SENSOR TRANSMITTER IC DELIVERY I OP OP G = 2.2 IN- 14

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1 SENSOR TRANSMTTER C FEATURES Wide Supply oltage Range: Wide Operating Temperature Range: 40 C C Small Package: SO 16 (n) Reference oltage Source: 5 Additional oltage or Current Source nstrumentation Amplifier with a Wide nput oltage Range Adjustable Gain and Offset Analog oltage (0...5/10), Current (0/4...20mA), and Output for A/D Converter Parallel Two and Three Wire Operation Protection Against Reverse Polarity APPLCATONS ndustrial Process Control Sensor Transmitter (e.g. pressure) Programmable Current Source GENERAL DESCRPTON is a monolithically integrated current transmitter which has been specially developed for the processing of differential bridge signals. The special feature of the device is the parallel voltage and current output. A high-precision instrumentation amplifier (A) serves as an input stage. A reference voltage source excites external components. Either a voltage-controlled current output stage or a voltage output stage convert the input signal. An operational amplifier is also integrated in the device which can be wired as either a current or a voltage source. t is thus possible to generate output currents and voltages which correspond to the normal industrial standards (0/4 20mA, 0 5/10). DELERY DL20/SO20(w) SO16(n) packages Dice on 5 blue foil BLOCK DAGRAM CREF REF SET CSET 2 5 Reference BG N+ 3 A 4 G = 2.2 N ZA GAN OUTAD NDA GND 11 RS+ 10 CC 9 RS- 8 OUT 12 OUT Figure 1 Analog Microelectronics GmbH Phone: +49 (0)6131/ /10 An der Fahrt 13, D Mainz Fax: +49 (0)6131/ Rev. 3.1 nternet: E Mail: info@analogmicro.de

2 SENSOR TRANSMTTER C ELECTRCAL SPECFCATONS T amb = 25 C, CC = 24, REF = 5, REF = 1mA (unless otherwise noted) Parameter Symbol Conditions Min. Typ. Max. Unit oltage Range CC 6 35 Quiescent Current CC T amb = C, REF = 0mA 1.5 ma Temperature Specifications Operating T amb C Storage T st C Junction T J 150 C Thermal Resistance Θ ja DL16 plastic package 70 C/W Θ ja SO16 narrow plastic package 140 C/W oltage Reference oltage REF SET not connected REF** SET = GND, CC Trim Range R10** 4.5 R10 Current REF* ma REF vs. Temperature d REF/dT T amb = C ±90 ±140 ppm/ C Line Regulation d REF/d CC = ppm/ d REF/d CC = , REF 5mA ppm/ Load Regulation d REF/d %/ma d REF/d REF 5mA %/ma Load Capacitance C L µf Current/oltage Source nternal Reference BG BG vs. Temperature d BG/dT T amb = C ±60 ±140 ppm/ C Current Source: C = BG/R EXT Adjustable Current Range C* 0 10 ma Output oltage C CC < 19 BG CC 4 C CC 19 BG 15 oltage Source: C = BG (R EXT1 + R EXT2) / R EXT2 Adjustable oltage Range C CC < CC 4 C CC Output Current C* Source 10 ma C Sink 100 µa Load Capacitance C L Source mode nf nstrumentation Amplifier nternal Gain G A Differential nput oltage Range N 0 ±400 m Common Mode nput Range CMR CC < 9, C < 2mA 1.5 CC 3 CMR CC 9, C < 2mA Common Mode Rejection Ratio CMRR db Power Supply Rejection Ratio PSRR db Offset oltage OS ±1.5 ±6 m OS vs. Temperature d OS/dT ±5 µ/ C nput Bias Current B na B vs. Temperature d B/dT na/ C 2/10

