TS12011/TS12012 A 0.8V/1.5µA Nanopower Op Amp, Comparator, and Reference FEATURES DESCRIPTION Nanopower Op Amp, Comparator, and 0.58V 2 Reference in Single 4 mm Package Ultra Low Total Supply Current: 1.6µA (max) Supply Voltage Operation: 0.8V to 2.5V Internal 0.58V Reference Op Amp and Comparator Input Ranges are Rail-to-Rail Unity-gain Stable Op Amp with AVOL = 104dB Op Amp Output: Rail-to-Rail and PhaseReversal-Free Internal ±7.5mV Comparator Hysteresis 20µs Comparator Propagation Delay Resettable Latched Comparator TS12011: Push-pull Rail-to-Rail Output Stage with Crowbar-Current Free Switching TS12012: Open-drain Output Stage for WiredOR or Mixed-Voltage System Applications The TS12011/TS12012 combine a 0.58V reference, a 20µs analog comparator, and a unity-gain stable operational amplifier in a single package. All three devices operate from a single 0.8V to 2.5V power supply and consume less than 1.6µA total supply current. Optimized for ultra-long life, single-cell and battery-powered applications, these devices expand Touchstone’s growing “NanoWatt Analog™” highperformance analog integrated circuits portfolio. Both the analog comparator and the op amp feature rail-to-rail input stages. The analog comparator exhibits ±7.5mV of internal hysteresis for clean, chatter-free output switching. The internal reference was designed to sink or source up to 0.1µA load currents. When compared against similar products, the TS12011 and the TS12012 offer a factor-of-20 lower power consumption and at least a 55% reduction in pcb area. APPLICATIONS The TS12011 and the TS12012 are fully specified over the -40°C to +85°C temperature range and each is available in a low-profile, 10-pin 2x2mm TDFN package with an exposed back-side paddle. Low-Frequency, Local-Area Alarms/Detectors Smoke Detectors and Safety Sensors Infrared Receivers for Remote Controls Instruments, Terminals, and Bar-Code Readers Battery-powered Systems Smart-Card Readers TYPICAL APPLICATION CIRCUIT Pilot Light Flame Detector with Low-Battery Lockout Circuit Part Number TS12011 TS12012 Comparator Output Stage Push-pull Open-Drain The Touchstone Semiconductor logo and “NanoWatt Analog” are registered trademarks of Touchstone Semiconductor, Incorporated. Page 1 © 2012 Touchstone Semiconductor, Inc. All rights reserved. TS12011/TS12012 ABSOLUTE MAXIMUM RATINGS Supply Voltage (VDD to VSS) ................................................. +2.75 V Input Voltage AMPIN+, AMPIN-…………………….….VSS – 0.3V to VDD + 0.3V COMPIN+, COMPIN-…..........................VSS – 0.3V to VDD + 0.3V T………………………………..…….….. VSS - 0.3V to +5.5V Output Voltage AMPOUT, REFOUT……….………….....VSS – 0.3V to VDD + 0.3V COMPOUT (TS12011)………….........…VSS - 0.3V to VDD + 0.3V COMPOUT (TS12012)……...…..………….…VSS - 0.3V to +5.5V Differential Input Voltage (AMPIN, COMPIN)........................ ±2.75V Output Current AMPOUT, COMPOUT…………………...............................50mA Short-Circuit Duration (REFOUT, AMPOUT, COMPOUT)………………...….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 ORDER NUMBER PART CARRIER QUANTITY MARKING TS12011ITD1022TP Tape & Reel TS12012ITD1022TP Tape & Reel ----- Tape & Reel 3000 ----- AAL TS12011ITD1022T AAM Tape & Reel 3000 TS12012ITD1022T Lead-free Program: Touchstone Semiconductor supplies only lead-free packaging. Consult Touchstone Semiconductor for products specified with wider operating temperature ranges. Page 2 TS12011_12DS r1p0 RTFDS TS12011/TS12012 ELECTRICAL CHARACTERISTICS VDD = 0.8V; VSS = 0V; VCOMPIN+/- = 0V; VAMPIN+/- = 0V; VAMPOUT = (VDD + VSS)/2; VCOMPOUT = 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 VDD 0.8 2.5 V TA = +25°C 1.1 1.6 Supply Current IDD REFOUT = open µA -40°C ≤ TA ≤ 85°C 2 REFERENCE SECTION TA = +25°C 555 577 600 Reference Output VREFOUT mV Voltage -40°C ≤ TA ≤ 85°C 552 602 Reference Load IOUT = ±100nA 0.5 % Regulation AMPLIFIER SECTION TA = +25°C 3.5 mV Input Offset Voltage VOS VAMPIN+/- = VDD or VAMPIN+/- = VSS -40°C ≤ TA ≤ 85°C 7 Input Bias Current Input Offset Current Input Common-Mode Range Large-Signal Voltage Gain Gain-Bandwidth Product Phase Margin Slew Rate Common-Mode Rejection Ratio Power-Supply Rejection Ratio Output High Voltage Output Low Voltage Output Source Current Output Sink Current Output Load Capacitive Drive IIN+, IN- VAMPIN+, VAMPIN- = (VDD – VSS)/2 IOS VAMPIN+, VAMPIN- = (VDD – VSS)/2 IVR Guaranteed by Input Offset Voltage Test VSS AVOL RL = 100K to VDD/2; VSS + 50mV < VOUT < VDD - 50mV 90 nA 5 nA VDD V 104 dB GBWP RL = 100kΩ//20pF 15 kHz φM SR RL = 100kΩ//20pF RL = 100kΩ//20pF 70 6 deg V/ms CMRR 0V ≤ VIN(CM) ≤ 2.1V; VDD = 2.5V 50 75 dB PSRR 0.65V ≤ (VDD - VSS) ≤ 2.5V 50 75 dB VOH VOL RL = 100kΩ to VSS RL = 100kΩ to VDD ISC+ VAMPOUT = VSS 0.28 mA ISC- VAMPOUT = VDD 4.5 mA VDD – 50mV VSS + 50mV COUT 50 V V pF VHB IIN+, INIOS IVR COMPARATOR SECTION TA = +25°C VAMPIN+/- = VDD; VAMPIN+/- = VSS; See Note 2 -40°C ≤ TA ≤ 85°C See Note 3 VCOMPIN+, VCOMPIN- = VDD or VSS VCOMPIN+, VCOMPIN- = VDD or VSS Guaranteed by Input Offset Voltage Test VSS CMRR 0V ≤ VIN(CM) ≤ 2.1V; VDD = 2.5V 50 60 dB PSRR 0.8V ≤ (VDD - VSS) ≤ 2.5V 50 70 dB 30 20 30 20 µs µs µs µs V V V mA mA mA nA Input Offset Voltage VOS Input Hysteresis Input Bias Current Input Offset Current Input Voltage Range Common-Mode Rejection Ratio Power-Supply Rejection Ratio Low-to-High Propagation Delay High-to-Low Propagation Delay Output High Voltage Output Low Voltage Output Low Voltage Output Short-Circuit Current 0.01 20 tPD+ tPDVOH VOL VOL ISC Open Drain Leakage TS12011_12DS r1p0 VOVERDRIVE = 10mV; See Note 4 TS12011 VOVERDRIVE = 100mV; See Note 4 VOVERDRIVE = 10mV; See Note 4 VOVERDRIVE = 100mV; See Note 4 TS12011; IOUT = -100μA TS12011 ; IOUT = 100μA TS12012 ; IOUT = 100μA Sourcing; VCOMPOUT = VSS TS12011 ; Sinking; VCOMPOUT = VDD TS12012 ; Sinking; VCOMPOUT = VDD TS12012 ; VCOMPOUT = 5V 4.5 8 mV ±7.5 0.2 mV nA nA V 20 5 VDD VDD – 0.1 VSS + 0.1 VSS + 0.11 0.1 0.5 1.4 20 Page 3 RTFDS TS12011/TS12012 VDD = 0.8V, VSS = 0V, VCOMPIN+/- = 0V, VAMPIN+/- = 0V, VAMPOUT = (VDD + VSS)/2, VCOMPOUT = 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 CONTROL PIN SECTION 0.1 Comparator Latched Output 0.8V ≤ VDD ≤ 1.1V VIL V T Input Low Voltage Enabled 1.1V < VDD ≤ 2.5V 0.2 VDD - 0.1 Comparator Latched Output 0.8V ≤ VDD ≤ 1.1V VIH V T Input High Voltage Disabled 1.1V < VDD ≤ 2.5V 1 T Input Leakage V T = VSS; V T = 5.5V 100 nA 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: VOS is defined as the center of the hysteresis band at the input. Note 3: The hysteresis-related trip points are defined by the edges of the hysteresis band and measured with respect to the center of the hysteresis band (i.e., VOS). Note 4: The propagation delays are specified with an output load capacitance of C L = 15pF. VOVERDRIVE is defined above and is beyond the offset voltage and hysteresis of the comparator input. Page 4 TS12011_12DS r1p0 RTFDS TS12011/TS12012 PIN FUNCTIONS PIN 1 2 3 4 NAME AMPOUT AMPINAMPIN+ VSS T 5 6 7 8 COMPIN+ REFOUT COMPIN- 9 COMPOUT 10 VDD EP ---- TS12011_12DS r1p0 FUNCTION Amplifier Output Amplifier Inverting Input Amplifier Non-inverting Input Negative Supply Voltage. Latch Enable Pin. When T is set HIGH, the output of the comparator will toggle normally based on the inputs to the comparator. For instance, when T is set LOW and the TS12011 output is HIGH, the output will remain HIGH despite any changes to the input of the comparator. The output will once again respond to changes to the input