Advanced Monolithic Systems AMS421 0.5V SHUNT REGULATOR RoHS compliant FEATURES APPLICATIONS • Trimmed 0.5% Tolerance • Wide Operating Current Range 0.1µA to 10mA • Low Reference Input Current 1.5nA • Low Dynamic Output Impedance • Low Output Noise • Nominal Temperature Range to 125°C • Temperature-Compensated: 50ppm/°C • Low supply current: typ. 10µA • Battery Powered Systems • Switching Power Supplies • Isolated Power Supplies • Telecommunications • Error Amplifiers • Notebook/Personal Computer • Monitors/ VCR/ TV • Opto-isolator 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 (VREF) and 15V by adding two external resistors. The AMS421 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. AMS421 is available 5 pin SOT-23 packages. ORDERING INFORMATION: TOL. Package 5 LEAD SOT-23 AMS421AM1 AMS421BM1 AMS421CM1 ±0.5% ±1.0% ±2.0% PIN CONNECTIONS OPERATING TEMP. RANGE -40 to + 125°C -40 to + 125°C -40 to + 125°C 5L SOT-23 (M1) VCC 1 5 COLL GND 2 BLOCK DIAGRAM N/C 3 4 REF VCC 1 Top View 5 Ref 4 Co + 0.5V 2 GND Advanced Monolithic Systems, Inc. www.advanced-monolithic.com Phone (925) 443-0722 Fax (925) 443-0723 AMS421 ABSOLUTE MAXIMUM RATINGS (Note 1) Supply Voltage (VCC) Continuous Collector Current (IC) Reference Input Current (IREF) Junction Temperature (TJ) 15V 10mA 0.5mA -40°C to +125°C Storage temperature Lead Temperature (Soldering, 10sec.) -65°C to +150°C 265°C Internal Power Dissipation (PD) SOT-23-5 Package 0.3 W Thermal Resistance (θJA) SOT-23-5 Package 410°C/W 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 ICOL =1 mA and TA = +25°C unless otherwise noted. Parameter Conditions Min Reference Voltage 497.5 AMS421A Typ Max 505.0 2.5 0.5 0.5 1.0 ICOL = 0.1µA to 10mA 0.5 Reference Input Current Deviation over Temperature ICOL = 0.1µA to 10mA Off State Collector Current Reference Input Current Dynamic Output Impedance Units mV 3 0.5 5 mV 0.5 1.5 0.5 2 mV 5 0..5 5 0.5 5 0.1 0.7 0.1 0.7 0.1 0.7 VREF = 0V 0.04 0.1 0.04 0.1 0.04 0.1 nA f < 1KHz, 0.35 0.5 0.35 0.5 0.35 0.5 Ω 0.1 nA 20 µA ICOL = 100µA 490.0 AMS421C Typ Max 510.0 Change in Reference Voltage to Supply Voltage 0.5 495.0 Min 500.0 VCOL = VREF TA = -40°C to +125°C 502.25 AMS421B Typ Max 500.0 Deviation of Reference Voltage over Temperature 500.0 Min Vcc=1.4V to 15V nA nA TA = Full Range ICOL =1 nA to 10mA Minimum Operating Current VCOL = VREF Input Supply Current ICOL = 100 µA 0.1 15 20 0.1 15 20 15 RECOMMENDED OPERATING CONDITIONS: Collector Voltage, (VCOL) Collector Current, (ICOL) Min VREF 1µA Advanced Monolithic Systems, Inc. Max 15 V 10mA www.advanced-monolithic.com Phone (925) 443-0722 Fax (925) 443-0723 AMS421 TYPICAL APPLICATIONS 1.5V ≤ VCC ≤ 15V 1.5V to 15V 0.1µF 10K 