3 SENSOR TRANSMTTER C Parameter Symbol Conditions Min. Typ. Max. Unit nstrumentation Amplifier (cont.) Output oltage Range OUTA CC < 9, R LA 10kΩ 0*** CC 4 OUTA CC 9, R LA 10kΩ 0*** 5 Minimum Output oltage OUTAmin without external load resistance R LA m Load Capacitance C L** 250 pf Zero Adjust Stage nternal Gain G ZA 1 nput oltage ZA ZA OUTA G A N 0 OUTA Offset oltage OS ±0.5 ±2.0 m OS vs. Temperature d OS/dT ±1.6 ±5 µ/ C nput Bias Current B na B vs. Temperature d B/dT pa/ C Operational Amplifier Gain Stage Adjustable Gain G GAN 1 nput Range R CC < 10 0 CC 5 R CC Power Supply Rejection Ratio PSRR db Offset oltage OS ±0.5 ±2 m OS vs. Temperature d OS/dT ±3 ±7 µ/ C nput Bias Current B na B vs. Temperature d B/dT 7 20 pa/ C Output oltage Limitation LM REF Output oltage Range OUTAD CC < 10 0 CC 5 OUTAD CC 10 0 REF Load Capacitance C L 250 pf Operational Amplifier Output Stage nternal Gain G nput Range R CC < 11 0 CC 5 R CC Power Supply Rejection Ratio PSRR db Offset oltage OS ±0.5 ±2 m OS vs. Temperature d OS/dT ±3 ±7 µ/ C nput Bias Current B na B vs. Temperature d B/dT 7 20 pa/ C Output oltage Range OUT CC < 19 0 CC 5 OUT CC Output Current Limitation LM OUT ma Output Current OUT 0 LM ma Load Resistance R L 2 kω Load Capacitance C L 500 nf / Converter nternal Gain G Trim Range adjustable by R oltage Range at R 0 FS R0FS m Offset oltage OS β F 100 ±2 ±4 m OS vs. Temperature d OS/dT β F 100 ±7 ±14 µ/ C 3/10

4 SENSOR TRANSMTTER C Parameter Symbol Conditions Min. Typ. Max. Unit / Converter (cont.) nput Resistance R N kω R N vs. Temperature dr N/dT kω/ C Output Offset Current OUTOS 3 wire operation µa OUTOS vs. Temperature d OUTOS/dT 3 wire operation na/ C Output Offset Current OUTOS 2 wire operation µa OUTOS vs. Temperature d OUTOS/dT 2 wire operation 6 8 na/ C Output Control Current OUTC 2 wire operation, R0/100m 6 8 µa OUTC vs. Temperature d OUTC/dT 2 wire operation na/ C Output oltage Range OUT OUT = R L OUT, CC < 18 0 CC 6 OUT OUT = R L OUT, CC Output Current Range FS OUTFS OUT = R0/R 0, 3 wire operation 20 ma Output Resistance R OUT MΩ Load Capacitance C L nf SET Stage nternal Gain G SET 0.5 nput oltage SET Offset oltage OS ±0.5 ±1.5 m OS vs. Temperature d OS/dT ±1.6 ±5 µ/ C nput Bias Current B 8 20 na B vs. Temperature d B/dT 7 18 pa/ C Protection Functions oltage Limitation at R 0 LMR0 R0 = N G, SET = GND REF/8 m LMR0 N = 0, R0 = SET/ m Protection against reverse polarity Ground vs. S vs. OUT 35 Ground vs. S vs. OUT 35 Current in case of reverse polarity Ground = 35, S = OUT = ma System Parameters Nonlinearity ideal input %FS * n 2 wire operation a maximum current of OUTmin CC is valid ** Only available in die form or 20 pin DL version *** Depending on external load resistance at output of A (R LA 10kΩ OUTA < 3m); internal load resistance is 100kΩ Currents flowing into the C are negative BOUNDARY CONDTONS Parameter Symbol Conditions Min. Typ. Max. Unit Sense Resistor R 0 OUTFS = 20mA Ω R 0 c = 20mA/ OUTFS c 17 c 27 c 38 Ω Stabilisation Resistor R 5 OUTFS = 20mA Ω R 5 c = 20mA/ OUTFS c 35 c 40 c 45 Ω Load Resistance R L limitation only for 3 wire operation Ω Sum Offset Resistors R 3 + R kω REF Capacitance C µf Output Capacitance C 2 only for 2 wire operation nf D 1 Breakdown oltage BR T 1 Forward Current Gain β F /10

