCE-JUNCTION TO TAB, θJT	3.0°C/W
THERMAL RESISTANCE-JUNCTION TO AMBIENT, θJA	60°C/W*

Junction Temperature Calculation: TJ = TA + (PD x θJA).

The θJA numbers are guidelines for the thermal performance of the device/pc-board system. All of the above assume no ambient airflow.

* With package soldered to 0.5 in.2 copper area over back-side ground plane or internal power plane, θJA can vary from 20°C/W to 40°C/W, depending on mounting technique.

PACKAGE PIN OUTS

TAB IS VOUT

3 VIN

2 VOUT

1 ADJ / GND*

P PACKAGE

(Top View)

* Pin 1 is GND for fixed voltage versions.

TAB IS VOUT

3			VIN
2			VOUT

1 ADJ / GND*

DDPACKAGE

(Top View)

* Pin 1 is GND for fixed voltage versions.

2		Copyright © 1998
		Rev. 1.2 3/98

P R O D U C T D A T A B O O K 1 9 9 6 / 1 9 9 7

LX8587-xx/8587A-xx

3 A L O W D R O P O U T P O S I T I V E R E G U L AT O R S

P R O D U C T I O N D A T A S H E E T

E L E C T R I C A L C H A R A C T E R I S T I C S

(Unless otherwise specified, these specifications apply over the operating ambient temperatures for the LX8587-xx/87A-xx with 0°C ≤ TA ≤ 125°C; VIN - VOUT = 3V; IOUT = 3A. Low duty cycle pulse testing techniques are used which maintains junction and case temperatures equal to the ambient temperature.)

LX8587-00/87A-00 (Adjustable)

	Parameter			Symbol	Test Conditions	LX8587/87A-00			Units
						Min.	Typ.	Max.
	Reference Voltage			VREF	IOUT = 10mA, TA = 25°C	1.238	1.250	1.262	V
					10mA ≤ IOUT ≤ 3A, 1.5V ≤ (VIN - VOUT), VIN ≤ 7V, P ≤ PMAX	1.225	1.250	1.275	V
	Line Regulation (Note 2)			VREF (VIN)	IOUT = 10mA, 1.5V ≤ (VIN - VOUT), VIN ≤ 7V		0.035	0.2	%
	Load Regulation	(Note 2)		VREF (IOUT)	VIN - VOUT = 3V, 10mA ≤ IOUT ≤ 3A		0.1	0.5	%
	Thermal Regulation			VOUT (Pwr)	TA = 25°C, 20ms pulse		0.01	0.02	%/W
	Ripple Rejection	(Note 3)			VOUT = 3.3V, f =120Hz, COUT = 100µf Tantalum, VIN = 5V	65	83		dB
					CADJ = 10µF, IOUT = 3A
	Adjust Pin Current			IADJ			55	100	µA
	Adjust Pin Current Change			IADJ	10mA ≤ IOUT ≤ 3A, 1.5V ≤ (VIN - VOUT), VIN ≤ 7V		0.2	5	µA
	Dropout Voltage		LX8587-00	V	VREF = 1%, IOUT = 3A		1.1	1.3	V
			LX8587A-00		VREF = 1%, IOUT = 3A		1	1.2	V
	Minimum Load Current			IOUT(MIN)	VIN ≤ 7V		2	10	mA
	Maximum Output Current			IOUT(MAX)	1.4V ≤ (VIN - VOUT), VIN ≤ 7V	3.0	5		A
	Temperature Stability			VOUT (T)			0.25		%
	Long Term Stability			VOUT (t)	TA = 125°C, 1000 hrs			1	%
	RMS Output Noise (% of VOUT)			VOUT (RMS)	TA = 25°C, 10Hz £ f £ 10kHz		0.003		%

LX8587-15/87A-15 (1.5V Fixed)

	Parameter			Symbol	Test Conditions	LX8587-15/87A-15			Units
						Min.	Typ.	Max.
	Output Voltage			VOUT	VIN = 5V, IOUT = 0mA, TA = 25°C	1.485	1.5	1.515	V
					3.0V ≤ VIN ≤ 7V, 0mA ≤ IOUT ≤ 3A, P ≤ PMAX	1.470	1.5	1.530	V
	Line Regulation (Note 2)			VOUT	4.75V ≤ VIN ≤ 7V		1	6	mV
				(VIN)	4.75V ≤ VIN ≤ 10V		2	10	mV
	Load Regulation (Note 2)			VOUT (IOUT)	VIN = 5V, 0mA ≤ IOUT ≤ IOUT (MAX)		5	7.5	mV
	Thermal Regulation (Note 3)			VOUT(Pwr)	TA = 25°C, 20ms pulse		0.01	0.02	% / W
	Ripple Rejection (Note 3)				COUT = 100µF (Tantalum), IOUT = 3A	60	75		dB
	Quiescent Current			IQ	0mA ≤ IOUT ≤ IOUT (MAX) , 4.75V ≤ VIN ≤ 10V		4	10	mA
	Dropout Voltage		LX8587-15	V	VOUT = 1%, IOUT ≤ IOUT (MAX)		1.1	1.3	V
			LX8587A-15		VOUT = 1%, IOUT ≤ IOUT (MAX)		1	1.2	V
	Maximum Output Current			IOUT (MAX)	VIN ≤ 7V	3.0	5.0		A
	Temperature Stability (Note 3)			VOUT (T)			0.25		%
	Long Term Stability	(Note 3)		VOUT (t)	TA = 125°C, 1000 hours		0.3	1	%
	RMS Output Noise (% of VOUT) (Note 3)			VOUT (RMS)	TA = 25°C, 10Hz ≤ f ≤ 10kHz		0.003		%

Note 2. Regulation is measured at constant junction temperature, using pulse testing with a low duty cycle. Changes in output voltage due to heating effects are covered under the specification for thermal regulation.

Note 3. These parameters, although guaranteed, are not tested in production.

Copyright © 1998	3
Rev. 1.2 3/98