Advanced Monolithic Systems AMS1085 Service Manual

http://www.BDTIC.com/AMS

Advanced AMS1085
Monolithic 3A LOW DROPOUT VOLTAGE REGULATOR

Systems
RoHS compliant

FEATURES APPLICATIONS

•••• Three Terminal Adjustable or Fixed Voltages •••• High Efficiency Linear Regulators

1.5V, 2.5V, 2.85V, 3.0V, 3.3V, 3.5V and 5.0V

•••• Output Current of 3A •••• Microprocessor Supply

•••• Operates Down to 1V Dropout •••• Battery Chargers

•••• Load Regulation: 0.1% •••• Constant Current Regulators

•••• Line Regulation: 0.015% •••• Notebook/Personal Computer Supplies

•••• TO-220, TO-263 and TO-252 packages available •••• Portable Instrumentation

GENERAL DESCRIPTION

The AMS1085 series of adjustable and fixed voltage regulators are designed to provide 3A output current and to operate down
to 1V input-to-output differential. The dropout voltage of the device is guaranteed maximum 1.3V at maximum output current,
decreasing at lower load currents.
On-chip trimming adjusts the reference voltage to 1%. Current limit is also trimmed, minimizing the stress under overload
conditions on both the regulator and power source circuitry.
The AMS1085 devices are pin compatible with older three-terminal regulators and are offered in 3 lead TO-220 package, 3 and
2 lead TO-263 (Plastic DD) and TO-252 (D PAK) package.

ORDERING INFORMATION:

3 LEAD TO-220 2&3 LEAD TO-263 TO-252

AMS1085CT AMS1085CM AMS1085CD
AMS1085CT-1.5 AMS1085CM-1.5 AMS1085CD-1.5
AMS1085CT-2.5 AMS1085CM-2.5 AMS1085CD-2.5
AMS1085CT-2.85 AMS1085CM-2.85 AMS1085CD-2.85
AMS1085CT-3.0 AMS1085CM-3.0 AMS1085CD-3.0
AMS1085CT-3.3 AMS1085CM-3.3 AMS1085CD-3.3
AMS1085CT-3.5 AMS1085CM-3.5 AMS1085CD-3.5
AMS1085CT-5.0 AMS1085CM-5.0 AMS1085CD-5.0

PIN CONNECTIONS

FIXED VERSION

1- Ground
2- V
3-

OUT

VIN

PACKAGE TYPE OPERATING JUNCTION

ADJUSTABLE VERSION

1- Adjust
2- V

OUT

3- VIN

••••

Post Regulators for Switching Supplies

TEMPERATURE RANGE

0 to 125° C
0 to 125° C
0 to 125° C
0 to 125° C
0 to 125° C
0 to 125° C
0 to 125° C
0 to 125° C

TO-220 FRONT VIEW

TO-252 FRONT VIEW

3

2

1

3

2

1

TAB IS

OUTPUT

2L TO-263 FRONT VIEW

TAB IS

OUTPUT

3
2
1

OUTPUT

TAB IS

3L TO-263 FRONT VIEW

3

2

1

TAB IS

OUTPUT

Advanced Monolithic Systems, Inc.

http://www.BDTIC.com/AMS

ABSOLUTE MAXIMUM RATINGS (Note 1)

Power Dissipation Internally limited Soldering information
Input Voltage 15V Lead Temperature (25 sec)
Operating
Control Section
Power Transistor
Storage temperature

Junction Temperature R

0°C to 125°C

0°C to 150°C

- 65°C to +150°C

Thermal Resistance

TO-220 package
TO-263 package
TO-252 package

* With package soldering to 0.5in
ground plane or internal power plane ϕ
20°C/W to >40°C/W depending on mounting technique.

2

copper area over backside

ELECTRICAL CHARACTERISTICS

Electrical Characteristics at I

= 0 mA, and TJ = +25°C unless otherwise specified.

OUT

AMS1085

265°C

ϕ JA= 50°C/W

ϕ JA= 30°C/W *

ϕ JA= 100°C/W

can vary from

JA

Parameter

Device Conditions Min Typ Max Units

Reference Voltage
(Note 2)

Output Voltage
(Note 2)

AMS1085-2.5

Line Regulation AMS1085/-1.5/-2.5/-

Load Regulation

(Notes 2, 3)

