Advanced Monolithic Systems AMS431L Service Manual

http://www.BDTIC.com/AMS

Advanced AMS431L

Monolithic 1.2V SHUNT REGULATOR
Systems

RoHS compliant

FEATURES APPLICATIONS

• Trimmed 0.5% Tolerance • Battery Powered Systems

• Wide Operating Current Range 60µA to 100mA • Switching Power Supplies

• Low Reference Input Current 0.4µA • Adjustable Power Supplies

• Low Dynamic Output Impedance • Telecommunications

• Low Output Noise • Error Amplifiers

• Nominal Temperature Range to 85°C • Notebook/Personal Computer

• Temperature-Compensated: 60ppm/°C • Monitors/ VCR/ TV

GENERAL DESCRIPTION

The AMS431L is a three-terminal adjustable shunt regulator with guaranteed temperature stability over the entire range of
operation. The output voltage can be set to any value between 1.24V (V
AMS431L features 0.5% initial tolerance, low dynamic output impedance and operates over a wide current range. Due to the
sharp turn-on characteristics this device is an excellent replacement for zener diodes in many applications.
AMS431 is available in TO-92, SOT-89, 3 pin SOT-23 and 5 pin SOT-23 packages.

ORDERING INFORMATION:

TOL. PACKAGE TYPE OPERATING

TO-92 SOT-89 3 LEAD SOT-23 5 LEAD SOT-23

±0.5%
±1.0%
±2.0%

AMS431LAN AMS431LAL AMS431LAM AMS431LAM1
AMS431LBN AMS431LBL AMS431LBM AMS431LBM1
AMS431LCN AMS431LCL AMS431LCM AMS431LCM1

PIN CONNECTIONS

TO-92 SOT-89 3L SOT-23 5L SOT-23

Plastic Package (N) (L) (M) (M1)

123

REF

ANODE

CATHODE

Bottom View Top View Top View Top View

123

CATHODEANODEREF

• Pagers

) and 20V by adding two external resistors. The

REF

TEMP. RANGE

-40 to +85° C

-40 to +85° C

-40 to +85° C

ANODE

CATHODEREF

N/C ANODE
N/C

CATHODE

1
2
3

5

4

REFERENCE

Advanced Monolithic Systems, Inc.

http://www.BDTIC.com/AMS

AMS431L

ABSOLUTE MAXIMUM RATINGS (Note 1)

Cathode Voltage (VZ) 20V Internal Power Dissipation (PD)
Continuous Cathode Current (I
Reference Input Current (I
Junction Temperature (T
SOT-23-5 Package 0.3 W
Storage temperature
Lead Temperature (Soldering, 25sec.)
SOT-89 Package
SOT-23-3 Package
SOT-23-5 Package

Note 1 : Absolute Maximum Ratings indicate limits beyond which dam a ge to the device may occur. Operating Ratings indicate conditions for which the

device is intended to be functional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see the Electrical
Characteristics

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

ELECTRICAL CHARACTERISTICS

Electrical Characteristics at IZ =10 mA and TA = +25°C unless otherwise noted.

Parameter

Conditions

) 100mA TO-92 Package 0.78W

Z

) 3mA SOT-89 Package 0.91W

REF

)

J

-40°C to +125°C

-65°C to +150°C
265°C

AMS431LA

Min Typ Max

SOT-23-3 Package 0.28W

Thermal Resistance (θ

)

JA

TO-92 Package

AMS431LB

Min Typ Max

AMS431LC

Min Typ Max

160°C/W
110°C/W
410°C/W
410°C/W

Units

Reference Voltage 1.234 1.240 1.246 1.228 1.240 1.252 1.215 1.240 1.265 V
Deviation of Reference

Input Voltage over
Temperature

Ratio of Change in
Reference Voltage to
Cathode Voltage

Reference Input
Current

Reference Input
Current Deviation over
Temperature

Off State Cathode
Current

Dynamic Output
Impedance

Minimum Operating
Current

= V

V
T

A

I

Z

∆V = from V

R1 =10kΩ, R2 = ∞Ω
(test circuit 2)

R1 =10kΩ, R2 = ∞Ω
T

A

(test circuit 2)
VZ = 6V, V

( test circuit 3)
f < 1KHz, VZ = V

IZ =100µA to 100mA
(test circuit 1)

VZ = V
(test circuit 1)

(circuit 1)

Z

REF

= -40°C to +85°C

= 10mA

REF

= Full Range

= 0V

REF

REF

REF

0.15 0.5 0.15 0.5 0.15 0.5

0.1 0.4 0.1 0.4 0.1 0.4

0.04 0.1 0.04 0.1 0.04 0.1

0.25 0.4 0.25 0.4 0.25 0.4

60 80 60 80 60 80

10

-0.5

25

-2.7 -0.5 -2.7 -0.5 -2.7 mV/V

10

25

10

35

mV

µA

µA

µA

Ω

µA

RECOMMENDED OPERATING CONDITIONS:

Min Max

Cathode Voltage, (VZ) V
Cathode Current, (IZ)

20 V

REF

80µA

100mA

Advanced Monolithic Systems, Inc.

http://www.BDTIC.com/AMS

AMS431L

TEST CIRCUITS

I

Z

VZ = V

REF

V

IN

R1

R2

V

IN

I

REF

V

REF

V

Z

I

REF

V

REF

I

Z

V

IN

Figure 1. Test Circuit for VZ=V

Figure 2. Test Circuit for V

REF

Test circuit for I

REF

REF

vs IZ.

.

Figure 3. Test Circuit for Off-State Current

TYPICAL APPLICATIONS

V

Z

IZ OFF

V

GND

IN

R1

V

REF

R2

V

OUT

1) Set the V

2) Choose the value of R as follows:

• The maximum limit for R should be such that the cathode current, I

• The minimum limit for R should b such that I

exceed 150mA. Both of the following conditions must be met:

according to the following equation:

OUT

R1

⎞

⎛

1V V REFREFOUT +

+=

⎜

R2

⎝

IN(max)

V

min Ion - turnousinstantanelimit to

R ≥

R Z

min

≥

()

150mA

OUTIN(max)

V-V

OUT(min)

100mAI

+

R1I

⎟
⎠

()

does not exceed 100mA under all load conditions, and the instantaneous turn-on value for IZ does not

Z

Z

conditions operating normalunder Ilimit to

is greater than the minimum operating current (80µA) at V

Z

IN(min)

.

Advanced Monolithic Systems, Inc.