MAX15500

19-4602; Rev 1; 2/11 TION KIT EVALUA BLE ILA AVA Industrial Analog Current/ Voltage-Output Conditioners Features S Supply Voltage Up to Q32.5V S Output Protected Up to Q35V S Programmable Output (Plus Overrange) General Description The MAX15500/MAX15501 analog output conditioners provide a programmable current up to Q24mA, or a voltage up to Q12V proportional to a control voltage signal. The control voltage is typically supplied by an external DAC with an output voltage range of 0 to 4.096V for the MAX15500 and 0 to 2.5V for the MAX15501. The output current and voltage are selectable as either unipolar or bipolar. In the unipolar configuration, a control voltage of 5% full-scale (FS) produces a nominal output of 0A or 0V to achieve underrange capability. A control voltage of 100%FS produces one of two programmable levels (105%FS or 120%FS) to achieve overrange capability. The outputs of the MAX15500/MAX15501 are protected against overcurrent conditions and a short to ground or supply voltages up to Q35V. The devices also monitor for overtemperature and supply brownout conditions. The supply brownout threshold is programmable. The MAX15500/MAX15501 are programmed through an SPIK interface capable of daisy-chained operation. The MAX15500/MAX15501 provide extensive error reporting through the SPI interface and an additional open-drain interrupt output. The devices include an analog output to monitor load conditions. The MAX15500/MAX15501 operate over the -40NC to +105NC temperature range. The devices are available in a 32-pin, 5mm x 5mm TQFN package. MAX15500/MAX15501 S S S S S S S S ±10V 0 to 10V 0 to 5V ±20mA 0 to 20mA 4 to 20mA Current Output Drives 0 to 1kI Voltage Output Drives Loads Down to 1kI HART Compliant 2ppm Gain Error Drift Over Temperature SPI Interface, with Daisy-Chain Capability Supports +4.096V (MAX15500) or +2.5V (MAX15501) Full-Scale Input Signals Extensive Error Reporting Short-Circuit and Overcurrent Protection Open-Circuit Detection Brownout Detection Overtemperature Protection Fast, 40µs Settling Time Ordering Information PART MAX15500GTJ+ MAX15501GTJ+ PIN-PACKAGE 32 TQFN-EP* 32 TQFN-EP* REFERENCE +4.096V +2.5V Applications Programmable Logic Controllers (PLCs) Distributed I/Os Embedded Systems Industrial Control and Automation Note: All devices are specified over the -40NC to +105NC operating temperature range. +Denotes a lead(Pb)-free/RoHS-compliant package. *EP = Exposed pad. SPI is a trademark of Motorola, Inc. Pin Configuration SENSEVN SENSERN AVDDO COMP 18 N.C. OUT AVSSO 17 16 15 14 N.C. AGND AIN REFIN AGND FSMODE FSSEL OUTDIS 13 12 11 10 9 1 SCLK 2 DIN 3 DOUT 4 READY 5 ERROR 6 DVDD 7 DGND 8 N.C. Simplified Block Diagram DVDD SCLK DIN DOUT CS1 CS2 READY AIN ERROR MON REFIN ERROR HANDLING BIDIRECTIONAL VOLTAGE DRIVER AVDD AVDDO TOP VIEW 24 SENSEVP 25 23 22 SENSERP 21 20 19 MAX15500 MAX15501 SPI INTERFACE BIDIRECTIONAL CURRENT DRIVER ERROR HANDLING OVERCURRENT PROTECTION AVDD 26 SENSERN SENSERP COMP OUT AGND 27 AVSS 28 MON 29 CS1 30 CS2 31 MAX15500 MAX15501 EP* + SENSEVP SENSEVN N.C. 32 FSMODE FSSEL AVSS AVSSO AGND DGND OUTDIS *EXPOSED PAD. TQFN _______________________________________________________________ Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. Industrial Analog Current/ Voltage-Output Conditioners MAX15500/MAX15501 ABSOLUTE MAXIMUM RATINGS AVDD to AGND ..................................................... -0.3V to +35V AVSS to AGND ...................................................... -35V to +0.3V AVDD to AVSS............................................................. 0 to +70V AVDD to AVDDO ........................................................... 0 to +4V AVSS to AVSSO............................................................ -4V to 0V DGND to AGND ................................................... -0.3V to +0.3V AVDD to DVDD......................................................... -6V to +35V DVDD to DGND .................................................... -0.3V to +6.0V CS1, CS2, SCLK, DIN, DOUT, READY, ERROR, FSMODE, MON, OUTDIS, FSSEL to DGND...................... -0.3V to +6.0V AIN, REFIN to AGND ............................................ -0.3V to +6.0V SENSEVP, SENSEVN, SENSERP, SENSERN to AGND the higher of -35V and (VAVSS - 0.3V) to the lower of (VAVDD + 0.3V) and +35V OUT, COMP to AGND .. the higher of -35V and (VAVSS - 0.3V) to the lower of (VAVDD + 0.3V) and +35V Maximum Current on Pin ............................................... ±100mA Continuous Power Dissipation (derate 34.5mW/NC above +70NC) 32-Pin TQFN (TA = +70NC, multilayer board) ......... 2758.6mW Operating Temperature Range ........................ -40NC to +105NC Storage Temperature Range............................ -65NC to +150NC Lead Temperature (soldering, 10s) ................................+300NC Soldering Temperature (reflow) ......................................+260NC 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 conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (VAVDD = +24V, VAVSS = -24V, VDVDD = 5.0V, CLOAD = 1nF, CCOMP = 0nF, VREFIN = 4.096V for the MAX15500, VREFIN = 2.5V for the MAX15501. All specifications for TA = -40NC to +105NC. Typical values are at TA = +25NC, unless otherwise noted.) PARAMETER POWER SUPPLY (Note 1) Analog Positive Supply Voltage Analog Negative Supply Voltage AVDD to AVDDO Voltage Difference AVSS to AVSSO Voltage Difference Digital Supply Voltage Analog Positive Supply Current Analog Negative Supply Current Digital Supply Current Analog Positive Standby Current Analog Negative Standby Current ANALOG INPUT (AIN, REFIN) Input Impedance Input Capacitance Analog Input Full Scale REFIN Full-Scale Input RIN CIN VAIN VREFIN FSSEL = DVDD, MAX15500 FSSEL = DGND, MAX15501 FSSEL = DVDD, MAX15500 FSSEL = DGND, MAX15501 4.0 2.4 4.0 2.4 10 10 4.096 2.5 4.096 