5 SENSOR TRANSMTTER C FUNCTONAL DAGRAMS 3 Wire System S R A oltage Reference or Current Source OUT N R N A OUT R B R L Figure 2 Ground FUNCTONAL DESCRPTON is a monolithically integrated current transmitter which has been specially developed for the processing of differential bridge signals. By varying a few external components, the output current can be set to various values within a wide range. Only an external output transistor T 1 and a diode D 1 are needed (See Figure 7 and Figure 8) in addition to the resistors R 0 R 5 and the capacitor C 1 (C 2 ). The external transistor decreases the power dissipation of the C and the diode protects the transistor against reverse polarity. The maximum power dissipation of the components must be taken into consideration when selecting the transistor and diode. Typical values for the external components are given in the following Description of Applications. can principally be used in the implementation of two- and three-wire systems for industrial applications. t has to be taken into account that in applications with parallel current and voltage output only 3-wire operation is possible. A schematic diagram illustrates a three-wire system in Figure 2. Here, the differential input voltage ( N ) is shown as a variable resistor. The external reference point Ground is identical to the ground of the C (GND) and the supply voltage of the C matches that of the system: CC = S. n two-wire configurations, however, the ground of the C (GND) is connected between resistors R 5 and R L. n this instance, the supply voltage of the C ( CC ) is dependent on the supply voltage of the system ( S ) and the value of the load resistor (R L ). t can be calculated using the equation: CC = S OUT RL AM 400 is basically made up of the following function blocks (see Figure 1): 1. A high accuracy instrumentation amplifier (A) with an internal gain G A and the possibility to adjust the bias voltage (pin ZA) is used for differential input signals. 2. Following to the A an operational amplifier stage is integrated, which allows to adjust the gain of the whole system. As a special function an voltage limitation following the value of the voltage reference is integrated. 3. At the voltage-controlled current output an offset current can be set at the output with the help of the internal voltage reference across external resistors R 3 and R 4. Output current OUT is provided by external transistor T 1 which is driven by the current output (OUT) of the C. Using current and voltage output at 5/10

6 SENSOR TRANSMTTER C the same time a fine adjustment of the current output is possible by variation of R 0. A safety feature included in is the integrated power-down function with excessive temperature. With this, the output current is switched off if the C gets too warm. 4. An operational amplifier stage represents the voltage output of the C. The amplifier stage has an internal gain of G = The adjustable reference voltage source supplies sensors or other external components with voltage of 5 or 10 (SET = N.C. or SET = GND). Additionally, any voltage value between 4.5 and 10 can be set via an external voltage divider. mportant: Please note, that Capacitor C 1 (ceramic) must also be connected even when the voltage reference is not used. 6. The additional operational amplifier can be used as a current or voltage source for external components. mportant: Not used function blocks have to be connected. The capacitors C 1 and C 2 have to be connected to the C in any case even when the voltage reference is not used! NTAL ERATON OF 1 SO16 oltage output The transfer function of the output voltage of the adjustable gain stage is: OUTAD ( GAN + ZA ) GGAN = mit G GAN R 1 = + 1 R2 and the offset voltage ZA which is adjustable on pin ZA (e.g. by usage of the additional operational amplifier, please see the Application Notes). For the entire output voltage of the C is valid OUT = G NDA The minimum supply voltage S which has to be connected is depending on the maximum output voltage: Current output S OUTmax + 5 To compensate the offset of the output current for the first time, the input must be short-circuited ( N = 0). n doing so, it should be ensured that the input pins of the instrumentation amplifier have the voltage potentials given in the Electrical Specifications (input voltage range). The short circuit at the input produces an output current OUT = SET with SET ( 0) N REF R4 = = 2 R 0 R + R 3 4 The adjustment of the output current range depends on the choice of external resistors R 1 and R 2. The maximum output current is defined by the general transfer function of the C. The following equation is given for the output current OUT : OUT G = N + R SET mit G ( ) 8 = GA 1+ R1 R2 0 The gain factor of the current output stage G is determined by the input voltage N and the maximum output current OUTmax. The minimum supply voltage is dependent on the value of the reference voltage. The following applies: 6/10

7 SENSOR TRANSMTTER C CC REF +1. The choice of supply voltage S also depends on the load resistor R L used by the application. The following inequation determines the minimum supply voltage: S OUTmax RL + CCmin. The resulting operating area is shown in Figure 3. Example calculations and values for the external components are listed in the Application Notes. R L [Ω] 600 R L S CCmin OUTmax CCmin R Lmax = 6 = 600Ω OUTmax = 20mA 300 Operating Area S [] Figure 3 7/10

