AMS421中文资料

Advanced AMS421 Monolithic 0.5V SHUNT REGULATOR Systems

RoHS compliant

FEATURES APPLICATIONS

? Trimmed 0.25% Tolerance ? Battery Powered Systems ? Wide Operating Current Range 0.1μA to 10mA ? Switching Power Supplies ? Low Reference Input Current 1.5nA ? Isolated Power Supplies ? Low Dynamic Output Impedance ? Telecommunications ? Low Output Noise ? Error Amplifiers ? Nominal Temperature Range to 125°C ? Notebook/Personal Computer ? Temperature-Compensated: 50ppm/°C ? Monitors/ VCR/ TV ? Low supply current: typ. 10μA ? Optoisolator driver

GENERAL DESCRIPTION

The AMS421 is a four-terminal adjustable open collector shunt regulator with guaranteed temperature stability over the entire range of operation. The output voltage can be set to any value between 0.5V (V REF ) and 15V by adding two external resistors. The AMS421 features 0.25% 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. AMS421 is available 5 pin SOT-23 packages.

ORDERING INFORMATION: PIN CONNECTIONS

TOL. Package 5 LEAD SOT-23

OPERATING

TEMP. RANGE ±0.25% AMS421AM1 -40 to + 125°C ±0.5%

AMS421BM1

-40 to + 125°C ±1.0%

AMS421CM1 -40 to + 125°C BLOCK DIAGRAM

5L SOT-23 (M1)

COLL REF

Top View

V CC

1

2Ref 4

5

+

-0.5V

Co

AMS421 ABSOLUTE MAXIMUM RATINGS (Note 1)

Supply Voltage (V CC) 15V Internal Power Dissipation (P D)

Continuous Collector Current (I C) 10mA SOT-23-5 Package 0.3 W Reference Input Current (I REF) 0.5mA

Junction Temperature (T J) -40°C to +125°C Thermal Resistance (θJA)

Storage temperature -65°C to +150°C SOT-23-5 Package 410°C/W Lead Temperature (Soldering, 10sec.) 265°C

Note 1 :Absolute Maximum Ratings indicate limits beyond which damage 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 I COL =1 mA and T A = +25°C unless otherwise noted.

Parameter Conditions

AMS421A

Min Typ Max

AMS421B

Min Typ Max

AMS421C

Min Typ Max Units

Reference Voltage 498.75 500.00 501.25 497.50 500.00 502.25 495.00 500.00 505.00 mV

Deviation of Reference Voltage over Temperature V COL = V REF

T A = -40°C to

+125°C

0.5 2.5 0.5 3 0.5 5 mV

Change in Reference Voltage to Supply Voltage I COL = 100μA

Vcc=1.4V to 15V

0.5 1.0 0.5 1.5 0.5 2 mV

Reference Input Current I COL = 0.1μA to

10mA

0.5 5 0..5 5 0.5 5

nA

Reference Input Current Deviation over Temperature I COL = 0.1μA to

10mA

T A = Full Range

0.1 0.7 0.1 0.7 0.1 0.7

nA

Off State Collector

Current

V REF = 0V 0.04 0.1 0.04 0.1 0.04 0.1 nA

Dynamic Output Impedance f < 1KHz,

I COL =1 nA to 10mA

0.35 0.5 0.35 0.5 0.35 0.5 ?

Minimum Operating

Current

V COL = V REF 0.1 0.1 0.1 nA Input Supply Current I COL = 100 μA 15 20 15 20 15 20 μA RECOMMENDED OPERATING CONDITIONS:

Min

Max

Collector Voltage, (V COL)V REF15 V

Collector Current, (I COL)1μA 10mA

AMS421

TYPICAL APPLICATIONS

LOW NOISE PRECISSION 1.000V REFERENCE

Set the V OUT according to the following equation:

2.5V ≤ V CC ≤ 15V

O

GND

R1

I R2R11V V REF REF OUT +?????

?

+

=1.5V ≤ V CC ≤ 15V

1.5V to 15V

V O

AMS421 TYPICAL PERFORMANCE CHARACTERISTICS

AMS421 TYPICAL PERFORMANCE CHARACTERISTICS (Continued)

2 mA load Transient @ VCC=5V, Output Cap=10 nF

2 mA load Transient at VCC=15V, Output Cap=10nF Fast Start up 0-2V with common supply

AMS421 TYPICAL PERFORMANCE CHARACTERISTICS (Continued)

Slow Start up 0-2V with common supply

AMS421 PACKAGE DIMENSIONS inches (millimeters) unless otherwise noted.

5 LEAD SOT-23 PLASTIC PACKAGE (M1)