when T is toggled HIGH. If the output of the comparator is initially LOW and the T is then LOW, the output will stay LOW. If a LOW-toHIGH transition occurs on the output, the output will switch to HIGH and stay HIGH and not respond to any changes at the input. The T pin must always be set to a known state. The TS12012 output is the inverted version of the TS12011 output. For unlatched comparator operation, set T to HIGH. Comparator Non-inverting Input 0.58V Reference Output Comparator Inverting Input Comparator Output.TS12011 has a push-pull output stage. TS12012 has an open-drain output stage. Positive Supply Voltage. Connect a 0.1µF bypass capacitor from this pin to analog VSS/GND. Exposed paddle is electrically connected to VSS/GND. Page 5 RTFDS TS12011/TS12012 BLOCK DIAGRAM THEORY OF OPERATION The TS12011 and TS12012 combine a 0.58V ±4.5% reference, a 20µs analog comparator, and a unitygain stable operational amplifier in a single package. All three devices operate from a single 0.8V to 2.5V power supply and consume less than 1.6µA total supply current. The TS12011 comparator has a pushpull output stage while the TS12012 comparator has an open-drain output stage that allows for easy output voltage level translation as can occur when driving systems powered with a different power supply rail. Both the analog comparator and the op amp feature a common mode input range from VSS to VDD. The analog comparator exhibits ±7.5mV 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 TS12011 and the TS12012 have a latch enable pin T that allows the output of the comparator Page 6 to latch to either a HIGH or LOW state under certain conditions. If T is set HIGH, the COMPOUT output will respond to the applied comparator input. However, when T is set LOW and the TS12011 output is HIGH, COMPOUT will remain HIGH until T toggles LOW. When COMPOUT is initially LOW instead, COMPOUT will latch HIGH and remain HIGH on a LOW-to-HIGH transition at the input of the comparator until T goes HIGH. The TS12012 output is the inverted version of the TS12011 output. The T pin must not be left open and should be connected to VDD for normal unlatched operation or to VSS for latched operation. Op Amp The TS12011 and TS12012 have a unity-gain stable op-amp with a GBWP of 15kHz, a slew rate of 6V/ms, and can drive a capacitive load up to 50pF. The common mode input voltage range extends from VSS to VDD and the input bias current and TS12011_12DS r1p0 RTFDS TS12011/TS12012 input offset current are less than 20nA and 2nA, respectively. Comparator The TS12011 and TS12012 analog comparator input stage is robust as it can tolerate input voltages 300mV beyond the power supply rails. To insure clean output switching behavior, the analog comparator features ±7.5mV internal hysteresis. The TS12011 push-pull output driver was designed to minimize supply-current surges while driving ±100µA loads with an output swing to within 100mV of the supply rails. The open drain output stage TS12012 can be connected to supply voltages above VDD to an absolute maximum of 5.5V above VSS. Where wiredOR logic connections are needed, the open-drain output stage makes it easy to use this analog comparator. The TS12011 and the TS12012 can sink 0.5mA and 1.4mA of current, respectively. The TS12011 can source 0.1mA of current. Reference The TS12011 and TS12012 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 reference voltage will settle to within specifications in approximately 20ms. Op-Amp Stability The TS12011 and TS12012 op-amp is able to drive up to 50pF of capacitive load and still maintain stability in a unity-gain configuration with a 15kHz GBWP and a phase margin of 70 degrees with a 100kΩ//20pF output load. Though