Advanced Monolithic Systems

Transcription

1 Advanced Monolithic Systems AMS431L 1.2V SHUNT REGULATOR FEATURES Trimmed.5% Tolerance Wide Operating Current Range 6µA to ma Low Reference Input Current.4µA Low Dynamic Output Impedance Low Output Noise Nominal Temperature Range to 85 C Temperature-Compensated: 6ppm/ C APPLICATIONS Battery Powered Systems Switching Power Supplies Adjustable Power Supplies Telecommunications Error Amplifiers Notebook/Personal Computer Monitors/ VCR/ TV Pagers 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 REF ) and 2V by adding two external resistors. The AMS431L features.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 TEMP. RANGE ±.5% AMS431LAN AMS431LAL AMS431LAM AMS431LAM1-4 to +85 C ±1.% AMS431LBN AMS431LBL AMS431LBM AMS431LBM1-4 to +85 C ±2.% AMS431LCN AMS431LCL AMS431LCM AMS431LCM1-4 to +85 C PIN CONNECTIONS TO-92 SOT-89 3L SOT-23 5L SOT-23 Plastic Package (N) (L) (M) (M1) ANODE N/C 1 5 ANODE REF ANODE CATHODE REF ANODE CATHODE REF CATHODE N/C 2 CATHODE 3 4 REFERENCE Bottom View Top View Top View Top View

2 ABSOLUTE MAXIMUM RATINGS (Note 1) Cathode Voltage (V Z ) 2V Internal Power Dissipation (P D ) Continuous Cathode Current ( ) ma TO-92 Package.78W Reference Input Current (I REF ) 3mA SOT-89 Package.91W (T J ) -4 C to +125 C SOT-23-3 Package.28W SOT-23-5 Package.3 W Storage temperature -65 C to +15 C Thermal Resistance (θ JA ) Lead Temperature (Soldering, 1sec.) 265 C TO-92 Package 16 C/W SOT-89 Package 1C/W SOT-23-3 Package 4C/W SOT-23-5 Package 4C/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 =1 ma and T A = +25 C unless otherwise noted. Parameter Conditions AMS431LA Min Typ Max AMS431LB Min Typ Max AMS431LC Min Typ Max Units Reference Voltage 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 (circuit 1) T A = -4 C to +85 C = 1mA V = from V REF R1 =1kΩ, R2 = Ω (test circuit 2) R1 =1kΩ, R2 = Ω T A = Full Range (test circuit 2) V Z = 6V, V REF = V ( test circuit 3) f < 1KHz, =µa to ma (test circuit 1) (test circuit 1) mv mv/v µa µa µa Ω µa RECOMMENDED OPERATING CONDITIONS: Min Max Cathode Voltage, (V Z ) V REF 2 V Cathode Current, ( ) 8µA ma

3 TEST CIRCUITS V Z V Z I REF R1 I REF OFF V REF R2 V REF Figure 1. Test Circuit for V Z=V REF Figure 2. Test Circuit for V REF vs. Test circuit for I REF. Figure 3. Test Circuit for Off-State Current TYPICAL APPLICATIONS V OUT R1 V REF R2 GND 1) Set the V OUT according to the following equation: R1 VOUT = VREF IREFR1 R2 2) Choose the value of R as follows: The maximum limit for R should be such that the cathode current, is greater than the minimum operating current (8µA) at (min). The minimum limit for R should b such that does not exceed ma under all load conditions, and the instantaneous turn-on value for does not exceed 15mA. Both of the following conditions must be met: VIN(max) Rmin 15mA ( to limit instantaneous turn - on IZ) VIN(max) - VOUT Rmin IOUT(min) + ma ( to limit IZ under normal operating conditions )

4 TYPICAL PERFORMANCE CHARACTERISTICS CATHODE CURRENT (µa) Cathode Current vs. Cathode Voltage V R = V REF CATHODE CURRENT (ma) Cathode Current vs. Cathode Voltage V R = V REF REFERENCE VOLTAGE (V) Reference Voltage vs. = ma I R = 6µA CATHODE VOLTAGE (V) CATHODE VOLTAGE (V) REFERENCE INPUT CURRENT (na) Reference Input Current vs. = 1mA R 1 = 1kΩ R 2 = V REF / V Z (-mv/v) Ratio of Delta Reference Voltage to Delta Cathode Voltage vs. 1.2 = 1mA 1.1 V Z = 16V to V REF CATHODE CURRENT(OFF STATE) (na) Off State Cathode Current vs. V REF = V V R = 16V V Z = 6V REFERENCE IMPEDANCE (Ω) Reference Impedance vs. =.1 to ma f< 1kHz REFERENCE IMPEDANCE (Ω) Reference Impedance vs. Frequency FREQUENCY (khz)

5 TYPICAL PERFORMANCE CHARACTERISTICS (Continued) SMALL SIGNAL GAIN (db) Small Signal Gain and Phase Shift vs. Frequency k 1k k k FREQUENCY (Hz) PHASE SHIFT (deg) 1µF Small Signal Gain and Phase Shift Test Circuit 15k 8.25k OUT GND CATHODE CURRENT (ma) Stability Boundary Condition Stable Stable V Z = 2V LOAD CAPACITANCE ( µf) Stability Circuit R1 R2 C L

6 PACKAGE DIMENSIONS inches (millimeters) unless otherwise noted. 3L TO-92 PLASTIC PACKAGE (N).6±.5 (1.524±.127) DIA.18±.5 (4.572±.127).18±.5 (4.572±.127).9 (2.286).6±.1 (1.524±.254).14±.1 (3.556±.127).5 (12.7) MIN.5 (1.27) MAX UNCONTROLLED LEAD DIMENSIONS 5.5±.5 (1.27±.127).16±.3 (.46±.76).15±.2 (.381±.51) N (TO-92 ) AMS DRW# LEAD SOT-23 PLASTIC PACKAGE (M1) ( ) (2.6-3.) ( ).37 (.95) TYP (.35-.5) ( ) (.9-1.3) (.9-.2).3 (.15) MAX.75 (1.9) TYP ( ) (SOT-23-5 ) AMS DRW# 51

7 PACKAGE DIMENSIONS inches (millimeters) unless otherwise noted (Continued). 3 LEAD SOT-23 PLASTIC PACKAGE (M) ( ) ( ) ( ) ( ) ( ) ( ) ( ).5-.4 ( ).7-.8 ( ) ( ) ( ) (SOT-23 ) AMS DRW# SOT-89 PLASTIC PACKAGE (L) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ).59 (1.5) BSC ( ) ( ) L (SOT-89 ) AMS DRW# (3.) BSC