XTR117AIDRBTG4

XTR117 SBOS344C − SEPTEMBER 2005 − REVISED MAY 2012 4-20mA Current-Loop Transmitter FEATURES DESCRIPTION D D D D D D The XTR117 is a precision current output converter designed to transmit analog 4-20mA signals over an industry-standard current loop. It provides accurate current scaling and output current limit functions. LOW QUIESCENT CURRENT: 130μA 5V REGULATOR FOR EXTERNAL CIRCUITS LOW SPAN ERROR: 0.05% LOW NONLINEARITY ERROR: 0.003% WIDE-LOOP SUPPLY RANGE: 7.5V to 40V MSOP-8 AND DFN-8 PACKAGES The on-chip voltage regulator (5V) can be used to power external circuitry. A current return pin (IRET) senses any current used in external circuitry to assure an accurate control of the output current. APPLICATIONS The XTR117 is a fundamental building block of smart sensors using 4-20mA current transmission. The XTR117 is specified for operation over the extended industrial temperature range, −40°C to +125°C. D TWO-WIRE, 4-20mA CURRENT LOOP D D D D D TRANSMITTER SMART TRANSMITTER INDUSTRIAL PROCESS CONTROL TEST SYSTEMS CURRENT AMPLIFIER VOLTAGE-TO-CURRENT AMPLIFIER RELATED 4-20mA PRODUCTS XTR115 5V regulator output and 2.5V reference output XTR116 5V regulator output and 4.096V reference output NOTE: For 4-20mA complete bridge and RTO conditioner solutions, see the XTR product family website at www.ti.com. XTR117 VREG 8 7 B 6 RIN IO V+ +5V Regulator Q1 I IN 2 VLOOP A1 E VIN RLIM IRET 3 R1 2.475kΩ R2 25Ω 5 RL IO = 100 VIN RIN 4 Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet. All trademarks are the property of their respective owners. Copyright © 2005−2006, Texas Instruments Incorporated PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters. www.ti.com XTR117 www.ti.com SBOS344C − SEPTEMBER 2005 − REVISED MAY 2012 ELECTROSTATIC DISCHARGE SENSITIVITY ABSOLUTE MAXIMUM RATINGS(1) Power Supply, V+ (referenced to IO pin) . . . . . . . . . . . . . . . . . +50V Input Voltage, (referenced to IRET pin) . . . . . . . . . . . . . . . . . 0V to V+ Output Current Limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . Continuous VREG, Short-Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Continuous Operating Temperature Range . . . . . . . . . . . . . . . −55°C to +125°C Storage Temperature Range . . . . . . . . . . . . . . . . . −55°C to +150°C Junction Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +165°C ESD Rating (Human Body Model) . . . . . . . . . . . . . . . . . . . . . . . 2000V (Charged Device Model) . . . . . . . . . . . . . . . . . 1000V (1) This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage. ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more susceptible to damage because very small parametric changes could cause the device not to meet its published specifications. Stresses above these ratings may cause permanent damage. Exposure to absolute maximum conditions for extended periods may degrade device reliability. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those specified is not implied. PACKAGE/ORDERING INFORMATION(1) (1) PRODUCT PACKAGE-LEAD PACKAGE DESIGNATOR PACKAGE MARKING XTR117 MSOP 8 MSOP-8 DGK BOZ XTR117 DFN 8 DFN-8 DRB BOY For the most current package and ordering information see the Package Option Addendum at the end of this document, or see the TI web site at www.ti.com. PIN ASSIGNMENTS Top View XTR117 NC(1) 1 XTR117 8 VREG IIN 2 7 V+ IRET 3 6 B (Base) IO 4 5 E (Emitter) MSOP−8 NC(1) 1 I IN 2 IRET 3 IO 4 Exposed Thermal Die Pad on Underside(2) DFN−8 NOTES: (1) NC = No connection. Leave unconnected on PCB. (2) Connect thermal die pad to IRET or leave unconnected on PCB. 2 8 VREG 7 V+ 6 B (Base) 5 E (Emitter) XTR117 www.ti.com SBOS344C − SEPTEMBER 2005 − REVISED MAY 2012 ELECTRICAL CHARACTERISTICS: V+ = +24V Boldface limits apply over the temperature range, TA = −40°C to +125°C. All specifications at TA = +25°C, V+ = 24V, RIN = 20kΩ, and TIP29C external transistor, unless otherwise noted. PARAMETER OUTPUT Output Current Equation Output Current, Linear Range Over-Scale Limit Under-Scale Limit SPAN Span (Current Gain) Error(1) vs Temperature Nonlinearity INPUT Offset Voltage (Op Amp) vs Temperature vs Supply Voltage, V+ Bias Current vs Temperature Noise: 0.1Hz to 10Hz CONDITION IO ILIM IMIN IREG = 0 0.20 IO = 200μA to 25mA TA = −40°C to +125°C IO = 200μA to 25mA 100 ±0.05 ±3 ±0.003 ±0.4 ±20 ±0.02 A/A % ppm/°C % IIN = 40μA TA = −40°C to +125°C V+ = 7.5V to 40V ±100 ±0.7 +0.1 −35 150 0.6 IB TA = −40°C to +125°C en IREG = 0 TA = −40°C to +125°C V+ = 7.5V to 40V (2) 25 mA mA mA VREG(2) Voltage Voltage Accuracy vs Temperature vs Supply Voltage, V+ vs Output Current Short-Circuit Current (1) UNITS 32 0.13 S VOS MAX IO = IIN x 100 CLOOP = 0, RL = 0 TEMPERATURE RANGE Specified Range Operating Range Storage Range Thermal Resistance MSOP DFN XTR117 TYP 0.20 DYNAMIC RESPONSE Small-Signal Bandwidth Slew Rate POWER SUPPLY Specified Voltage Range Operating Voltage Range Quiescent Current Over Temperature MIN ±500 ±6 +2 380 3.2 kHz mA/μs 5 ±0.05 ±0.1 ±0.1 1 See Typical Characteristics 12 V+ +24 +7.5 IQ 130 TA = −40°C to +125°C −40 −55 −55 μV μV/°C μV/V nA pA/°C μVPP V V mV/°C mV/V mA +40 200 250 V V μA μA +125 +125 +150 °C °C °C qJA 150 53 °C/W °C/W Does not include initial error or temperature coefficient of RIN. Voltage measured with respect to IRET pin. 3 XTR117 www.ti.com SBOS344C − SEPTEMBER 2005 − REVISED MAY 2012 TYPICAL CHARACTERISTICS: V+ = +2.7V to +5.5V At TA = +25°C, V+ = 24V, RIN = 20kΩ, and TIP29C external transistor, unless otherwise noted. QUIESCENT CURRENT vs TEMPERATURE CURRENT GAIN vs FREQUENCY 45 180 170 COUT = 0 RL = 0Ω 30 COUT = 10nF RL = 250Ω 20 160 Quiescent Current (μA) Gain (dB) 40 150 V+ = 36V 140 130 120 V+ = 24V 110 100 V+ = 7.5V 90 10 10k 100k 80 1M −75 −50 −25 Frequency (Hz) 25 50 75 100 5.5 +125_C With External Transistor 33 VREG Voltage (V) −55_ C 32 V+ = 36V 31 V+ = 7.5V 30 V+ = 24V 5.0 +25_C −55_ C +25_ C Sinking Current 29 Sourcing Current +125_ C 4.5 28 −75 −50 −25 0 25 50 75 100 −1 125 0 1 2 3 IREG Current (mA) Temperature (_ C) OFFSET VOLTAGE DISTRIBUTION SPAN ERROR vs TEMPERATURE 50 40 20 Population Span Error (m%) 30 10 0 −10 −20 −30 −75 −50 −25 0 25 50 Temperature (_C) 4 75 100 125 −500 −450 −400 −350 −300 −250 −200 −150 −100 −50 0 50 100 150 200 250 300 350 400 450 500 −40 −50 125 VREG VOLTAGE vs VREG CURRENT OVER−SCALE CURRENT vs TEMPERATURE 34 Over−Scale Current (mA) 0 Temperature (_C) Offset Voltage (μV) 4 XTR117 www.ti.com SBOS344C − SEPTEMBER 2005 − REVISED MAY 2012 APPLICATIONS INFORMATION EXTERNAL TRANSISTOR BASIC OPERATION The external transistor, Q1, conducts the majority of the full-scale output current. Power dissipation in this transistor can approach 0.8W with high loop voltage (40V) and 20mA output current. The XTR117 is designed to use an external transistor to avoid on-chip, thermal-induced errors. Heat produced by Q1 will still cause ambient temperature changes that can influence the XTR117 performance. To minimize these effects, locate Q1 away from sensitive analog circuitry, including XTR117. Mount Q1 so that heat is conducted to the outside of the transducer housing. The XTR117 is a precision current output converter designed to transmit analog 4-20mA signals over an industry-standard current loop. Figure 1 shows basic circuit connections with representative simplified input circuitry. The XTR117 is a two-wire current transmitter. Its input current (pin 2) controls the output current. A portion of the output current flows into the V+ power supply, pin 7. The remaining current flows in Q1. External input circuitry connected to the XTR117 can be powered from VREG. Current drawn from these terminals must be returned to IRET, pin 3. The IRET pin is a local ground for input circuitry driving the XTR117. The XTR117 is designed to use virtually any NPN transistor with sufficient voltage, current and power rating. Case style and thermal mounting considerations often influence the choice for any given application. Several possible choices are listed in Figure 1. A MOSFET transistor will not improve the accuracy of the XTR117 and is not recommended. The XTR117 is a current-input device with a gain of 100. A current flowing into pin 2 produces IO = 100 x IIN. The input voltage at the IIN pin is zero (referred to the IRET pin). A voltage input is converted to an input current with an external input resistor, RIN, as shown in Figure 1. Typical full-scale input voltages range from 1V and upward. Full-scale inputs greater than 0.5V are recommend to minimize the effects of offset voltage and drift of A1. For improved precision use an external voltage reference. Possible choices for Q1 (see text): DEVICE VOLTAGE TYPE PACKAGE