2.5 4.2 2.6 4.2 2.6 kI pF V V VAVDD VAVSS VAVDDO VAVSSO VDVDD IAP IAN IDVDD ISTBYP ISTBYN IAP = IAVDD + IAVDDO, ILOAD = 0A IAN = IAVSS + IAVSSO, ILOAD = 0A VDVDD = 5V ISTBYP = IAVDD + IAVDDO, OUTDIS = DGND or software standby mode ISTBYN = IAVSS + IAVSSO, OUTDIS = DGND or software standby mode -7 5% overrange (FSMODE = DVDD) 20% overrange (FSMODE = DGND) 5% overrange (FSMODE = DVDD) 20% overrange (FSMODE = DGND) (Note 1) (Note 1) 2.7 5 -4.5 0.1 1 -0.5 0.4 15 18.5 -32.5 -32.5 24 24 -24 -24 2.5 2.5 5.25 7 32.5 32.5 -15 -18.5 V V V V V mA mA mA mA mA SYMBOL CONDITIONS MIN TYP MAX UNITS 2 ______________________________________________________________________________________ Industrial Analog Current/ Voltage-Output Conditioners ELECTRICAL CHARACTERISTICS (continued) (VAVDD = +24V, VAVSS = -24V, VDVDD = 5.0V, CLOAD = 1nF, CCOMP = 0nF, VREFIN = 4.096V for the MAX15500, VREFIN = 2.5V for the MAX15501. All specifications for TA = -40NC to +105NC. Typical values are at TA = +25NC, unless otherwise noted.) PARAMETER CURRENT OUTPUT (Note 2) Maximum Load Resistance Maximum Load Inductance Maximum Load Capacitance RLOAD LLOAD CLOAD VAVDD = +24V, VAVSS = -24V VAVDD = +32.5V, VAVSS = -32.5V CCOMP = 100nF (Note 3) CCOMP = 4.7nF To 0.1% accuracy, LLOAD = 20FH, CCOMP = 0nF To 0.1% accuracy, LLOAD = 1mH, CCOMP = 0.15nF Full-scale step from 0 to 20mA or -20mA to + 20mA, RLOAD = 750I To 0.1% accuracy, LLOAD = 10mH, CCOMP = 0.15nF To 0.01% accuracy, LLOAD = 20FH, CCOMP = 0nF To 0.01% accuracy, LLOAD = 10mH, CCOMP = 0.15nF To 0.1% accuracy, LLOAD = 20FH, CCOMP = 0nF To 0.1% accuracy, LLOAD = 1mH, CCOMP = 0.15nF 1% full-scale step, RLOAD = 750I To 0.1% accuracy, LLOAD = 10mH, CCOMP = 0.15nF To 0.01% accuracy, LLOAD = 20FH, CCOMP = 0nF To 0.01% accuracy, LLOAD = 10mH, CCOMP = 0.15nF Full-Scale Output Current IOUT VFSMODE = VDVDD VFSMODE = VDGND 750 1000 15 100 40 I mH FF SYMBOL CONDITIONS MIN TYP MAX UNITS MAX15500/MAX15501 500 500 60 600 Fs 20 Maximum Settling Time 100 100 40 200 Q21 Q24 mA _______________________________________________________________________________________ 3 Industrial Analog Current/ Voltage-Output Conditioners MAX15500/MAX15501 ELECTRICAL CHARACTERISTICS (continued) (VAVDD = +24V, VAVSS = -24V, VDVDD = 5.0V, CLOAD = 1nF, CCOMP = 0nF, VREFIN = 4.096V for the MAX15500, VREFIN = 2.5V for the MAX15501. All specifications for TA = -40NC to +105NC. Typical values are at TA = +25NC, unless otherwise noted.) PARAMETER Offset Error Offset-Error Drift 0.01% precision RSENSE, tested according to the ideal transfer functions shown in Table 8 No RSENSE drift INL (dIOUT/dVOUT), IOUT = 24mA, RLOAD = 750I to 0I, FSMODE = DGND, unipolar mode PSRR At DC, VAVDD = +24V to +32.5V, VAVSS = -24V to -32.5V, VAIN = VREFIN, unipolar mode, FSMODE = DVDD RSENSE shorted 0.1Hz to 10Hz At 1kHz 25 MAX15500 SYMBOL CONDITIONS VAIN = 5% of VREFIN (unipolar mode), VAIN = 50% of VREFIN (bipolar mode) MIN TYP Q0.1 Q5 Q0.1 Q0.51 %FS MAX15501 Q0.1 Q2 0.05 1.0 Q0.5 ppm/NC %FS FA/V MAX Q0.5 UNITS %FS ppm/NC Gain Error GE Gain-Error Drift Integral Nonlinearity Error Output Conductance Power-Supply Rejection Ratio Overcurrent Limit Output Current Noise Output Slew Rate Small-Signal Bandwidth Maximum OUT Voltage to AVDDO Minimum OUT Voltage to AVSSO VOLTAGE OUTPUT (RLOAD = 1kI) Minimum Resistive Load Maximum Capacitive Load 1.6 30 20 2.6 1.5 30 40 FA/V mA nARMS nA/√Hz mA/Fs kHz V V VAVDDO - VOUT VOUT - VAVSSO RLOAD CLOAD CCOMP = 4.7nF To 0.1% accuracy, load = 1kI in parallel with 1nF, CCOMP = 0nF 2.0 2.0 1 100 20 1000 kI FF Maximum Settling Time (FullScale Step) To 0.1% accuracy, load = 1kI in parallel with 1FF, CCOMP = 4.7nF To 0.01% accuracy, load = 1kI in parallel with 1nF, CCOMP = 0nF To 0.01% accuracy, load = 1kI in parallel with 1FF, CCOMP = 4.7nF Fs 30 1300 4 ______________________________________________________________________________________ Industrial Analog Current/ Voltage-Output Conditioners ELECTRICAL CHARACTERISTICS (continued) (VAVDD = +24V, VAVSS = -24V, VDVDD = 5.0V, CLOAD = 1nF, CCOMP = 0nF, VREFIN = 4.096V for the MAX15500, VREFIN = 2.5V for the MAX15501. All specifications for TA = -40NC to +105NC. Typical values are at TA = +25NC, unless otherwise noted.) PARAMETER SYMBOL CONDITIONS To 0.1% accuracy, load = 1kI in parallel with 1nF, CCOMP = 0nF Maximum Settling Time (1% Full-Scale Step) To 0.1% accuracy, load = 1kI in parallel with 1FF, CCOMP = 4.7nF To 0.01% accuracy, load = 1kI in parallel with 1nF, CCOMP = 0nF To 0.01% accuracy, load = 1kI in parallel with 1FF, CCOMP = 4.7nF Gain Error Gain-Error Drift FSMODE = DVDD Full-Scale Output Voltage VOUT FSMODE = DGND 5V range 10V range 5V range 10V range Tested according to the ideal transfer functions shown in Table 9 MIN TYP 10 300 Fs 20 600 Q0.1 Q2 5.25 10.5 6 12 Q0.1 Q2 INL PSRR At DC, VAVDD = +18.5V to +32.5V, VAVSS = -18.5V to -32.5V, VAIN = VREFIN 0.1Hz to 10Hz 1kHz 20 VAVDDO - VOUT VOUT - VAVSSO 0.05 30 16.3 250 1.5 30 2.0 2.0 45 Q0.5 %FS ppm/NC %FS FV/V FVRMS nV/√Hz V/Fs mA V V V Q0.5 %FS ppm/NC MAX UNITS MAX15500/MAX15501 Offset Error Offset-Error Drift Integral Nonlinearity Error Power-Supply Rejection Output-Voltage Noise Output-Voltage Slew Rate Short-Circuit Current Maximum OUT Voltage to AVDDO Minimum OUT Voltage to AVSSO VAIN = 5% of VREFIN (unipolar mode), VAIN = 50% of VREFIN (bipolar mode) _______________________________________________________________________________________ 5 Industrial Analog Current/ Voltage-Output Conditioners MAX15500/MAX15501 ELECTRICAL CHARACTERISTICS (continued) (VAVDD = +24V, VAVSS = -24V, VDVDD = 5.0V, CLOAD = 1nF, CCOMP = 0nF, VREFIN = 4.096V for the MAX15500, VREFIN = 2.5V for the MAX15501. All specifications for TA = -40NC to +105NC. Typical values are at TA = +25NC, unless otherwise noted.) PARAMETER OUTPUT MONITOR (MON) Current mode, see the Output Monitor