the TS12011 and TS12012 address low frequency applications, it is essential to perform good layout techniques in order to minimize board leakage and stray capacitance, which is of a concern in low power, high impedance circuits. For instance, a 10MΩ resistor coupled with a 1pF stray capacitance can lead to a pole at approximately 15kHz, which is the GBWP of the device. If stray capacitance is unavoidable, a feedback capacitor can be placed in parallel with the feedback resistor. APPLICATIONS INFORMATION Comparator Hysteresis As a result of circuit noise or unintended parasitic feedback, many analog comparators often break into oscillation within their linear region of operation especially when the applied differential input voltage approaches 0V (zero volt). Externally-introduced hysteresis is a well-established technique to stabilizing analog comparator behavior and requires external components. As shown in Figure 1, adding comparator hysteresis creates two trip points: VTHR (for the rising input voltage) and VTHF (for the falling input voltage). The hysteresis band (VHB) is defined as the voltage difference between the two trip points. When a comparator’s input voltages are equal, hysteresis effectively forces one comparator input to move quickly past the other input, moving the input out of the region where oscillation occurs. Figure 1 illustrates the case in which an IN- input is a fixed voltage and an IN+ is varied. If the input signals were reversed, the figure would be the same with an inverted output. To save cost and external pcb area, an internal ±7.5mV hysteresis circuit was added to the TS12011 and TS12012. TS12011_12DS r1p0 Figure 1. TS12011/TS12012 Threshold Hyesteresis Band Adding Hysteresis to the TS12011 Push-pull Output Option Additional hysteresis can be generated with three external resistors using positive feedback as shown in Figure 2. Unfortunately, this method also reduces the hysteresis response time. The procedure to calculate the resistor values for the TS12011 is as follows: Page 7 RTFDS TS12011/TS12012 falling). This is the threshold voltage at which the comparator switches its output from low to high as VCOMPIN+ rises above the trip point. In this example, VTHR is set to 2. 5) With the VTHR from Step 4 above, resistor R3 is then computed as follows: R3 = 1/[VTHR/(VREFOUT x R1) - (1/R1) - (1/R2)] R3 = 1/[2V/(0.58V x 160kΩ) - (1/160kΩ) (1/4.02MΩ)] = 66.43kΩ Figure 2. Using Three Resistors Introduces Additional Hysteresis in the TS12011 1) Setting R2. As the leakage current at the IN pin is less than 20nA, the current through R2 should be at least 150nA to minimize offset voltage errors caused by the input leakage current. The current through R2 at the trip point is (VREFOUT - VCOMPOUT)/R2. In solving for R2, there are two formulas – one each for the two possible output states: R2 = VREFOUT/IR2 In this example, a 69.8kΩ, 1% standard value resistor is selected for R3. 6) The last step is to verify the trip voltages and hysteresis band using the standard resistance values: For VCOMPIN+ rising: VTHR = VREFOUT x R1 [(1/R1) + (1/R2) + (1/R3)] = 1.93V or For VCOMPIN+ falling: R2 = (VDD - VREFOUT)/IR2 VTHF = VTHR - (R1 x VDD/R2) = 1.83V From the results of the two formulae, the smaller of the two resulting resistor values is chosen. For example, when using the TS12011 (VREFOUT = 0.58V) at a VDD = 2.5V and if IR2 = 150nA is chosen, then the formulae above produce two resistor values: 3.87MΩ and 12.8MΩ - a 4.02MΩ standard value for R2 is selected. and Hysteresis Band = VTHR – VTHF = 100mV 2) Next, the desired hysteresis band (VHYSB) is set. In this example, VHYSB is set to 100mV. 3) Resistor R1 is calculated according to the following equation: R1 = R2 x (VHYSB/VDD) and substituting the values selected in 1) and 2) above yields: R1 = 4.02MΩ x (100mV/2.5V) = 160.8kΩ. The 160kΩ standard value for R1 is chosen. 