1 5 VO 1.000V Ref 4 + 0.47µF 100K 100K 0.5V 500 pF 2 LOW NOISE PRECISSION 1.000V REFERENCE 2.5V ≤ VCC ≤ 15V VO Q1 0.1µ R3 1 5 4 + R1 0.47µF - Co 0.5V R2 2 GND Low cost LDO using an External PNP Set the VOUT according to the following equation: R1 ⎞ ⎛ VOUT = VREF⎜1 + ⎟ + IREFR1 R2 ⎠ ⎝ Maximum output current is (PNP Hfe)10mA. The transistor current rating and package depends of the application dropout. The power dissipation for the PNP transistor is Iout (Vin-Vout). The package type should be selected according to the Power dissipation. Advanced Monolithic Systems, Inc. www.advanced-monolithic.com Phone (925) 443-0722 Fax (925) 443-0723 AMS421 TYPICAL PERFORMANCE CHARACTERISTICS Vout change Output resistance Vs load Output voltage vs. Supply voltage @ 100 µA 1 0.6 0.8 0.5 mV 0.6 0.4 Vout change 0.4 0.3 0.2 0.2 0 0.1 output res 0 -0.2 0 5 10 0 15 2 4 Supply Current vs Input Voltage @100uA load uA 20 IVcc uA 15 uA 25 10 5 0 10 8 10 Supply current vs load 30 0 6 Load step mA Vcc 20 30 200 180 160 140 120 100 80 60 40 20 0 1.00E-06 1.00E-05 1.00E-04 1.00E-03 1.00E-02 Volts Ivcc uA Load Very low current regulation Input output transfer characteristic 0.51 0.9 0.8 0.7 0.5 Vout 0.495 Volts ouptut Volts 0.505 0.6 0.5 Vout 0.4 0.3 0.2 0.49 1.00E- 1.00E- 1.00E- 1.00E- 1.00E- 1.00E- 1.00E09 08 07 06 05 04 03 0.1 0 0 Advanced Monolithic Systems, Inc. 1 2 3 4 5 Volts input load www.advanced-monolithic.com Phone (925) 443-0722 Fax (925) 443-0723 AMS421 TYPICAL PERFORMANCE CHARACTERISTICS (Continued) Output rejection Load 1k /10n PSRR -30 0 -35 -10 -40 -20 Vout -40 dB dB -45 -30 Vout -50 -55 -50 -60 -60 -65 -70 1.00E+03 -70 10 100 1000 10000 100000 1000000 1.00E+04 1.00E+05 1.00E+06 Hz Hz Input Bias Current 6 5 nA 4 3 Ibias 2 1 0 5 10 15 20 Volts 2 mA load Transient @ VCC=5V, Output Cap=10 nF 2 mA load Transient at VCC=15V, Output Cap=10nF Advanced Monolithic Systems, Inc. Fast Start up 0-2V with common supply www.advanced-monolithic.com Phone (925) 443-0722 Fax (925) 443-0723 AMS421 TYPICAL PERFORMANCE CHARACTERISTICS (Continued) Slow Start up 0-2V with common supply Advanced Monolithic Systems, Inc. www.advanced-monolithic.com Phone (925) 443-0722 Fax (925) 443-0723 AMS421 PACKAGE DIMENSIONS inches (millimeters) unless otherwise noted. 5 LEAD SOT-23 PLASTIC PACKAGE (M1) 0.110-0.120 (2.794-3.048) 0.102-0.118 (2.60-3.00) 0.059-0.070 (1.50-1.75) 0.014-0.020 (0.350-0.50) 0.037 (0.95) TYP 0.018-0.024 (0.457-0.610) 10° NOM 0.036-0.051 (0.090-1.30) 0.0035-0.0080 (0.090-0.20) 0.003 (0.150) MAX Advanced Monolithic Systems, Inc. 0.075 (1.90) TYP www.advanced-monolithic.com 10° NOM 0.018-0.024 (0.457-0.610) (SOT-23-5 ) AMS DRW# 051001 Phone (925) 443-0722 Fax (925) 443-0723