REF3140 REF3130 REF3125 4.096V 3.0V 2.5V MJE3440 TIP41C MJD3340 SOT−32 TO−220 D−PAK Use REF32xx for lower drift. (VREF) 5V IREG VREG XTR117 8 Input Circuitry VIN RIN 20kΩ 7 B 6 IIN Q1 VLOOP IIN 2 A1 E R LIM IRET from I REG and IREF All return current IO V+ +5V Regulator 3 R1 2.475kΩ R2 25Ω COUT 10nF 5 RL IO 4 I = 100 (IIN) Figure 1. Basic Circuit Connections 5 XTR117 www.ti.com SBOS344C − SEPTEMBER 2005 − REVISED MAY 2012 MINIMUM OUTPUT CURRENT MAXIMUM OUTPUT CURRENT The quiescent current of the XTR117 (typically 130μA) is the lower limit of its output current. Zero input current (IIN = 0) will produce an IO equal to the quiescent current. Output current will not begin to increase until IIN > IQ/100. Current drawn from VREG will be added to this minimum output current. Up to 3.8mA is available to power external circuitry while still allowing the output current to go below 4mA. The XTR117 provides accurate, linear output up to 25mA. Internal circuitry limits the output current to approximately 32mA to protect the transmitter and loop power/measurement circuitry. It is possible to extend the output current range of the XTR117 by connecting an external resistor from pin 3 to pin 5, to change the current limit value. Since all output current must flow through internal resistors, it is possible to cause internal damage with excessive current. Output currents greater than 45mA may cause permanent damage. OFFSETTING THE INPUT A low-scale output of 4mA is produced by creating a 40μA input current. This input current can be created with the proper value resistor from an external reference voltage (VREF) as shown in Figure 2. VREG can be used as shown in Figure 2 but will not have the temperature stability of a high quality reference such as the REF3125. VREF (2.5V) or VREG ................... 8 RIN 62.5kΩ REVERSE-VOLTAGE PROTECTION The XTR117 low compliance voltage rating (minimum operating voltage) of 7.5V permits the use of various voltage protection methods without compromising operating range. Figure 3 shows a diode bridge circuit which allows normal operation even when the voltage connection lines are reversed. The bridge causes a two diode drop (approximately 1.4V) loss in loop supply voltage. This voltage drop results in a compliance voltage of approximately 9V—satisfactory for most applications. A diode can be inserted in series with the loop supply voltage and the V+ pin to protect against reverse output connection lines with only a 0.7V loss in loop supply voltage. XTR117 40μA IIN 2 A1 0 to 160μA IRET 3 R1 2.475kΩ Figure 2. Creating Low-Scale Offset XTR117 V REG V+ +5V Regulator 8 7 B 6 R IN Maximum V PS must be less than minimum voltage rating of the zener diode. Q1 IIN 2 A1 0.01μF E V IN D 1(1 ) IN4148 5 R LIM IR E T 3 R1 2.475kΩ R2 25Ω RL I O = 100 V IN R IN 4 The diode bridge causes a 1.4V loss in loop supply voltage. See Reverse−Voltage Protection. NOTE: (1) Some examples of zener diodes include: P6KE51 or 1N4755A. Use lower voltage zener diodes with loop power−supply voltages < 30V for increased protection. See Over−voltage Surge Protection. Figure 3. Reverse Voltage Operation and Over-Voltage Surge Protection 6 VL OO P XTR117 www.ti.com SBOS344C − SEPTEMBER 2005 − REVISED MAY 2012 OVER-VOLTAGE SURGE PROTECTION Remote connections to current transmitters can sometimes be subjected to voltage surges. It is prudent to limit the maximum surge voltage applied to the XTR117 to as low as practical. Various zener diode and surge clamping diodes are specially designed for this purpose. Select a clamp diode with as low a voltage rating as possible for best protection. Absolute maximum power-supply rating on the XTR117 is specified at +50V. Keep overvoltages and transients below +50V to ensure reliable operation when the supply returns to normal (7.5V to 40V). Most surge protection zener diodes have a diode characteristic in the forward direction that will conduct excessive current, possibly damaging receiving-side circuitry if the loop connections are reversed. If a surge protection diode is used, a series diode or diode bridge should be used for protection against reversed connections. RADIO FREQUENCY INTERFERENCE The long wire lengths of current loops invite radio frequency (RF) interference. RF interference can be rectified by the input circuitry of the XTR117 or