TS12001 A 0.65V/1µA Nanopower Voltage Detector with Dual Outputs FEATURES DESCRIPTION Nanopower Voltage Detector in Single 4 mm Package Ultra Low Total Supply Current: 1µA (max) Supply Voltage Operation: 0.65V to 2.5V Preset 0.78V UVLO Trip Threshold Internal ±10mV Hysteresis Resettable Latched Comparator Complimentary and Open-drain Comparator Outputs Separate Comparator Output Supply Pin 2 The TS12001 voltage detector combines a 0.58V reference and a comparator with resettable comparator latch in a single package. The TS12001 operates from a single 0.65V to 2.5V power supply and consumes less than 1µA total supply current. Optimized for ultra-long life operation, the TS12001 expands Touchstone’s growing “NanoWatt Analog™” high-performance analog integrated circuits portfolio. The voltage detector exhibits a preset UVLO threshold voltage of 0.78V (typ) or can be set to other threshold voltages with two external resistors. The comparator exhibits ±10mV of internal hysteresis for clean, chatter-free output switching. The TS12001 also offers both push-pull and open-drain outputs. When compared against similar products, the TS12001 offers a factor-of-2 lower power consumption and at least a 33% reduction in pcb area. APPLICATIONS Power-Fail Indicator Low-Battery Detection Battery-Backup Detection CPU, Microprocessor, and Logic Reset Controller Battery-powered Systems The TS12001 is fully specified over the -40°C to +85°C temperature range and is available in a lowprofile, 10-pin 2x2mm TDFN package with an exposed back-side paddle. TYPICAL APPLICATION CIRCUIT A Nanopower 1.8V Core System Voltage Detector The Touchstone Semiconductor logo and “NanoWatt Analog” are registered trademarks of Touchstone Semiconductor, Incorporated. Page 1 © 2012 Touchstone Semiconductor, Inc. All rights reserved. TS12001 ABSOLUTE MAXIMUM RATINGS Supply Voltage (VIN to VSS) ...................................................+2.75V Supply Voltage (OVDD to VSS) ................................................+2.75V Input Voltage SET………………...…………………...….VSS – 0.3V to VIN + 0.3V ET………………………………….…........VSS - 0.3V to +5.5V Output Voltage REFOUT……….…………………...…... VSS – 0.3V to VIN + 0.3V COUTPP……………..……….........… VSS - 0.3V to OVDD + 0.3V COUTOD……………………..…..………..… VSS - 0.3V to +5.5V Output Current COUTPP, COUTOD………...…………................................20mA Short-Circuit Duration (REFOUT, COUTPP, COUTOD)………...………...….Continuous Continuous Power Dissipation (TA = +70°C) 10-Pin TDFN (Derate at 13.48mW/°C above +70°C) ......... 1078mW Operating Temperature Range ................................ -40°C to +85°C Junction Temperature……………………………………..……+150°C Storage Temperature Range ................................. -65°C to +150°C Lead Temperature (Soldering, 10s) ..................................... +300°C Electrical and thermal stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only and functional operation of the device at these or any other condition beyond those indicated in the operational sections of the specifications is not implied. Exposure to any absolute maximum rating conditions for extended periods may affect device reliability and lifetime. PACKAGE/ORDERING INFORMATION ORDER NUMBER PART CARRIER QUANTITY MARKING TS12001ITD1022TP Tape & Reel ----- Tape & Reel 3000 AAN TS12001ITD1022T Lead-free Program: Touchstone Semiconductor supplies only lead-free packaging. Consult Touchstone Semiconductor for products specified with wider operating temperature ranges. Page 2 TS12001DS r1p0 RTFDS TS12001 ELECTRICAL CHARACTERISTICS VIN = OVDD = 0.8V; VSS = 0V; VSET = VSS; VCOUTPP = HiZ; VCOUTOD = HiZ; TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C. See note 1. PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Supply Voltage VIN 0.65 2.5 V TA = +25°C 0.8 Supply Current IIN REFOUT = open µA -40°C ≤ TA ≤ 85°C 1 UVLO Output Driver Supply OVDD 0.65 2.5 V Voltage Output Driver IODD 0.1 µA Supply Current V falling until COUTPP switches LOW 725 761 797 Preset UVLO IN mV Trip Point VIN rising until COUTPP switches HIGH 743 781 818 TA = +25°C 540 567 595 VSET falling until COUTPP switches LOW -40°C ≤ TA ≤ 85°C 534 604 SET Trip Point TA = +25°C 560 587 615 VSET rising until COUTPP switches HIGH -40°C ≤ TA ≤ 85°C 550 620 VSET rising 13 SET Trip µs Response Time VSET falling 10 Preset UVLO ±10 mV Trip Hysteresis SET Enable See Note 2 90 mV Threshold SET Input VSET = VSS; VSET = VIN 20 nA Leakage 0.78V ≤ VIN ≤ 1.1V 0.1 Comparator Latched Output ET Input VIL V Enabled Low Voltage 1.1V < VIN ≤ 2.5V 0.2 0.78V ≤ VIN ≤ 1.1V VIN -0.1 Comparator Latched Output ET Input VIH V Disabled High Voltage 1.1V < VIN ≤ 2.5V 1 ET Input V ET = VSS; V ET = 5.5V 100 nA Leakage TA = +25°C 555 577 600 Reference VREF mV Output Voltage -40°C ≤ TA ≤ 85°C 552 602 Reference Load IOUT = ±100nA 0.5 % Regulation Output High VOH COUTPP; IOUT = -100μA VIN – 0.1 V Voltage Output Low VOL COUTPP; IOUT = 100μA