section for VMON equations Voltage mode, see the Output Monitor section for VMON equations 3 V 3 35 +150 10 kI NC NC SYMBOL CONDITIONS MIN TYP MAX UNITS Maximum Output Voltage Output Resistance OVERTEMPERATURE DETECTION Overtemperature Threshold Overtemperature Threshold Hysteresis DIGITAL INPUTS (CS1, CS2, SCLK, DIN, OUTDIS, FSSEL, FSMODE) Input High Voltage Input Low Voltage Input Hysteresis Input Leakage Current Input Capacitance VIH VIL VIHYST IIN CIN ISINK = 4mA ISOURCE = 4mA DOUT only DOUT only VDVDD = 5.25V ISINK = 5.0mA VDVDD 0.5 VINPUT = 0V or VDVDD 0.7 x VDVDD V 0.3 x VDVDD 300 Q0.1 10 0.4 Q1.0 V mV FA pF V V Q0.1 15 Q150 0.4 Q0.1 15 Q1.0 Q10 FA pF mA V FA pF mA DIGITAL OUTPUT (DOUT, READY) Output Low Voltage VOL Output High Voltage Output Three-State Leakage Output Three-State Capacitance Output Short-Circuit Current DIGITAL INTERRUPT (ERROR) Interrupt Active Voltage Interrupt Inactive Leakage Interrupt Inactive Capacitance Interrupt Short-Circuit Current VOH IOZ COZ IOSS VINT IINTZ CINTZ IINTSS VDVDD = 2.7V 5 30 6 ______________________________________________________________________________________ Industrial Analog Current/ Voltage-Output Conditioners ELECTRICAL CHARACTERISTICS (continued) (VAVDD = +24V, VAVSS = -24V, VDVDD = 5.0V, CLOAD = 1nF, CCOMP = 0nF, VREFIN = 4.096V for the MAX15500, VREFIN = 2.5V for the MAX15501. All specifications for TA = -40NC to +105NC. Typical values are at TA = +25NC, unless otherwise noted.) PARAMETER TIMING CHARACTERISTICS Serial-Clock Frequency SCLK Pulse-Width High SCLK Pulse-Width Low CS_ Fall to SCLK Fall Setup Time SCLK Fall to CS_ Fall Hold Time DIN to SCLK Fall Setup Time DIN to SCLK Fall Hold Time SCLK Fall to DOUT Settle Time SCLK Fall to DOUT Hold Time SCLK Fall to DOUT Disable SCLK Fall to READY Fall CS_ Fall to DOUT Enable CS_ Rise to DOUT Disable CS_ Rise to READY Rise CS_ Pulse-Width High fSCLK tCH tCL tCSS tCSH tDS tDH tDOT tDOH tDOZ tCR tDOE tCSDOZ tCSR tCSW CLOAD = 20pF CLOAD = 0pF 14th SCLK deassertion (Note 6) 16th SCLK assertion, CLOAD = 0pF or 20pF Asynchronous assertion Asynchronous deassertion Asynchronous deassertion, CLOAD = 20pF 15 2 1 2 30 30 35 35 35 (Note 4) 40% duty cycle 60% duty cycle To 1st SCLK falling edge (Note 5) 0 20 20 15 0 15 0 30 20 MHz ns ns ns ns ns ns ns ns ns ns ns ns ns ns SYMBOL CONDITIONS MIN TYP MAX UNITS MAX15500/MAX15501 Note 1: Use diodes as shown in the Typical Operating Circuit/Functional Diagram to ensure a voltage difference of 2V to 3.5V from AVDD to AVDDO and from AVSS to AVSSO. Note 2: RLOAD = 750I. For the MAX15500, RSENSE = 48.7I for FSMODE = DVDD and RSENSE = 42.2I for FSMODE = DGND. For the MAX15501, RSENSE = 47.3I for FSMODE = DVDD and RSENSE = 41.2I for FSMODE = DGND. See the Typical Operating Circuit/Functional Diagram. Note 3: Condition at which part is stable. Note 4: The maximum clock speed for daisy-chain applications is 10MHz. Note 5: tCSH is applied to CS_ falling to determine the 1st SCLK falling edge in a free-running SCLK application. It is also applied to CS_ rising with respect to the 15th SCLK falling edge to determine the end of the frame. Note 6: After the 14th SCLK falling edge, the MAX15500/MAX15501 outputs are high impedance and DOUT data is ignored. _______________________________________________________________________________________ 7 Industrial Analog Current/ Voltage-Output Conditioners MAX15500/MAX15501 Typical Operating Characteristics (VAVDD = +24V, VDVDD = +5V, VAVSS = -24V, CLOAD = 1nF, 5% overrange mode, unipolar current output or bipolar voltage-output mode, VREFIN = +4.096V, TA = +25NC, unless otherwise specified.) SUPPLY CURRENT vs. TEMPERATURE MAX15500 toc01 VOLTAGE-MODE OUTPUT SLEW RATE vs. TEMPERATURE MAX15500 toc02 CURRENT-MODE OUTPUT SLEW RATE vs. TEMPERATURE RLOAD = 750I CLOAD = 1FF MAX15500 toc03 10 8 6 SUPPLY CURRENT (mA) 4 2 0 -2 -4 -6 -8 10 NO LOAD 3.0 NO LOAD 2.5 OUTPUT SLEW RATE (V/Fs) 2.0 1.5 1.0 0.5 0 3.0 2.5 2.0 1.5 1.0 0.5 0 IAVDD IAVSS -40 -25 -10 5 20 35 50 65 80 95 105 TEMPERATURE (NC) -40 -25 -10 5 20 35 50 65 80 95 105 TEMPERATURE (NC) OUTPUT SLEW RATE (mA/Fs) -40 -25 -10 5 20 35 50 65 80 95 105 TEMPERATURE (NC) VOLTAGE-MODE OUTPUT NOISE vs. FREQUENCY MAX15500 toc04 CURRENT-MODE OUTPUT NOISE vs. FREQUENCY 900 OUTPUT NOISE (FV/ Hz) 800 700 600 500 400 300 200 100 0 VAIN = 200mV UNIPOLAR CURRENT MODE (0 to 20mA) MAX15500 toc05 1000 900 OUTPUT NOISE (FV/ Hz) 800 700 600 500 400 300 200 100 0 10 VAIN = 0V UNIPOLAR VOLTAGE MODE (0 to 5V) 1000 100 1k FREQUENCY (Hz) 10k 10 100 1k FREQUENCY (Hz) 10k DIGITAL FEEDTHROUGH MAX15500 toc06 VOLTAGE-MODE PSRR vs. SUPPLY VOLTAGE 90 80 PSRR (FV/V) 70 60 50 40 30 20 10 0 24 26 28 30 SUPPLY VOLTAGE (V) 32 VAIN = 4.096V MAX15500 toc07 100 SCLK 2V/div VOUT (AC-COUPLED) 1mV/div SCLK = DIN SCLK = 1MHz CS_ = HIGH VAIN = 0.5 x VREFIN 400ns/div 8 ______________________________________________________________________________________ Industrial Analog Current/ Voltage-Output Conditioners Typical Operating Characteristics (continued) (VAVDD = +24V, VDVDD = +5V, VAVSS = -24V, CLOAD = 1nF, 5% overrange mode, unipolar current output or bipolar voltage-output mode, VREFIN = +4.096V, TA = +25NC, unless otherwise specified.) CURRENT-MODE PSRR vs. SUPPLY VOLTAGE 0.9 0.8 0.7 PSRR (FA/V) 0.6 0.5 0.4 0.3 0.2 0.1 0 24 25 26 27 28 29 30 SUPPLY VOLTAGE (V) 31 32 40Fs/div MAX15500 toc08 MAX15500/MAX15501 LOAD TRANSIENT (VOLTAGE MODE) MAX15500 toc09 1.0 IOUT 10mA/div OmA VOUT (AC-COUPLED) 20mV/div LOAD TRANSIENT (CURRENT MODE) MAX15500 toc10 FULL-SCALE OUTPUT VOLTAGE vs. TEMPERATURE FULL-SCALE OUTPUT VOLTAGE (ppm/NC) 16 12 8 4 0 -4 -8 -12 -16 -20 -40 -25 -10 5 20 35 50 65 80 95 TEMPERATURE (NC) VAIN = 4.096V MAX15500 toc11 MAX15500 toc13 20 VOUT 10V/div O IOUT 10mA/div 0mA 40Fs/div OUTPUT CURRENT DRIFT vs. TEMPERATURE VAIN = 4.096V MAX15500 toc12 STANDBY SUPPLY CURRENT