Fairchild Semiconductor RC1585X15 Datasheet

www.fairchildsemi.com

Pentium is a registered trademark of Intel Corporation. REV. 1.1.4 10/8/02

Features

• Fast transient response

• Low dropout voltage at up to 5A

• Load regulation: 0.05% typical

• Trimmed current limit

• On-chip thermal limiting

• Standard TO-220, TO-263, TO-263 center cut and TO-252
packages

Applications

• Pentium® class GTL+ bus supply

• Low voltage logic supply

• Post regulator for switching supply

Description

The RC1585 and RC1585-1.5 are low dropout three-terminal
regulators with 5A output current capability. These devices
have been optimized for low voltage applications including
V

TT

bus termination, where transient response and mini­mum input voltage are critical. The RC1585 is ideal for low
voltage microprocessor applications requiring a regulated
output from 1.5V to 3.6V with an input supply of 5V or less.
The RC1585-1.5 offers fixed 1.5V with 5A current capabili­ties for GTL+ bus V

TT

termination.

Current limit is trimmed to ensure specified output current
and controlled short-circuit current. On-chip thermal limit­ing provides protection against any combination of overload
and ambient temperature that would create excessive junc­tion temperatures.

The RC1585 series regulators are available in the industry­standard TO-220, TO-263, TO-263 center cut and TO-252
power packages.

Typical Applications

V

IN

= 3.3V

10µF

10µF

22µF

22µF

1.5V at 5A

124Ω

24.9Ω

+

+

V

IN

ADJ

V

OUT

RC1585

V

IN

= 3.3V

1.5V at 5A

+

+

V

IN

GND

V

OUT

RC1585-1.5

65-1585-01a

RC1585

5A Adjustable/Fixed Low Dropout Linear Regulator

RC1585 PRODUCT SPECIFICATION

2 REV. 1.1.4 10/8/02

Pin Assignments

Absolute Maximum Ratings

Parameter Min. Max. Unit

V

IN

7V

Operating Junction Temperature Range 0 125 °C

Storage Temperature Range -65 150 °C

Lead Temperature (Soldering, 10 sec.) 300 °C

ADJ

* θJA can vary from 20°C/W to >40°C/W with various mounting techniques.

OUT

FRONT VIEW

3-Lead Plastic TO-220

θJC = 3°C/W

INADJ

FRONT VIEW

3-Lead Plastic TO-263

θJC = 3°C/W*

IN

12 3

12 3

GND OUTOUT OUT

FRONT VIEW

IN

12 3

GND

FRONT VIEW

RC1585MRC1585M-1.5

RC1585T-1.5RC1585T

IN

12 3

ADJ

FRONT VIEW

3-Lead Plastic TO-263 Center Cut

θJC = 3°C/W*

IN

Tab is Out.

12 3

GND

FRONT VIEW

RC1585MCRC1585MC-1.5

IN

12 3

ADJ

FRONT VIEW

3-Lead Plastic TO-252

θJC = 3°C/W*

IN

Tab is Out.

12 3

GND

FRONT VIEW

RC1585DRC1585D-1.5

IN

12 3

65-1585-02

PRODUCT SPECIFICATION RC1585

REV. 1.1.4 10/8/02 3

Electrical Characteristics

Tj = 25°C unless otherwise specified.
The • denotes specifications which apply over the specified operating temperature range.

Notes:

1. See thermal regulation specifications for changes in output voltage due to heating effects. Load and line regulation are
measured at a constant junction temperature by low duty cycle pulse testing.

2. Line and load regulation are guaranteed up to the maximum power dissipation (18W). Power dissipation is determined by
input/output differential and the output currrent. Guaranteed maximum output power will not be available over the full input/
output voltage range.