VSS + 0.1 V Voltage Output Low VOL COUTOD; IOUT = 100μA VSS + 0.11 V Voltage Sourcing; VCOUTPP = VSS 0.1 mA Output ShortCircuit ISC Sinking; VCOUTPP = VIN 0.5 mA Current, Sinking; VCOUTOD = VIN 1.4 mA Open Drain COUTOD; VCOUTOD = 5V 20 nA Leakage Note 1: All devices are 100% production tested at TA = +25°C and are guaranteed by characterization for TA = TMIN to TMAX, as specified. Note 2: A SET voltage above this threshold voltage enables the SET pin voltage to control the comparator output. TS12001DS r1p0 Page 3 RTFDS TS12001 PIN FUNCTIONS PIN NAME 1 VIN 2 SET 3 4 NC VSS 5 Page 4 ET 6 7 8 9 REFOUT NC COUTOD COUTPP 10 OVDD EP ---- FUNCTION Positive Supply Voltage. Connect a 0.1µF bypass capacitor from this pin to analog VSS/GND. External UVLO Trip Threshold Set Pin. When this pin is set to VSS, the internal preset 0.78V UVLO trip threshold controls the comparator output. When the applied voltage to this pin is higher than 90mV, the SET pin sets the trip threshold and controls the comparator output. If the SET pin is not used, connect the pin to to VSS. No Connection Negative Supply Voltage. Latch Enable Pin. When ET is set HIGH, the outputs of the comparator will toggle normally based on the inputs to the comparator. When ET is set LOW and COUTPP is HIGH, COUTPP will remain HIGH despite any changes to the input of the comparator. COUTPP will once again respond to changes to the input when ET is toggled HIGH. If COUTPP is initially LOW and the ET is then LOW, COUTPP will stay LOW. If a LOW-to-HIGH transition occurs on COUTPP, COUTPP will switch to HIGH and stay HIGH and not respond to any changes at the input. The ET pin must always be set to a known state. For unlatched comparator operation, set ET to HIGH. The open-drain output (COUTOD) is the inverted version of the COUTPP output. 0.58V Reference Output No Connection Comparator Open-Drain Output Comparator Push-Pull Output Output Driver Positive Supply Voltage. Connect a 0.1µF bypass capacitor from this pin to analog VSS/GND. Exposed paddle is electrically connected to VSS/GND. TS12001DS r1p0 RTFDS TS12001 BLOCK DIAGRAM THEORY OF OPERATION The TS12001 combines a 0.58V ±4.5% reference and an analog comparator with a resettable comparator latch in a single package. The TS12001 operates from a single 0.65V to 2.5V power supply and consumes less than 1µA total supply current. The TS12001 comparator has a push-pull and opendrain output driver. The push-pull output driver is powered from a separate supply voltage, OV DD. The open-drain output stage allows for easy output voltage level translation as may be required when driving systems powered with a different power supply rail. The analog comparator exhibits ±10mV of internal hysteresis for clean, chatter-free output switching. The internal reference was designed to sink or source up to 0.1µA load currents. The TS12001 has a preset UVLO threshold voltage of 0.78V (typ) or can be set to other threshold voltages with two external resistors where the divided TS12001DS r1p0 voltage is applied to the SET pin. When the SET pin voltage is grounded or it is less than approximately 90mV, the internal preset UVLO threshold circuit will control the comparator outputs. If the SET pin is above approximately 90mV, the external voltage divider circuit will control the comparator outputs. The 0.58V reference voltage is tied to the inverting input of the comparator and the output of a switch is connected to the non-inverting input of the comparator. The output of the switch is either the SET voltage or the internal UVLO threshold voltage, depending on whether the SET pin voltage is above or below approximately 90mV. If the switch output is above 0.58V, the push-pull output (COUTPP) will be HIGH and the open-drain output (COUTOD) will be LOW and vice versa. For proper operation, the supply voltage VIN must be applied before the output driver supply voltage (OVDD) is applied. The TS12001 has a latch enable pin ( ET) that Page 5 RTFDS TS12001 allows the output of the comparator to latch to a HIGH state under certain conditions. If ET is set HIGH, the COUTPP output will switch based on the input to the comparator. When ET is set LOW and COUTPP is HIGH, COUTPP will remain HIGH until ET goes LOW. When COUTPP is initially LOW instead, COUTPP will latch HIGH until a LOWto-HIGH transition occurs on the COUTPP output. In essence, the ET pin offers a LOW-to-HIGH detection. However, ET must not be left open. The open-drain output, COUTOD, is the inverter version of the COUTPP output. Connect ET to VIN for normal operation or to VSS for ET enable. If the SET pin is not used, it cannot be left unconnected and should be tied to VSS. Comparator The TS12001 has an internal comparator that can eliminate supply glitches that commonly occur when output transitions occur. In addition, the input exhibits ±10mV of internal hysteresis in order to insure clean output switching