preceding circuitry. This effect generally appears as an unstable output current that varies with the position of loop supply or input wiring. Interference may also enter at the input terminals. For integrated transmitter assemblies with short connections to the sensor, the interference more likely comes from the current loop connections. VREG XTR117 8 RIN VO D/A IIN 2 IRET 3 VREG XTR117 8 Digital Control Optical Isolation IIN IO D/A 2 IRET 3 VREG XTR117 8 Digital Control μC Optical Isolation PWM Out RFILTER RIN IIN 2 CFILTER IRET 3 Figure 4. Digital Control Methods 7 XTR117 www.ti.com SBOS344C − SEPTEMBER 2005 − REVISED MAY 2012 VS Nonlinear Bridge Transducer P 0 ps i Linearization Circuit PGA309 50 Ref 2.5V XTR117 VR E G +5V Regulator Lin DAC 8 Analog Sensor Linearization Fault Monitor Auto−Zero PGA Over/Under Scale Limiter Linear V O U T (1) RIN 25kΩ 7 B 6 RO S 125kΩ II N A1 E Analog Signal Conditioning T −40_C Ext Temp Ext Temp 5 RL IM IR E T Temp ADC Control Register Interface Circuitry Q1 VL O O P 2 +125_C Digital Int Temp Temperature Compensation IO V+ 3 R1 2.475kΩ R2 25Ω RL IO = 100 VI N RIN 4 EEPROM (SOT23−5) Digital Calibration NOTE: (1) PGA309 V O UT : 0.5V to 4.5V. Figure 5. Complete 4-20mA Pressure Transducer Solution with PGA309 and XTR117 DFN PACKAGE LAYOUT GUIDELINES The XTR117 is offered in a DFN-8 package (also known as SON). The DFN is a QFN package with lead contacts on only two sides of the bottom of the package. This leadless package maximizes board space and enhances thermal and electrical characteristics through an exposed pad. The exposed leadframe die pad on the DFN package should be soldered to a thermal pad on the PCB. A mechanical drawing showing an example layout is attached at the end of this data sheet. Refinements to this layout may be required based on assembly process requirements. Mechanical drawings located at the end of this data sheet list the physical dimensions for the package and pad. The five holes in the landing pattern are optional, and are intended for use with thermal vias that connect the leadframe die pad to the heatsink area on the PCB. DFN packages are physically small, have a smaller routing area, improved thermal performance, and improved electrical parasitics. Additionally, the absence of external leads eliminates bent-lead issues. The DFN package can be easily mounted using standard printed circuit board (PCB) assembly techniques. See Application Note, QFN/SON PCB Attachment (SLUA271) and Application Report, Quad Flatpack No-Lead Logic Packages (SCBA017), both available for download at www.ti.com. The exposed leadframe die pad on the bottom of the package should be connected to IRET or left unconnected. 8 Soldering the exposed pad significantly improves board-level reliability during temperature cycling, key push, package shear, and similar board-level tests. Even with applications that have low power dissipation, the exposed pad must be soldered to the PCB to provide structural integrity and long-term stability. PACKAGE OPTION ADDENDUM www.ti.com 13-Aug-2021 PACKAGING INFORMATION Orderable Device Status (1) Package Type Package Pins Package Drawing Qty Eco Plan (2) Lead finish/ Ball material MSL Peak Temp Op Temp (°C) Device Marking (3) (4/5) (6) XTR117AIDGKR ACTIVE VSSOP DGK 8 2500 RoHS & Green NIPDAU | NIPDAUAG Level-3-260C-168 HR -40 to 125 BOZ XTR117AIDGKRG4 ACTIVE VSSOP DGK 8 2500 RoHS & Green Level-3-260C-168 HR -40 to 125 BOZ XTR117AIDGKT ACTIVE VSSOP DGK 8 250 RoHS & Green NIPDAU | NIPDAUAG Level-3-260C-168 HR -40 to 125 BOZ XTR117AIDRBR ACTIVE SON DRB 8 3000 RoHS & Green NIPDAU Level-3-260C-168 HR -40 to 125 BOY XTR117AIDRBT ACTIVE SON DRB 8 250 RoHS & Green NIPDAU Level-3-260C-168 HR -40 to 125 BOY NIPDAU (1) The marketing status values are defined as follows: ACTIVE: Product device recommended for new designs. LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect. NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design. PREVIEW: Device has been announced but is not in production. Samples may or may not be available. OBSOLETE: TI has discontinued the production of the device. (2) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may reference these types of products as "Pb-Free". RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption. Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of