CAT102 Precision, Adjustable Shunt Regulator (600mV Reference) FEATURES DESCRIPTION Low voltage reference: 600mV 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. Low temperature coefficient reference: 25ppm Accurate 600mV reference voltage: +6mV at TJ = 25ºC High PSRR: 45dB at 300kHz High line rejection: ±1mV (VCC from 2.2V to 18V) Low supply current: 300µA Power supply rejection is a high 45dB at 300kHz. The output, OUT, can sink 20mA at a maximum saturation voltage of 250mV. Open collector output Directly drives optocouplers Compact 5-lead SOT23 package 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. Industrial temperature range: -40ºC to 85ºC APPLICATION SMPS control loop Low temperature coefficient voltage reference Power management For Ordering Information details, see page 8. Replaces zener diodes Isolated DC-to-DC converters Network, telecom and cellular base station Adjustable voltage reference PIN CONFIGURATION FUNCTIONAL DIAGRAM IN FB 1 5 Error Amplifier SOT-23 5L Top View OUT 3 + VREF 600mV – + – 1 1 GND 2 2 OUT 4 3 5 8 IN 4 5 NC PIN DESCRIPTION Pin Name 2 GND © 2007 Catalyst Semiconductor, Inc. Characteristics subject to change without notice FB FB 1 Function Inverting input to error amplifier GND Ground OUT Output of error amplifier. Source & sink current capability is 20mA. NC No connection IN Positive supply Doc. No. 4007 Rev. M CAT102 ABSOLUTE MAXIMUM RATINGS(1) Parameters Ratings Units VIN Voltage 20 V OUT Voltage 20 V FB Voltage 20 V VIN, OUT, FB Current 50 mA Operating Junction Temperature (10s) 150 ºC Lead Soldering Temperature (10s) 260 ºC -65 to +150 ºC Storage Temperature Range 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 VIN Supply Voltage Range IIN Quiescent Supply Current VFB FB Threshold Reference Voltage TCREF IFB PSRR Conditions Min Typ Max Units 18 V 0.3 0.5 mA 600 606 2.2 VOUT =1V TJ = 25˚ C 594 -40ºC <TJ<105ºC 592 Line Regulation VIN = 2.2V to VIN =18V Load Regulation Reference Temperature Deviation 608 mV 0.5 1 mV IOUT = 1mA to 10mA 4 8 mV -40ºC < TJ < 105ºC 25 50 ppm/ºC 500 nA FB Input Current -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 TRANSC Output Transconductance IOUT = 1mA to 20mA 2.5 ILEAK Output Leakage Current VOUT = 16V, VFB = 0 200 IOUT(MAX) Maximum Output Current VOUT = 0.3V 20 250 mV mA/mV 400 nA mA Notes: (1) 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. (2) Thermal Characteristics (ΘJA) of SOT-23 5-lead: 255°C/W Doc. No. 4007 Rev. M 2 © 2007 Catalyst Semiconductor, Inc. Characteristics subject to change without notice 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 5 4 3 2 1 0 18 1 5 Supply Voltage (V) 15 20 Power-Supply Rejection Ratio vs. Frequency Supply Current vs. Load Current 300 -50 280 -55 260 -60 240 -65 PSRR (dB) Supply Current (µA) 10 Load Current (mA) 220 200 180 -70 -75 -80 160 -85 140 -90 -95 120 -100 0.1 100 0 5 10 15 L o a d C u r re n t (m A ) © 2007 Catalyst Semiconductor, Inc. Characteristics subject to change without notice 20 1 10 100 1000 10000 100000 F re q u e n c y (H z ) 3 Doc. No. 4007 Rev. M CAT102 TYPICAL PERFORMANCE CHARACTERISTICS FB Bias Current vs. Temperature (V CC = 2.5V) Reference Voltage 630 -10 Reference Voltage (V) FB Bias Current (nA) 0 -20 -30 -40 -50 -60 620 10mA 610 600 590 580 -70 -40 0 40 80 570 -40 120 Junction Temperature (ºC) 0 40 80 120 Junction Temperature (ºC) Gain vs. Frequency 110 Gain (dB) 90 70 50 30 10 -10 0.01 0.1 1 10 100 1000 10000 Frequency (kHz) Doc. No. 4007 Rev. M 4 © 2007 Catalyst Semiconductor, Inc. Characteristics subject to change without notice 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 VOUT 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 resistordivider 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 Figure 1. Application circuits for 0.6V output and 1.2V output voltages R3 VIN VOUT 3.3V 0.6V/20mA 5 OUT IN 3 C2 C1 0.1µF CAT102 2 GND FB 1µF 1 R3 VIN VOUT = (1 + R1/R2) x 0.6V 3.3V 1.2V/20mA 5 OUT IN 3 C1 0.1µF CAT102 2 GND FB 1 R1 C2 10kΩ 1µF R2 10kΩ © 2007 Catalyst Semiconductor, Inc. Characteristics subject to change without notice 5 Doc. No. 4007 Rev. M CAT102 TYPICAL APPLICATION VIN VOUT Regulator with Isolation 1V regulated output Opto-isolator VCC > 2.2V R3 100Ω 5 OUT IN 3 C1 0.1µF R4 100kΩ R1 22kΩ C2 CAT102 2 GND FB 1 1µF 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. Doc. No. 4007 Rev. M 6 © 2007 Catalyst Semiconductor, Inc. Characteristics subject to change without notice CAT102 PACKAGE OUTLINES SOT-23 5 LEAD SYMBOL MIN NOM 1.15 A 1.00 A1 0.05 A2 1.00 b 0.35 C 1.10 1.20 0.50 D 2.80 2.90 3.00 E 2.60 2.80 3.00 E1 1.50 1.60 1.70 L 0.95 TYP 0.35 0.45 L1 0.60 REF L2 0.20 BSC θ SIDE VIEW 1.30 0.15 0.127 e TOP VIEW MAX 0° 0.55 8° θ1 10° θ2 10° END VIEW For current Tape and Reel information, download the PDF file from: http://www.catsemi.com/documents/tapeandreel.pdf. Notes: (1) All dimensions in millimeters. Angles in degrees. (2) Complies with ANSI Y14.5M. © 2007 Catalyst Semiconductor, Inc. Characteristics subject to change without notice 7 Doc. No. 4007 Rev. M CAT102 EXAMPLE OF ORDERING INFORMATION Prefix Device # Suffix CAT 102 Company ID TB I - Package TB: SOT-23 Product Number 102 Temperature Range I = Industrial (-40°C to 85°C) T3 Tape & Reel T: Tape & Reel 3: 3000/Reel 10: 10000/Reel Notes: (1) (2) All packages are RoHS-compliant (Lead-free, Halogen-free) The device used in the above example is a CAT102TBI-T3 (SOT-23, Industrial Temperature, Matte-Tin, Tape & Reel) ORDERING PART NUMBER CAT102TBI Doc. No. 4007 Rev. M 8 © 2007 Catalyst Semiconductor, Inc. Characteristics subject to change without notice REVISION HISTORY Date Rev. 01/29/2007 M Reason Added Ordering Information Copyrights, Trademarks and Patents Trademarks and registered trademarks of Catalyst Semiconductor include ech of the following: Beyond Memory™, DPP™, EZDim™, MiniPot™, and Quad-Mode™ Catalyst Semiconductor has been issued U.S. and foreign patents and has patent applications pending that protect its products. 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 2975 Stender Way Santa Clara, CA 95054 Phone: 408.542.1000 Fax: 408.542.1200 1Hwww.catsemi.com Document No: 4007 Revision: M Issue date: 01/29/07