vs. TEMPERATURE 2.0 1.5 SUPPLY CURRENT (mA) 1.0 0.5 0 -0.5 -1.0 -1.5 IAVSS IAVDD NO LOAD 10 OUTPUT CURRENT DRIFT (ppm/NC) 6 2 -2 -6 -10 -2.0 -40 -25 -10 5 20 35 50 65 80 95 TEMPERATURE (NC) -40 -25 -10 5 20 35 50 65 80 95 TEMPERATURE (NC) _______________________________________________________________________________________ 9 Industrial Analog Current/ Voltage-Output Conditioners MAX15500/MAX15501 Typical Operating Characteristics (continued) (VAVDD = +24V, VDVDD = +5V, VAVSS = -24V, CLOAD = 1nF, 5% overrange mode, unipolar current output or bipolar voltage-output mode, VREFIN = +4.096V, TA = +25NC, unless otherwise specified.) WAKEUP FROM STANDBY (VOLTAGE MODE) WAKEUP FROM STANDBY (CURRENT MODE) MAX15500 toc15 GAIN vs. FREQUENCY (HART COMPLIANT) BIPOLAR CURRENT MODE MAX15500 toc16 MAX15500 toc14 0 -4 -8 -12 -16 -20 VAIN = 40mVP-P 10 100 1k 10k FREQUENCY (Hz) UNIPOLAR CURRENT MODE 0V 5V/div VOUT 0V FULL-SCALE INPUT BIPOLAR VOLTAGE MODE 5% OVERRANGE 50Fs/div IOUT 10mA/div GAIN (dB) 2V/div OUTDIS OUTDIS 2V/div 40Fs/div 100k SMALL-SIGNAL STEP RESPONSE (CURRENT MODE) MAX15500 toc17 SMALL-SIGNAL STEP RESPONSE (VOLTAGE MODE) MAX15500 toc18 OUTPUT SHORT-CIRCUIT CURRENT vs. TEMPERATURE 34.5 SHORT-CIRCUIT CURRENT (mA) VAIN = 4.096V MAX15500 toc19 MAX15500 toc22 35.0 34.0 33.5 33.0 32.5 32.0 31.5 31.0 30.5 30.0 VAIN 20mV/div VAIN (AC-COUPLED) 50mV/div IOUT 100FA/div VOUT (AC-COUPLED) 100mV/div 5Fs/div 1Fs/div -40 -25 -10 5 20 35 50 65 80 95 TEMPERATURE (NC) VOLTAGE-MODE MON TRANSFER CURVE vs. OUTPUT CURRENT MAX15500 toc20 CURRENT-MODE MON TRANSFER CURVE vs. OUTPUT VOLTAGE MAX15500 toc21 VOLTAGE-MODE MAXIMUM OUT TO AVDDO VOLTAGE vs. TEMPERATURE 1.0 MAXIMUM INTERNAL VOLTAGE DROP (V) 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 -40 -25 -10 5 20 35 50 65 80 95 TEMPERATURE (NC) VAIN = 4.096V 3.0 2.6 2.2 1.8 1.4 1.0 0 1 2 3 4 67 IOUT (mA) 5 8 VAIN = 4.096V NO LOAD ON MON 3.0 2.8 2.6 2.4 2.2 2.0 1.8 1.6 1.4 1.2 1.0 VAIN = 4.096V NO LOAD ON MON MON (V) MON (V) 9 10 11 0 4 8 VOUT (V) 12 16 10 _____________________________________________________________________________________ Industrial Analog Current/ Voltage-Output Conditioners Typical Operating Characteristics (continued) (VAVDD = +24V, VDVDD = +5V, VAVSS = -24V, CLOAD = 1nF, 5% overrange mode, unipolar current output or bipolar voltage-output mode, VREFIN = +4.096V, TA = +25NC, unless otherwise specified.) CURRENT-MODE OUTPUT CONDUCTANCE vs. OUTPUT VOLTAGE MAX15500 toc23 MAX15500/MAX15501 LARGE-SIGNAL SETTLING TIME (VOLTAGE MODE, RISING EDGE) MAX15500 toc24 LARGE-SIGNAL SETTLING TIME (VOLTAGE MODE, FALLING EDGE) MAX15500 toc25 2.0 1.8 OUTPUT CONDUCTANCE (FA/V) 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0 0 2 4 6 8 10 12 OUTPUT VOLTAGE (V) 14 RL = 1kI VAIN 5V/div VOUT 5V/div RL = 1kI VAIN 5V/div 0 VOUT 5V/div CL = 1nF, CCOMP = 0nF CL = 47nF, CCOMP = 0nF CL = 470nF, CCOMP = 4.7nF CL = 470nF, CCOMP = 4.7nF CL = 47nF, CCOMP = 0nF CL = 1nF, CCOMP = 0nF 16 100Fs/div 100Fs/div LARGE-SIGNAL SETTLING TIME (VOLTAGE MODE, RISING EDGE) MAX15500 toc26 LARGE-SIGNAL SETTLING TIME (VOLTAGE MODE, RISING EDGE) MAX15500 toc27 LARGE-SIGNAL SETTLING TIME (CURRENT MODE, RISING EDGE) MAX15500 toc28 RL = 1kI VAIN 5V/div CL = 1FF, CCOMP = 4.7nF CL = 10FF, CCOMP = 4.7nF VOUT CL = 100FF, CCOMP = 4.7nF VOUT 5V/div VAIN 5V/div CL = 100FF, CCOMP = 4.7nF CL = 10FF, CCOMP = 4.7nF CL = 1FF, CCOMP = 4.7nF RL = 1kI VAIN 5V/div LL = 22FH, CCOMP = 0nF RL = 750I LL = 220FH, CCOMP = 0nF LL = 1mH, CCOMP = 1nF IOUT 4mA/div 10ms/div 10ms/div 200Fs/div LARGE-SIGNAL SETTLING TIME (CURRENT MODE, FALLING EDGE) MAX15500 toc29 LARGE-SIGNAL SETTLING TIME (CURRENT MODE, RISING EDGE) MAX15500 toc30 LARGE-SIGNAL SETTLING TIME (CURRENT MODE, FALLING EDGE) MAX15500 toc31 RL = 750I VAIN 5V/div LL = 22FH, CCOMP = 0nF LL = 220FH, CCOMP = 0nF LL = 1mH, CCOMP = 1nF IOUT 4mA/div VAIN 5V/div LL = 22FH, CCOMP = 0.15nF RL = 20I VAIN RL = 20I LL = 220FH, CCOMP = 0.47nF LL = 1mH, CCOMP = 1nF IOUT 4mA/div IOUT 4mA/div LL = 1mH, CCOMP = 1nF LL = 220FH, CCOMP = 0.47nF LL = 22FH, CCOMP = 0.15nF 20Fs/div 200Fs/div 20Fs/div ______________________________________________________________________________________ 11 Industrial Analog Current/ Voltage-Output Conditioners MAX15500/MAX15501 Typical Operating Characteristics (continued) (VAVDD = +24V, VDVDD = +5V, VAVSS = -24V, CLOAD = 1nF, 5% overrange mode, unipolar current output or bipolar voltage-output mode, VREFIN = +4.096V, TA = +25NC, unless otherwise specified.) LARGE-SIGNAL SETTLING TIME (CURRENT MODE, RISING EDGE) MAX15500 toc32 LARGE-SIGNAL SETTLING TIME (CURRENT MODE, FALLING EDGE) MAX15500 toc33 LARGE-SIGNAL SETTLING TIME (CURRENT MODE, RISING EDGE) MAX15500 toc34 RL = 750I VAIN 5V/div VAIN 5V/div RL = 750I VAIN 5V/div LL = 80mH, CCOMP = 470nF LL = 50mH, CCOMP = 100nF LL = 10mH, CCOMP = 10nF IOUT 4mA/div IOUT 4mA/div LL = 80mH, CCOMP = 470nF RL = 20I LL = 10mH, CCOMP = 10nF LL = 50mH, CCOMP = 100nF LL = 50mH, CCOMP = 100nF LL = 80mH, CCOMP = 470nF LL = 10mH, CCOMP = 10nF IOUT 4mA/div 100ms/div 100ms/div 10ms/div LARGE-SIGNAL SETTLING TIME (CURRENT MODE, FALLING EDGE) MAX15500 toc35 CURRENT-MODE INL MAX15500 toc36 VOLTAGE-MODE INL 0.03 0.02 INL (%FS) 0.01 0 -0.01 -0.02 -0.03 -0.04 MAX15500 toc37 RL = 20I VAIN 20V/div LL = 50mH, CCOMP = 100nF LL = 10mH, CCOMP = 10nF IOUT 4mA/div INL (%FS) LL = 80mH, CCOMP = 470nF 0.04 0.03 0.02 0.01 0 -0.01 -0.02 -0.03 -0.04 0.04 10ms/div 0 0.6 1.2 1.8 2.4 VAIN (V) 3.0 3.6 4.2 0 0.6 1.2 1.8 2.4 VAIN (V) 3.0 3.6 4.2 VOLTAGE-MODE SHORT-CIRCUIT DETECTION CURRENT-MODE OPEN-CIRCUIT DETECTION MAX15500 toc38 MAX15500 toc39 50mA/div IOUT 0mA 50mA/div IOUT 0mA ERROR ERROR 2V/div 2V/div 100ms/div 100ms/div 12 _____________________________________________________________________________________ Industrial Analog Current/ Voltage-Output Conditioners Pin Description PIN 