4) Page 8 The trip point for COMPIN+ rising (VTHR) is chosen such that VTHR > VREFOUT x (R1 + R2)/R2 (VTHF is the trip point for VCOMPIN+ TS12011_12DS r1p0 RTFDS TS12011/TS12012 Adding Hysteresis to the TS12012 Open-Drain Option The TS12012 has open-drain output and requires an external pull-up resistor to VDD as shown in Figure 3. R3 = 1/[VTHR/(VREFOUT x R1) - (1/R1) - (1/R2)] 6) As before, the last step is to verify the trip voltages and hysteresis band with the standard resistor values used in the circuit: For VCOMPIN+ rising: VTHR = VREFOUT x R1 x (1/R1+1/R2+1/R3) For VCOMPIN+ falling: VTHF = VREFOUT x R1 x(1/R1+1/R3+1/(R2+R4)) -(R1/(R2+R4)) x VDD and Hysteresis Band is given by VTHR – VTHF Figure 3. Using Four Resistors Introduces Additional Hysteresis in the TS12012 Additional hysteresis can be generated using positive feedback; however, the formulae differ slightly from those of the push-pull option TS12011. The procedure to calculate the resistor values for the TS12012 is as follows: 1) As in the previous section, resistor R2 is chosen according to the formulae: R2 = VREFOUT/150nA or R2 = (VDD- VREFOUT)/150nA - R4 where the smaller of the two resulting resistor values is the best starting value. 2) As before, the desired hysteresis band (VHYSB) is set to 100mV. 3) Next, resistor R1 is then computed according to the following equation: R1 = (R2 + R4) x (VHYSB/VDD) 4) The trip point for VCOMPIN+ rising (VTHR) is chosen (again, remember that VTHF is the trip point for VCOMPIN+ falling). This is the threshold voltage at which the comparator switches its output from low to high as VCOMPIN+ rises above the trip point. 5) With the VTHR from Step 4 above, resistor R3 is computed as follows: TS12011_12DS r1p0 Pilot Light Flame Detector with Low-Battery Lockout Circuit The TS12011 can be used to create a pilot flame detector with low-battery lockout circuit as shown in Figure 4. The circuit is able to detect when the thermocouple does not detect the pilot flame and when the battery in the circuit drops to 1.39V. This circuit makes use of the op-amp, comparator, and 0.58V reference in the TS12011. In this example, a type R thermocouple is used. It generates a voltage range from 9mV to 17mV that corresponds to a temperature range of 900ºC to 1500ºC, which is typical of a methane pilot flame. If the pilot flame is removed, the temperature drops; hence, the output voltage generated by the thermocouple is drops to a minimum voltage of 0.1mV that is applied to the noninverting input of the op-amp. This switches the output voltage of the op-amp to a LOW state and in turn, switches Q1 off. If, however, the battery voltage drops from 1.5V to 1.39V, the comparator output will switch from an output HIGH to a LOW. This will turn off Q2 and the output of the op-amp will turn Q1 off. The complete circuit consumes approximately 95µA of supply current at VDD = 1.5V. 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 engineering practice to make signal trace lengths as short as Page 9 RTFDS TS12011/TS12012 possible. Also recommended are a ground plane and surface mount resistors and capacitors. effect, all traces between the inputs of the comparator or op-amp and passive component networks should be made as short as possible. Input Noise Radiated noise is common in low power circuits that require high impedance circuits. To minimize this Figure 4. Pilot Light Flame Detector with Low-Battery Lockout Circuit Page 10 TS12011_12DS r1p0 RTFDS TS12011/TS12012 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 11 TS12011_12DS r1p0 RTFDS