3. RC1585 only.

4. RC1585-1.5 only.

Parameter Conditions Min. Typ. Max Units

Reference Voltage

3

1.5V ≤ (VIN – V

OUT

) ≤ 5.75V,

10mA ≤ I

OUT

≤ 5A

• 1.225
(-2%)

1.250 1.275
(+2%)

V

Output Voltage

4

3V ≤ VIN ≤ 7V
10mA ≤ I

OUT

≤ 5A

• 1.47 1.5 1.53 V

Line Regulation

1, 2

(V

OUT

+ 1.5V) ≤ VIN ≤ 7V,

I

OUT

= 10mA

• 0.005 0.2 %

Load Regulation

1, 2, 3

(VIN – V

OUT

) = 3V,

10mA ≤ I

OUT

≤ 5A

• 0.05 0.5 %

Dropout Voltage ∆V

REF

= 1%, I

OUT

= 5A • 1.150 1.300 V

Current Limit (VIN – V

OUT

) = 2V • 5.1 5.5 A

Adjust Pin Current

3

• 35 120 µA

Adjust Pin Current Change31.5V ≤ (VIN – V

OUT

) ≤ 5.75V,

10mA ≤ I

OUT

≤ 5A

• 0.2 5 µA

Minimum Load Current 1.5V ≤ (VIN – V

OUT

) ≤ 5.75V • 10 mA

Quiescent Current VIN = 5V • 413mA

Ripple Rejection f = 120Hz, C

OUT

= 22µF Tantalum,

(VIN – V

OUT

) = 3V, I

OUT

= 5A

60 72 dB

Thermal Regulation TA = 25°C, 30ms pulse 0.004 0.02 %/W

Temperature Stability • 0.5 %

Long-Term Stability TA = 125°C, 1000 hrs. 0.03 1.0 %

RMS Output Noise
(% of V

OUT

)

TA = 25°C, 10Hz ≤ f ≤ 10kHz 0.003 %

Thermal Resistance,
Junction to Case

TO-220 3 °C/W

TO-263, TO-252 3 °C/W

Thermal Shutdown 150 °C

RC1585 PRODUCT SPECIFICATION

4 REV. 1.1.4 10/8/02

Typical Performance Characteristics

Figure 1. Dropout Voltage vs. Output Current Figure 2. Load Regulation vs. Temperature

Figure 3. Reference Voltage vs. Temperature Figure 4. Output Voltage vs. Temperature

Figure 5. Minimum Load Current vs. Temperature Figure 6. Adjust Pin Current vs. Temperature

123

OUTPUT CURRENT (A)

DROPOUT VOLTAGE (V)

450

1.5

1.4

1.3

1.2

1.1

1.0

0.9

0.8

0.7

0.6

0.5

T=25°C

T=0°C

T=125°C

65-1585-03

JUNCTION TEMPERATURE (°C)

OUTPUT VOLTAGE DEVIATION (%)

-75 -50 -25 0 25 50 75 100 125 150 175

0.10

0.05

0

-0.05

-0.10

-0.15

-0.20

∆I = 5A

65-1585-04

JUNCTION TEMPERATURE (°C)

REFERENCE VOLTAGE (V)

-75 -50 -25 0 25 50 75 100 125 150 175

3.70

3.65

3.60

3.55

3.50

3.45

3.40

3.35

3.30

3.25

3.20

V

OUT

SET WITH 1% RESISTORS

V

OUT

= 3.6V

1

V

OUT

= 3.3V

1

Note:

1. RC1585 Only

65-1585-06

JUNCTION TEMPERATURE (°C)

REFERENCE VOLTAGE (V)

-75 -50 -25 0 25 50 75 100 125 150 175

1.275

1.270

1.265

1.260

1.255

1.250

1.245

1.240

1.235

1.230

1.225

65-1585-05

JUNCTION TEMPERATURE (°C)

MINIMUM LOAD CURRENT (mA)

-75 -50 -25 0 25 50 75 100 125 150 175

5

4

3

2

1

0

65-1585-07

JUNCTION TEMPERATURE (°C)

ADJUST PIN CURRENT (µA)

-75 -50 -25 0 25 50 75 100 125 150 175

100

90

80

70

60

50

40

30

20

10

0

65-1585-08

Note:

1. RC1585 Only