8 SENSOR TRANSMTTER C PNOUT 1 SO16N CREF CSET N+ N GAN OUTAD NDA OUT Figure 4 DELERY SET REF GND ZA OUT RS+ CC RS PN NAME BEDEUTUNG 1 CREF Current/oltage Reference 2 CSET Adjustment Current/oltage Reference 3 N+ nput Positive 4 N nput Negative 5 GAN Adjustment Gain 6 OUTAD Output for A/D Converter 7 NDA nput for Output Stages 8 OUT Current Output 9 RS Sense Resistor 10 CC Supply oltage 11 RS+ Sense Resistor + 12 OUT oltage Output 13 ZA Zero Adjustment 14 GND C Ground 15 REF Output Reference oltage 16 SET Adjustment Output Offset Current The 1 is available in version: SO 16 (n) packages (maximum power dissipation P D = 300mW) PACKAGE DMENSONS SO16 (n) 10,06 ± 0,1 4,0 + 0,2-0,1 2,00 1,45 ± 0,1 0,2 ± 0,1 0,42 ± 0,07 1,27 0,635 0,2 ± 0,05 0,3 6,2 ± 0, Figure 5 8 8/10

9 SENSOR TRANSMTTER C TYPCAL APPLCATON (4 20mA/0 10) C 1 R 3 R 4 S R SET BG A Reference G = T 1 R 0 D 1 OUT R 5 OUT R 2 R 1 R L Figure 6 n 3 wire operation (Figure 6) pin 11 (CC) has to be connected with pin 10 (RS+), and C ground pin 14 (GND) has to be connected with Ground. For the output voltage is valid (ZA = GND) OUT = G N with G = GA GGAN G For the output current in a 4 20mA application is valid G OUT = N + SET with G = GA GGAN 8R 0 with the output offset current SET ( 0) N REF R4 = = 2 R 0 R + R 3 4 The measurement bridge is current supplied by the additional. The supply current S can be adjusted by the variation of the resistor R SET S = R BG SET Example: Output current range mA, output voltage range With N = 0K100m the following values for the external components are valid: R Ω R kΩ R 2 = 10kΩ R 3 = 82kΩ R kΩ R 5 = 39Ω R L = Ω C 1 = 2.2µF Ground 9/10

10 SENSOR TRANSMTTER C BLOCK DAGRAM 20 PN ERSON AND DCE CSET BG CREF SET REF SET oltage Reference A G = ZA GAN GND OUTA N OUTAD NDA NDA 2 N+ 3 4 N- 14 RS+ 13 CC 12 RS- 11 OUT 15 OUT Figure 7 PNOUT 20 PN ERSON CREF CSET N+ N OUTA N GAN OUTAD NDA NDA Figure SET REF GND ZA SET OUT RS+ CC RS OUT DELERY 20 PN ERSON 20 pin DL SO 20 (w) packages Dice on 5 blue foil PN NAME DESGNATON 1 CREF Current/oltage Reference 2 CSET Adjustment Current/oltage Reference 3 N+ nput Positive A 4 N nput Negative A 5 OUTA Output A 6 N nput Positive Gain Amplifier 7 GAN Adjustment Gain 8 OUTAD Output for A/D Converter 9 NDA nput for Current Output Stage 10 NDA nput for oltage Output Stage 11 OUT Current Output 12 RS Sense Resistor 13 CC Supply oltage 14 RS+ Sense Resistor + 15 OUT oltage Output 16 SET Adjustment Reference oltage 17 ZA Zero Adjustment 18 GND C Ground 19 REF Output Reference oltage 20 SET Adjustment Output Offset Current The information provided herein is believed to be reliable; however, Analog Microelectronics assumes no responsibility for inaccuracies or omissions. Analog Microelectronics assumes no responsibility for the use of this information, and all use of such information shall be entirely at the user's own risk. Prices and specifications are subject to change without notice. No patent rights or licences to any of the circuits described herein are implied or granted to any third party. Analog Microelectronics does not authorise or warrant any Analog Microelectronics product use in life support devices and/or systems. 10/10