1 2 3 NAME SCLK DIN DOUT FUNCTION SPI Clock Input. Activate SCLK only when CS_ is low to minimize noise coupling. SPI Data Input. Data is clocked into the serial interface on the falling edge of SCLK. SPI Data Output. Data transitions at DOUT on the falling edge of SCLK. DOUT is high impedance when either CS1 or CS2 is high. Active-Low Device Ready Output. READY is an active-low output that goes low when the device successfully completes processing an SPI data frame. READY returns high at the next rising edge of CS_. In daisy-chain applications, the READY output typically drives the CS_ input of the next device in the chain or a GPIO of a microcontroller. Active-Low Flag Output. ERROR is an open-drain output that pulls low when output short circuit, output open circuit, overtemperature, or brownout conditions occur. ERROR typically drives an interrupt input of a microcontroller. The ERROR output is cleared after the internal error register is read through the SPI interface. Connect a 10kΩ pullup resistor from ERROR to DVDD. Digital Power-Supply Voltage Input. Apply either a 3V or 5V nominal voltage supply to DVDD. DVDD powers the digital portion of the MAX15500/MAX15501. Bypass DVDD to DGND with a 0.1FF capacitor as close as possible to the device. Digital Ground No Connection. Not internally connected. Active-Low Output Disable Input. OUTDIS is an active-low logic input that forces the analog output to 0A or 0V and puts the device in standby mode when connected to DGND. Connect OUTDIS to DVDD for normal operation. Full-Scale Select Input. Connect FSSEL to DVDD for the MAX15500 when applying a +4.096V reference at REFIN. Connect FSSEL to DGND for the MAX15501 when applying a +2.50V reference at REFIN. Overrange Mode Select Input. Connect FSMODE to DVDD to set the output voltage to 105%FS when the input voltage is equal to the full-scale value. Connect FSMODE to DGND to set the output voltage to 120%FS when the input voltage is equal to the full-scale value. FSMODE has no effect in current mode. Analog Ground Reference Voltage Input. Connect REFIN to an external +4.096V reference for the MAX15500 or +2.5V reference for the MAX15501. REFIN is used to set the offset for unipolar and bipolar modes. Analog Signal Input. The analog input signal range at AIN is from 0V to the nominal full scale of +4.096V for the MAX15500 and +2.5V for the MAX15501. Negative Output Driver Supply Voltage Input. AVSSO provides power to the driver output stage. Bypass AVSSO to AVSS with a 0.1FF capacitor. Use diodes as shown in the Typical Operating Circuit/Functional Diagram to ensure a voltage difference of 2V to 3.5V between AVSS and AVSSO. Output Amplifier Compensation Feedback Node. Connect a compensation capacitor from COMP to OUT. See Table 10 for the recommended compensation capacitor values. MAX15500/MAX15501 4 READY 5 ERROR 6 7 8, 16, 24, 32 9 DVDD DGND N.C. OUTDIS 10 FSSEL 11 FSMODE 12, 15, 27 13 14 AGND REFIN AIN 17 AVSSO 18 COMP ______________________________________________________________________________________ 13 Industrial Analog Current/ Voltage-Output Conditioners MAX15500/MAX15501 Pin Description (continued) PIN 19 NAME OUT FUNCTION Analog Output. The analog voltage or current output range at OUT is programmable. See Tables 1 to 4 for possible output range settings. Positive Output Driver Supply Voltage Input. AVDDO provides power to the driver output stage. Bypass AVDDO to AVDD with a 0.1FF capacitor. Use diodes as shown in the Typical Operating Circuit/Functional Diagram to ensure a voltage difference of 2V to 3.5V between AVDD and AVDDO. Sense Resistor Positive Connection. See the Typical Operating Circuit/Functional Diagram for the typical connection. Sense Resistor Negative Connection. See the Typical Operating Circuit/Functional Diagram for the typical connection. Kelvin Sense Voltage Negative Input. See the Typical Operating Circuit/Functional Diagram for the typical connection. Kelvin Sense Voltage Positive Input. See the Typical Operating Circuit/Functional Diagram for the typical connection. Positive Analog Supply Voltage Input. Bypass AVDD to AGND with a 0.1FF capacitor. Negative Analog Supply Voltage Input. Bypass AVSS to AGND with a 0.1FF capacitor. Load Monitoring Output. MON provides an analog 0 to 3V output. See the Output Monitor section. Active-Low SPI Chip-Select Input 1. See the SPI Interface section. Active-Low SPI Chip-Select Input 2. See the SPI Interface section. Exposed Pad. Internally connected to AVSS. Connect to AVSS. Connect to a large copper area to maximize thermal performance. Do not connect ground or signal lines through EP. 20 AVDDO 21 22 23 25 26 28 29 30 31 — SENSERP SENSERN SENSEVN SENSEVP AVDD AVSS MON CS1 CS2 EP 14 _____________________________________________________________________________________ Industrial Analog Current/ Voltage-Output Conditioners Typical Operating Circuit/Functional Diagram MAX15500/MAX15501 24V 5V 0.1FF 0.1FF 0.1FF AVDD AVDDO DVDD DAC AIN 10kI SENSEVP SENSERP PGA COMP OUT SENSERN SENSEVN OFFSET GENERATOR OUTPUT STAGE WRITE SCLK CS FC READ DIN SCLK CS1 CS2 DOUT DVDD POR SPI INTERFACE/ LOGIC I/O BROWNOUT TEMP MONITOR AGND DGND 0.1FF 0.1FF AVSS MON CCOMP RSENSE CABLE1 2.5V/4.096V REF REFIN 10kI CABLE2 RLOAD CABLE3 CLOAD ADC MAX15500 MAX15501 AVSSO OUTDIS FSSEL* INT GPIO ERROR READY DVDD FSMODE -24V *FSSEL IS CONNECTED TO DGND FOR THE MAX15501. ______________________________________________________________________________________ 15 Industrial Analog Current/ Voltage-Output Conditioners MAX15500/MAX15501 Detailed Description The MAX15500/MAX15501 output a programmable current up to Q24mA or a voltage up to Q12V proportional to a control signal at AIN. The devices operate from a dual 15V to 32.5V supply. The control voltage applied at AIN is typically supplied by an external DAC with