AMS1085-1.5

AMS1085-2.5

AMS1085-2.85

AMS1085-3.0

AMS1085-3.3

AMS1085-3.5

AMS1085-5.0

AMS1085 I

AMS1085-1.5

AMS1085-2.85

AMS1085-3.0

AMS1085-3.3

AMS1085-3.5

AMS1085-5.0

2.85/ -3.0/-3.3/-3.5/-5.0

AMS1085

= 10 mA

OUT

10mA ≤ I

0 ≤ I

0 ≤ I

0 ≤ I

0 ≤ I

0 ≤ I

0 ≤ I

0 ≤ I

I

LOAD

(VIN - V

VIN = 5V, 0 ≤ I

VIN = 5V, 0 ≤ I

VIN = 5V, 0 ≤ I

VIN = 5V, 0 ≤ I

VIN = 5V, 0 ≤ I

VIN = 5.25V, 0 ≤ I

VIN = 8V, 0 ≤ I

≤ 3A, 1.5V≤ (VIN - V

OUT

≤ 3A , 3V≤ VIN ≤ 12V

OUT

≤ 3A , 4V≤ VIN ≤ 12V

OUT

≤ 3A , 4.35V≤ VIN ≤ 12V

OUT

≤ 3A , 4.5V ≤ VIN ≤ 12V

OUT

≤ 3A , 4.75V ≤ VIN ≤ 12V

OUT

≤ 3A , 5V ≤ VIN ≤ 12V

OUT

≤ 3A , 6.5V ≤ VIN ≤ 12V

OUT

= 10 mA , 1.5V≤ (VIN - V

) =3V, 10mA ≤ I

OUT

OUT

OUT

OUT

OUT

OUT

OUT

≤ 3A

≤ 3A

≤ 3A

≤ 3A

≤ 3A

≤ 3A

OUT

≤ 3A

OUT

OUT

OUT

≤ 3A

) ≤ 12V

) ≤ 12V

1.238

1.225

1.485

1.470

2.475

2.450

2.82

2.79

2.970

2.940

3.267

3.235

3.465

3.430

4.950

4.900

0.3

3

3

3

3

3

3

5

1.250

1.250

1.500

1.500

2.500

2.500

2.850

2.850

3.000

3.000

3.300

3.300

3.500

3.500

5.000

5.000

0.6

0.1

0.2

6

6

6

6

7

6

10

1.262

1.270

1.515

1.530

2.525

2.550

2.88

2.91

3.300

3.360

3.333

3.365

3.535

3.570

5.050

5.100

10
10

0.3

0.4

12
20

12
20

12
20

12
20

15
25

15
25

20
35

V
V

V
V

V
V

V

V
V

V
V

V
V

V
V

mV
mV

%
%

mV
mV

mV
mV

mV
mV

mV
mV

mV
mV

mV
mV

mV
mV

Dropout Voltage

(V

- V

OUT

)

IN

AMS1085/-1.5/-2.5/-

2.85/ -3.0/-3.3/-3.5/-5.0

Advanced Monolithic Systems, Inc.

∆V

OUT

, ∆V

REF

= 1%, I

= 3 A (Note 4)

OUT

1.2 1.3

V

http://www.BDTIC.com/AMS

ELECTRICAL CHARACTERISTICS

Electrical Characteristics at I

= 0 mA, and TJ = +25°C unless otherwise specified.

OUT

AMS1085

Parameter

Device Conditions Min Typ Max Units

Current Limit

Minimum Load
Current

Quiescent Current AMS1085/-1.5/-2.5/-

Ripple Rejection AMS1085

AMS1085-1.5

AMS1085-2.5

AMS1085-2.85

AMS1085-3.0

AMS1085-3.3

AMS1085-3.5

AMS1085-5.0

Thermal Regulation AMS1085 TA = 25°C, 30ms pulse 0.008 0.04 %W

AMS1085/-1.5/-2.5/-

2.85/ -3.0/-3.3/-3.5/-5.0

(VIN - V

AMS1085 (VIN - V

VIN ≤ 12V

2.85/ -3.0/-3.3/-3.5/-5.0

f =120Hz , C
(VIN-V

f =120Hz , C
VIN = 4.5V

f =120Hz , C
VIN = 5.5V

f =120Hz , C
VIN = 6V

f =120Hz , C
VIN = 6V

f =120Hz , C
VIN = 6.3V

f =120Hz , C
VIN = 6.5V

f =120Hz , C
VIN = 8V

) = 5V

OUT

) = 12V (Note 5)

OUT

OUT

= 25µF Tantalum, I

OUT

) = 3V, C

ADJ

= 25µF Tantalum, I

OUT

= 25µF Tantalum, I

OUT

= 25µF Tantalum, I

OUT

= 25µF Tantalum, I

OUT

= 25µF Tantalum, I

OUT

= 25µF Tantalum, I

OUT

= 25µF Tantalum, I

OUT

=25µF

OUT

OUT

OUT

OUT

OUT

OUT

OUT

OUT

= 3A,

= 3A,

= 3A,

= 3A,

= 3A

= 3A

= 3A

= 3A

3.00 3.50 4.00

5 10

60 75

60

60

60

60 72

60 72

60 72

60 68

72

72

72

5

10

dB

A

mA

mA

dB

dB

dB

dB

dB

dB

dB

Adjust Pin Current AMS1085

Adjust Pin Current

AMS1085

Change

Temperature Stability

10mA ≤ I

10mA ≤ I

≤ 3A , 1.5V≤ (VIN - V

OUT

≤ 3A , 1.5V≤ (VIN - V

OUT

OUT

OUT

) ≤ 12V

) ≤12V

55

0.2

0.5

120

5

µA
µA

µA

%

Long Term Stability TA =125°C, 1000Hrs 0.3 1 %

RMS Output Noise

(% of V

OUT

)

Thermal Resistance
Junction-to-Case

TA = 25°C , 10Hz ≤ f ≤ 10kHz

M Package: Control Circuitry/ Power Transistor

T Package: Control Circuitry/ Power Transistor

0.003

1.5/4.0

1.5/4.0

°C/W
°C/W

%

Parameters identified with boldface type apply over the full operating temperature range.

Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. For guaranteed specifications and test conditions, see the

Electrical Characteristics. The guaranteed specifications apply only for the test conditions listed.

Note 2: Line and Load regulation are guaranteed up to the maximum power dissipation of 15W. Power dissipation is determined by the input/output

differential and the output current. Guaranteed maximum power dissipation will not be available over the full input/output range.

Note 3: See thermal regulation specifications for changes in output voltage due to heating effects. Line and load regulation are measured at a constant

junction temperature by low duty cycle pulse testing. Load regulation is measured at the output lead ~1/8” from the package.

Note 4: Dropout voltage is specified over the full output current range of the device.
Note 5: Minimum load current is defined as the minimum output current required to

to regulate if the output current is greater than 10mA.

maintain regulation. When (VIN - V

) = 12V the device is guaranteed

OUT

Advanced Monolithic Systems, Inc.