CAT102 Precision, Adjustable Shunt Regulator (600mV Reference) - +1% Initial Accuracy - SOT23 Package FEATURES ■ Low voltage reference: 600mV ■ Low supply current: 300µA ■ Low temperature coefficient reference: 25ppm ■ Open collector output ■ Accurate 600mV reference voltage: ■ Directly drives optocouplers +6mV at TJ=25°C ■ Compact 5-lead SOT23 package ■ High PSRR: 45dB at 300kHz ■ Industrial temperature range: -40°°C to 85°°C ■ High line rejection: +1mV (VCC from 2.2V to 18V) APPLICATIONS ■ SMPS control loop ■ Isolated DC-to-DC converters ■ Low temperature coefficient voltage reference ■ Network, telecom and cellular base station power supplies ■ Power management ■ Adjustable voltage reference ■ Replaces zener diodes DESCRIPTION The CAT102 is a low-voltage reference and amplifier. Designed for the control loop of low-voltage power supplies, the reference voltage has been designed for 600mV. Over a junction temperature from -40°C to 105°C the reference voltage is within 8mV of the nominal 600mV. In addition, the error amplifier output and the supply voltage pin are on separate pins. Power supply rejection is a high 45dB at 300kHz. The output, OUT, can sink 20mA at a maximum saturation voltage of 250mV. FUNCTIONAL DIAGRAM PIN CONFIGURATION IN 5 FB 1 When combined with an optocoupler, the CAT102 can be used as an error amplifier that controls the feedback loop in isolated low-output voltage switching power supplies. OUT 3 SOT23-5 TOP VIEW Error Amplifier + VREF FB 1 – 5 IN GND 2 + – OUT 3 600mV 4 NC 2 GND © 2003 by Catalyst Semiconductor, Inc. Characteristics subject to change without notice 1 Doc. No. 4007, Rev. L CAT102 PIN DESCRIPTIONS Pin Number Pin Name Function 1 FB 2 GND Ground 3 OUT Output of error amplifier. Source & sink current capability is 20mA. 4 NC No connection 5 IN Positive supply Inverting input to error amplifier ORDERING INFORMATION Part Number Package Temperature Range CAT102EUK-TE7 5-Pin SOT-23 -40˚ C to 85˚ C TE7 = 7" Reel, 3,000 parts per reel. Doc. No. 4007, Rev. L 2 CAT102 ABSOLUTE MAXIMUM RATINGS These are stress ratings only and functional operation is not implied. Exposure to absolute maximum ratings for prolongued time periods may affect device reliability. All voltages are with respect to ground. VIN Voltage ........................................................... 20V OUT Voltage ........................................................ 20V FB Voltage ........................................................... 20V VIN, OUT, FB Current ........................................ 50mA Operating Junction Temperature ..................... 150°C Lead Soldering Temperature (10 sec) ............. 260°C Storage Temperature Range ........... -65°C to +150°C ELECTRICAL CHARACTERISTICS Electrical characteristics are guaranteed over the full operating temperature range of -40°C to +85°C with a junction temperature from -40°C to +105°C unless otherwise specified. Ambient temperature must be de-rated based upon power dissipation and package thermal characteristics.1 Unless otherwise stated, test conditions are VIN=3V, FB=OUT, IOUT=1mA. Symbol Parameter Min VIN Supply Voltage Range IIN Quiescent Supply Current VOUT=1V FB Threshold Reference Voltage TJ = 25˚ C 594 -40˚ C<TJ<105˚ C 588 VFB IFB PSRR Typ Max Units 18 V 0.3 0.5 mA 600 606 2.2 Line Regulation VIN = 2.2V to VIN=18V Load Regulation IOUT = 1mA to 10mA FB Input Current mV 612 0.5 1 mV 4 8 mV 500 nA -500 Reference Power Supply Rejection Frequency = 300kHz 35 45 dB AV Error Amplifier Open Loop Gain IOUT = 2mA, VOUT = 1V 60 80 dB BW Unity Gain Frequency IOUT = 2mA, VOUT = 1V 1 2 MHz VOUT Output Saturation voltage IOUT = 20mA, VFB = HIGH 100 IOUT = 1mA to 20mA 2.5 200 TRANSC Output Transconductance 1. Conditions ILEAK Output Leakage Current VOUT = 16V, VFB = 0 IOUT(MAX) Maximum Output Current VOUT = 0.3V 20 250 mV mA/mV 400 nA mA Thermal Characteristics (ΘJA) 5-lead, SOT-23: 255°C/W 3 Doc. No. 4007, Rev. L CAT102 TYPICAL PERFORMANCE CHARACTERISTICS Line Regulation (at 1mA) Load Regulation 6 Output Voltage Change (mV) Output Voltage Change (mV) 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 2.2 6 10 14 18 5 4 3 2 1 0 1 5 Supply Voltage (V) -55 260 -60 240 -65 PSRR (dB) Supply Current (µA) -50 280 220 200 180 -70 -75 -80 160 -85 140 -90 120 -95 100 -100 10 15 0.1 20 Load Current (mA) Doc. No. 4007, Rev. L 20 Power-Supply Rejection Ratio vs. Frequency 300 5 15 Load Current (mA) Supply Current vs. Load Current 0 10 1 10 100 1000 Frequency (Hz) 4 10000 100000 CAT102 TYPICAL PERFORMANCE CHARACTERISTICS FB Bias Current vs. Temperature (VCC=2.5V) Reference Voltage 630 -10 Reference Voltage (V) FB Bias Current (nA) 0 -20 -30 -40 -50 -60 -70 -40 0 40 80 10mA 620 610 600 590 580 570 120 -40 Junction Temperature (°°C) 0 40 80 120 Junction Temperature (°°C) Gain vs. Frequency 110 Gain (dB) 90 70 50 30 10 -10 0.01 0.1 1 10 100 1000 10000 Frequency (kHz) 5 Doc. No. 4007, Rev. L CAT102 APPLICATIONS INFORMATION The CAT102 adjustable shunt regulator features isolated supply inputs and outputs, ideal for isolated power-supply applications using an optocoupler in the feedback path. The CAT102 sinks 20mA with V OUT at 0.3V. The wide input supply range allows the device to operate from 2.2V to 18V. The CAT102 compares the FB input to a precision 600mv reference. If the FB input is low, the OUT pin sinks no current. If FB rises above 600mV, the OUT pin sinks up to 20mA. The current limit can be adjusted by using a resistor R3 connected between the IN and OUT pins. For example, a 3.3V supply VIN is associated with R3 = 135Ω, and a 10V supply works best with R3 = 470Ω. The CAT102 shunt regulator is limited to low-current applications with the OUT pin capable of sinking up to 20mA max. Figure 1 shows the CAT102 configured as a shunt regulator. To generate an output voltage of 0.6V, the FB pin has to be directly connected to the OUT pin. A 1.0µF capacitor from OUT to GND is recommended when the output voltage is 0.6V. A resistor-divider connected from OUT to GND is used to produce a higher output voltage as set by the following equation: VOUT = (1 + R1/R2) x 0.6V R3 VOUT 0.6V/20mA VIN 3.3V 5 IN OUT 3 CAT102 2 GND FB 1 R3 VOUT = (1+R1/R2) x 0.6V VIN 3.3V 1.2V/20mA 5 IN OUT 3 R1 10k CAT102 2 GND FB 1 R2 10k Figure 1. Application circuits for 0.6V output and 1.2V output voltages Doc. No. 4007, Rev. L 6 CAT102 TYPICAL APPLICATIONS VIN VOUT Regulator with Isolation 1V regulated output Opto-isolator VCC > 2.2V R3 100Ω 5 IN OUT R4 100kΩ 3 R1 22kΩ CAT102 2 GND FB 1 R2 33kΩ Figure 2. Opto-Feedback Application Circuit In order to allow proper operation of the optocoupler and the CAT102, the supply voltage VCC must be greater than 2.2V. 7 Doc. No. 4007, Rev. L CAT102 PACKAGE OUTLINES 5 LEAD SOT-23 1.900 0.950 PIN #4 2.800+0.200 1.650+0.050 -0.150 BOTTOM PACKAGE PIN #5 PIN #1 0.350+0.150 -0.000 2.900+0.100 0. R 0. .0 0.152+0.008 R0 .0 30 X) .1 (4 -0 0.100+0.050 DATUM "A" 0.575 NOTES: 1. ALL DIMENSIONS ARE IN MM. 2. PACKAGE OUTLINE DIMENSIONS INCLUSIVE OF METAL BURR. 3. PACKAGE OUTLINE EXCLUSIVE OF MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.076MM. 4. ALL PACKAGE SURFACE TO BE MIRROR FINISH. 5. MOLDING WITH DIE FACING UP, AND FORMING WITH DIE FACING DOWN. 6. FOOT LENGTH TO BE MEASURED AT THE INTERCEPT POINT OF EXTERNAL LEADS AND DATUM "A". 7. LEADFINISH PLATING: 0.00762MM - 0.0254MM. PACKAGE OUTLINE EXCLUSIVE OF LEADFINISH PLATING. Doc. No. 4007, Rev. L 8 0.200 070 - 0 .1 30 1.100+0.200 0 02 0. 7+ 19 1.200+0.250 1.600 +0.050 -0.150 TOP PACKAGE R 0.418+0.250 PIN #3 0.400+0.150 -0.050 Copyrights, Trademarks and Patents Trademarks and registered trademarks of Catalyst Semiconductor include each of the following: DPP ™ AE2 ™ Catalyst Semiconductor has been issued U.S. and foreign patents and has patent applications pending that protect its products. For a complete list of patents issued to Catalyst Semiconductor contact the Company’s corporate office at 408.542.1000. CATALYST SEMICONDUCTOR MAKES NO WARRANTY, REPRESENTATION OR GUARANTEE, EXPRESS OR IMPLIED, REGARDING THE SUITABILITY OF ITS PRODUCTS FOR ANY PARTICULAR PURPOSE, NOR THAT THE USE OF ITS PRODUCTS WILL NOT INFRINGE ITS INTELLECTUAL PROPERTY RIGHTS OR THE RIGHTS OF THIRD PARTIES WITH RESPECT TO ANY PARTICULAR USE OR APPLICATION AND SPECIFICALLY DISCLAIMS ANY AND ALL LIABILITY ARISING OUT OF ANY SUCH USE OR APPLICATION, INCLUDING BUT NOT LIMITED TO, CONSEQUENTIAL OR INCIDENTAL DAMAGES. Catalyst Semiconductor products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the Catalyst Semiconductor product could create a situation where personal injury or death may occur. Catalyst Semiconductor reserves the right to make changes to or discontinue any product or service described herein without notice. Products with data sheets labeled "Advance Information" or "Preliminary" and other products described herein may not be in production or offered for sale. Catalyst Semiconductor advises customers to obtain the current version of the relevant product information before placing orders. Circuit diagrams illustrate typical semiconductor applications and may not be complete. Catalyst Semiconductor, Inc. Corporate Headquarters 1250 Borregas Avenue Sunnyvale, CA 94089 Phone: 408.542.1000 Fax: 408.542.1200 www.catalyst-semiconductor.com Publication #: Revison: Issue date: Type: 4007 L 8/20/03 Final