an output voltage range of 0 to 4.096V for the MAX15500 and 0 to 2.5V for the MAX15501. The MAX15500/MAX15501 are capable of both unipolar and bipolar current and voltage outputs. In current mode, the devices produce currents of -1.2mA to +24mA or -24mA to +24mA. In voltage mode, the devices produce voltages of -0.3V to +6V, -0.6V to +12V, or Q12V. To allow for overrange and underrange capability in unipolar mode, the transfer function of the MAX15500/MAX15501 is offset such that when the voltage at AIN is 5% of full scale, IOUT is 0mA and VOUT is 0V. Once VAIN attains full scale, VOUT or IOUT becomes full scale +5% or +20% depending on the state of FSMODE. The MAX15500/MAX15501 are protected against overcurrent and short-circuit conditions when OUT goes to ground or a voltage up to Q32.5V. The devices also monitor for overtemperature and supply brownout conditions. The supply brownout threshold is programmable between ±10V and ±24V in 2V increments. The MAX15500/MAX15501 are programmed through an SPI interface with daisy-chain capability. A device ready logic output (READY) and two device select inputs (CS1 and CS2) facilitate a daisy-chain arrangement for multiple device applications. The MAX15500/MAX15501 provide extensive error reporting of short-circuit, open-circuit, brownout, and overtemperature conditions through the SPI interface and an additional open-drain interrupt output (ERROR). The MAX15500/MAX15501 include an analog 0 to 3V output (MON) to monitor the load condition at OUT. The MAX15500/MAX15501 support two output modes: current and voltage. Each mode has different full-scale output values depending on the state of FSMODE as detailed in Tables 1 to 4 and Figures 1 and 2. Use the device configuration register in Table 6 to select the desired voltage or current output range. During startup, the MAX15500/MAX15501 output is set to zero and all register bits are set to zero. The devices remain in standby mode until they are configured through the SPI interface. The input voltage full-scale level is selectable between 2.5V and 4.096V using logic input FSSEL. The MAX15500 is specified for a 0 to 4.096V input voltage range, while the MAX15501 is specified for a 0 to 2.500V input voltage range. Connect FSSEL to DVDD to set the input range to 0 to 4.096V for the MAX15500. Connect FSSEL to DGND to set the input range to 0 to 2.500V for the MAX15501. Analog Section Startup Input Voltage Range Table 1. Output Values for FSMODE = DVDD, Unipolar 5% Overrange OUTPUT RANGE 0 to 20mA (4mA to 20mA) 0 to 5V 0 to 10V OUTPUT VALUES VAIN = 5%FS 0mA 0V 0V VAIN = FS 21mA 5.25V 10.5V Table 3. Output Values for FSMODE = DVDD, Bipolar 5% Overrange OUTPUT RANGE Q20mA Q10V OUTPUT VALUES VAIN = 0V -21mA -10.5V VAIN = FS +21mA +10.5V Table 2. Output Values for FSMODE = DGND, Unipolar 20% Overrange OUTPUT RANGE 0 to 20mA (4mA to 20mA) 0 to 5V 0 to 10V 16 OUTPUT VALUES VAIN = 5%FS 0mA 0V 0V VAIN = FS 24mA 6V 12V Table 4. Output Values for FSMODE = DGND, Bipolar 20% Overrange OUTPUT RANGE Q20mA Q10V OUTPUT VALUES VAIN = 0V -24mA -12V VAIN = FS +24mA +12V _____________________________________________________________________________________ Industrial Analog Current/ Voltage-Output Conditioners The MON output provides an analog voltage signal proportional to the output voltage in current mode and proportional to the output current in voltage mode. Use this signal to measure the system load presented to the output. The full-scale signal on MON is 3V with a typical accuracy of 10%. The signal range is typically 1.5V to 3V in unipolar mode and 0 to 3V in bipolar mode. In current mode, the MAX15500/MAX15501 program IOUT and monitor the voltage at SENSERN. VMON = 1.425V + (VSENSERN/20) RLOAD = ((VMON - 1.425V) x 20)/IOUT(PROGRAMMED) In voltage mode, the MAX15500/MAX15501 program VOUT and monitor IOUT. VMON = 1.521V + 62.4 x ILOAD RLOAD = VOUT(PROGRAMMED)/((VMON - 1.521V)/62.4) Many industrial control systems require error detection and handling. The MAX15500/MAX15501 provide extensive error status reporting. An open-drain interrupt flag output, ERROR, pulls low when an error condition is detected. An error register stores the error source. Reading the error register once Output Short Circuit Output Monitor resets the ERROR pin but not the error register itself, allowing the system to determine the source of the error and take steps to fix the error condition. After the error condition has been fixed, read the error register for the second time to allow the device to clear the error register. Read the error register for the third time to verify if the error register has been cleared. If another error occurs after the first read, ERROR goes low again. More information on reading and clearing the error register is described in the SPI Interface section. When an output short-circuit or output open-load error occurs and disappears before the error register is read, the intermittent bit is set in the error register. The intermittent bit does not assert for brownout and overtemperature error conditions. Error Conditions The output short-circuit error bit asserts when the output current exceeds 30mA (typ) for longer than 260ms. In current mode, this error occurs when the sense resistor is shorted and the sense voltage is not equal to 0V. In voltage mode, this error occurs when the load is shorted to the supply or ground. The short-circuit error activates the intermittent bit in the error register if the error goes away before the error register is read. MAX15500/MAX15501 Error Handling VOUT OR IOUT VOUT OR IOUT FS + 20% FS + 5% FS + 20% FS FS + 5% FS FSMODE = DGND FSMODE = DGND VAIN 50%FS FSMODE = DVDD FSMODE = DVDD VAIN 5%FS FS -FS -FS - 5% -FS - 20% FS Figure 1. Unipolar Transfer Function Figure 2. Bipolar Transfer Function ______________________________________________________________________________________ 17 Industrial Analog Current/ Voltage-Output Conditioners MAX15500/MAX15501 Output Open Load The open-circuit error bit activates when VOUT is within 30mV of AVDDO or AVSSO and there is no short-circuit current in current mode for longer than 260ms. This error activates the intermittent bit in the error register if the error goes away before the error register is read. Internal Overtemperature The MAX15500/MAX15501 enter standby mode if the die temperature exceeds +150NC and the overtemperature protection is enabled as shown in Table 6. When the die temperature cools down below +140NC, the error register must be read back twice to resume normal operation. The devices provide a 10NC hysteresis. Brownout The brownout-error bit activates when the supply voltage (VAVDD or VAVSS) falls below the brownout threshold. The threshold is programmable between Q10V to Q24V in 2V steps. See Table 6 for details. The MAX15500/ MAX15501 provide a 2% hysteresis for the brownout threshold. The accuracy of the threshold is typically within 10%. During power-up, ERROR can go low and the brownout register is set. Users need to read out the error register twice to clear all the error register bits and reset ERROR to high. Output Protection The MAX15500/MAX15501 supply inputs (AVDD, AVDDO, AVSS, and AVSSO) and sense inputs (SENSERN, SENSERP, SENSEVN, and SENSEVP) are protected against voltages up to Q35V with respect to AGND. See the Typical Operating Circuit/Functional Diagram for the recommended supply-voltage connection. SPI Interface Standard SPI Implementation The MAX15500/MAX15501 SPI interface supports daisychaining. Multiple MAX15500/MAX15501 devices can be controlled from a single 4-wire SPI interface. The MAX15500/MAX15501 feature dual CS_ inputs and an added digital output, READY, that signals when the devices finish processing the SPI frame. CS1 and CS2 are internally OR-ed. Pull both CS1 and CS2 to logic-low to activate the MAX15500/MAX15501. For a daisy-chained application, connect the CS1 input of all of the devices in the chain to the CS driver of the microcontroller. Connect the CS2 input of the first device to ground or to the CS driver of the microcontroller. Connect CS2 of the remaining devices to the READY output of the preceding device in the chain. The READY output of the last device in the chain indicates when all slave devices in the chain are configured. Connect the READY output of the last device in the chain to the microcontroller. Use the open-drain ERROR output as a wired-OR interrupt. See Figures 3 to 6. TO OTHER CHIPS/CHAINS FC RPULLUP CSn MAX15500 MAX15501 CS2 CS1 SCLK DIN DOUT ERROR READY CS1 CS SCLK DWRITE DREAD INT MONITOR OPTIONAL CONNECTION Figure 3. Single Connection (Compatible with Standard SPI) 18 _____________________________________________________________________________________ Industrial Analog Current/ Voltage-Output Conditioners MAX15500/MAX15501 TO OTHER CHIPS/CHAINS FC RPULLUP CSn MAX15500 MAX15501 CS2 CS1 SCLK DIN DOUT ERROR READY CS1 CS SCLK DWRITE DREAD INT MONITOR OPTIONAL CONNECTION Figure 4. Alternate Single Connection (Compatible with Standard SPI) TO OTHER CHIPS/CHAINS FC RPULLUP CSn MAX15500 MAX15501 CS2 CS1 SCLK DIN DOUT ERROR READY CS1 CS SCLK DWRITE DREAD INT MONITOR MAX15500 MAX15501 CS2 CS1 SCLK DIN DOUT ERROR READY MAX15500 MAX15501 CS2 CS1 SCLK DIN DOUT ERROR READY OPTIONAL CONNECTION Figure 5. Daisy-Chain Connection (Compatible with Standard SPI) ______________________________________________________________________________________ 19 Industrial Analog Current/ Voltage-Output Conditioners MAX15500/MAX15501 TO OTHER CHIPS/CHAINS RPULLUP CSn FC MAX15500 MAX15501 CS2 CS1 SCLK DIN DOUT ERROR READY CS1 CS SCLK DWRITE DREAD INT MAX15500 MAX15501 CS2 CS1 SCLK DIN DOUT ERROR READY SPI DEVICE CS SCLK DIN DOUT Figure 6. Daisy-Chain Terminating (Compatible with Standard SPI) Modified SPI Interface Description The SCLK, DIN, and DOUT of the MAX15500/MAX15501 assume standard SPI functionality. While the basic function of the MAX15500/MAX15501 CS_ inputs is similar to the standard SPI interface protocol, the management of the CS_ input within the chain is modified. When both CS_ inputs are low, the MAX15500/MAX15501 assume control of the DOUT line and continue to control the line until the data frame is finished and READY goes low (Figure 9). Once a complete frame is processed and the READY signal is issued, the devices do not accept any data from DIN, until either CS1 or CS2 rises and returns low. A new communication cycle is initiated by a subsequent falling edge on CS1 or CS2. When either CS1 or CS2 is high, the MAX15500/MAX15501 SPI interface deactivates, DOUT returns to a high-impedance mode, READY (if active) clears, and any partial frames not yet processed are ignored. READY asserts once a valid frame is processed allowing the next device in the chain to begin processing the subsequent frame. A valid frame consists of 16 SCLK cycles following the falling edge of CS_. Once READY asserts, it remains asserted until either CS_ rises, completing the programming of the chain. 