behavior. The outputs can swing to APPLICATIONS INFORMATION External Voltage Detector Design Depending on the battery voltage used and the voltage one wishes to detect, the TS12001 can be designed accordingly. As shown in Figure 1, R1 and R2 can be selected based on the desired voltage to detect. Table 1. provides R1 and R2 resistor combinations for detecting various VIN voltages. VIN Threshold R1(MΩ) R2(MΩ) Voltage(V) 0.9 2.2 4.02 1.07 3.32 4.02 1.28 4.75 4.02 1.52 6.49 4.02 1.85 8.66 4.02 Table 1. Resistor Combinations for Several VIN Threshold Voltages The design equation for this circuit is shown below. The SET pin voltage (VSET) that will cause a HIGH-to-LOW transition on the output is approximately 580mV. To design the circuit, R1 or R2 can be selected along with the desired battery voltage to detect. Page 6 within 100mV of the supply rails. The COUTPP output can source and sink 0.1mA and 0.5mA of current. The COUTD outputs can sink 1.4mA of current with VCOUTOD = 0.78V Internal Reference The TS12001’s on-board 0.58V ±4.5% reference voltage can source and sink 0.1µA and 0.1µA of current and can drive a capacitive load less than 50pF and greater than 50nF with a maximum capacitive load of 250nF. The higher the capacitive load, the lower the noise on the reference voltage and the longer the time needed for the reference voltage to respond and become available on the REFOUT pin. With a 250nF capacitive load, the response time is approximately 20ms. While also available as a separate pin as REFOUT, the reference is tied internally to the inverting input of the comparator. Then, the second resistor value can be evaluated using the voltage divider equation below. R1= VN x R VSET x R VSET A Nanopower 1.8V Core System Voltage Detector When power supply rails sag in any system, it is important to alert the CPU. A CPU can be used to detect when I/O or core system voltages sag below a prescribed threshold as shown Figure 2. In this circuit, a 1.8V core system voltage detector is designed around the TS12001 providing a low battery detect signal. R1 and R2 were selected to set a SET voltage at 582mV so that when VCORE drops below 1.77V, the TS12001 output transitions to LOW. It is recommended to use 1% resistors for optimal accuracy. The circuit consumes approximately 0.75µA of current when VCORE = 1.8V. PC Board Layout and Power-Supply Bypassing While power-supply bypass capacitors are not typically required, it is good engineering practice to use 0.1uF bypass capacitors close to the device’s power supply pins. When the power supply impedance is high, the power supply leads are long, or there is excessive noise on the power supply traces. To reduce stray capacitance, it is also good TS12001DS r1p0 RTFDS TS12001 engineering practice to make signal trace lengths as short as possible. Also recommended are a ground plane and surface mount resistors and capacitors. Input Noise Radiated noise is common in low power circuits that require high impedance circuits. To minimize this effect, all traces between any of the inputs and passive component networks should be made as short as possible. Figure 1. External Voltage Detector Design Circuit Figure 2. A Nanopower 1.8V Core System Voltage Detector Circuit TS12001DS r1p0 Page 7 RTFDS TS12001 PACKAGE OUTLINE DRAWING 10-Pin TDFN22 Package Outline Drawing (N.B., Drawings are not to scale) 0.900±0.050 Exp.DAP 2.000±0.050 PIN #1 IDENTIFICATION 0.300±0.050 0.400 Bsc Pin 1 DOT BY MARKING 10L STSLP (2x2mm) 1.400±0.050 Exp.DAP 2.000±0.050 0.200±0.050 TOP VIEW BOTTOM VIEW NOTE! · All dimensions in mm. · This part is compliant with JEDEC MO-229 spec A 0.152 Ref 0.000-0.050 A MAX. 0.600 NOM. 0.550 MIN. 0.500 SIDE VIEW Information furnished by Touchstone Semiconductor is believed to be accurate and reliable. However, Touchstone Semiconductor does not assume any responsibility for its use nor for any infringements of patents or other rights of third parties that may result from its use, and all information provided by Touchstone Semiconductor and its suppliers is provided on an AS IS basis, WITHOUT WARRANTY OF ANY KIND. Touchstone Semiconductor reserves the right to change product specifications and product descriptions at any time without any advance notice. No license is granted by implication or otherwise under any patent or patent rights of Touchstone Semiconductor. Touchstone Semiconductor assumes no liability for applications assistance or customer product design. Customers are responsible for their products and applications using Touchstone Semiconductor components. To minimize the risk associated with customer products and applications, customers should provide adequate design and operating safeguards. Trademarks and registered trademarks are the property of their respective owners. Touchstone Semiconductor, Inc. 630 Alder Drive, Milpitas, CA 95035 +1 (408) 215 - 1220 ▪ www.touchstonesemi.com Page 8 TS12001DS r1p0 RTFDS