20 _____________________________________________________________________________________ Industrial Analog Current/ Voltage-Output Conditioners The MAX15500/MAX15501 relinquish control of DOUT once the devices process the frame(s). DOUT remains high impedance when the SPI interface continues to hold CS_ low beyond the required frame(s). Install a pullup/ puldown resistor at the DOUT line to maintain the desired state when DOUT goes high impedance. Single Device SPI Connection For applications using a single MAX15500 or MAX15501, connect both CS1 and CS2 inputs to the device-select driver of the host microcontroller. Alternatively, connect one of the CS_ inputs to the device-select driver of the host microcontroller and the other CS_ to DGND. Both methods allow standard SPI interface operation. See Figures 3 and 4. Daisy-Chain SPI Connection The MAX15500/MAX15501-modified SPI interface allows a single SPI master to drive multiple devices in a daisychained configuration, saving additional SPI channels for other devices and saving cost in isolated applications. Figure 5 shows multiple MAX15500/MAX15501 devices connected in a daisy chain. The chain behaves as a single device to the microcontroller in terms of timing with an expanded instruction frame requiring 16 SCLK cycles per device for complete programming. No timing parameters are affected by the READY propagation as all devices connect to the microcontroller chip-select through the CS1 inputs. A chain of MAX15500/MAX15501 devices can be terminated with any standard SPI-compatible single device without a READY output. The MAX15500/MAX15501 portion of the chain continues to display timing parameters comparable to a single device. See Figure 6. When using the MAX15500/MAX15501 with mixed chains, the connections could require some modification to accommodate the interfaces of the additional devices in the chain. Construct the daisy chain as shown in Figure 7 when using devices with similar READY outputs but without dual CS_ inputs such as the MAX5134 quad 16-bit DAC. The chain is subject to timing relaxation for parameters given with respect to CS_ rising edges to accommodate READY propagation to and through consecutive MAX5134 devices. The chain can begin and terminate with either device type. Each MAX5134 or MAX15500/MAX15501 device in the chain could be replaced by a subchain of similar devices. If the chain is terminated with a standard SPI device, omit the optional connection from READY to the monitor input on the microcontroller. The MAX15500/ MAX15501 portion of the chain continues to display timing parameters comparable to a single device. SPI Digital Specifications and Waveforms Figures 8, 9, and 10 show the operation of the modified SPI interface. The minimum programming operation typically used in single device applications is 16 SCLK periods, the minimum for a valid frame. This cycle can also represent the operation of the final device in a chain. The extended programming operation is typically used for devices in daisy-chained applications. In this case, READY drives the chip-select input of the subsequent device in the chain. The next device in the chain begins its active frame on the 16th SCLK falling edge in response to READY falling (latching DIN[13] on the 17th SCLK falling edge, if present). Aborted SPI Operations Driving a CS_ input high before a valid SPI frame is transmitted to the device can cause an erroneous command. Avoid driving CS_ high before a valid SPI frame is transmitted to the device. See Figures 9 and 10 for valid SPI operation timing. SPI Operation Definitions Input data bits DIN[13:11] represent the SPI command address while DIN[9:0] represent the data written to or read from the command address. The command address directs subsequent input data to the proper internal register for setting up the behavior of the device and selects the correct status data for readback through DOUT. Command address 0h points to a no-op command and does not impact the operation of the device. DOUT is active during this operation and reads back 00h. Command address 1h points to the configuration register used to program the MAX15500/MAX15501. Device configuration takes effect following the 14th SCLK falling edge. DOUT activates and remains low during this operation. Command addresses 4h and 5h point to readback commands of the MAX15500/MAX15501. Readback commands provide configuration and error register status through DOUT[9:0] and do not affect the internal operation of the device. Command addresses 2h, 3h, 6h, and 7h are reserved for future use. Table 5 shows the list of commands. Device Configuration Operation Table 6 shows the function of each bit written to the configuration register 1h. Table 7 shows the data readback registers. MAX15500/MAX15501 ______________________________________________________________________________________ 21 Industrial Analog Current/ Voltage-Output Conditioners MAX15500/MAX15501 TO OTHER CHIPS/CHAINS FC RPULLUP CSn MAX15500 MAX15501 CS2 CS1 SCLK DIN DOUT ERROR READY CS1 CS SCLK DWRITE DREAD INT MONITOR MAX15500 MAX15501 CS2 CS1 SCLK DIN DOUT ERROR READY MAX5134 CS SCLK DIN READY OPTIONAL CONNECTION Figure 7. Mixed MAX15500/MAX15501 and MAX5134 Daisy-Chain Connections ERROR REGISTER UPDATED, ERROR RE-EVALUATED ACTIVE FRAME DIN X DIN13 DIN12 DIN11 DIN10 tDS SCLK tCSH DOUT Z tDOE CS_ 1 tCSS 2 3 4 5 DIN9 DIN8 tCH 6 7 tCH 8 tCL DIN7 DIN6 tCP 9 tDOH 10 11 12 tDOT DIN5 DIN4 DIN3 DIN2 COMMAND EXECUTED DIN1 DIN0 X X X 13 tDOZ 14 15 16 X HIGH-Z DOUT9 DOUT8 DOUT7 DOUT6 DOUT5 DOUT4 DOUT3 DOUT2 DOUT1 DOUT0 tCSH tCSW Figure 8. Minimum SPI Programming Operation (Typically for Single Device Applications) 22 _____________________________________________________________________________________ Industrial Analog Current/ Voltage-Output Conditioners MAX15500/MAX15501 ACTIVE FRAME DIN X DIN13 DIN12 DIN11 DIN10 tDS SCLK tCSH DOUT Z tDOE CS_ tCR READY tCSR 1 tCSS 2 3 4 5 DIN9 DIN8 tCH 6 7 tCH 8 tCL DIN7 DIN6 tCP 9 tDOH 10 11 12 tDOT 13 tDOZ HIGH-Z tCSV 14 15 16 17 X DIN5 DIN4 DIN3 DIN2 DIN1 DIN0 X X X DOUT9 DOUT8 DOUT7 DOUT6 DOUT5 DOUT4 DOUT3 DOUT2 DOUT1 DOUT0 Figure 9. Extended SPI Programming Operation (Daisy-Chained Applications) ERROR REGISTER UPDATED, ERROR RE-EVALUATED SCLK tCSH DOUT Z tDOE CS_ 1 tCSS 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 X HIGH-Z DOUT9 tCSDOZ OPERATION ABORTED Figure 10. Aborted SPI Programming Operation (Invalid, Showing tCSDOZ and Internal Activity) Readback Operations Write to the command addresses 4h or 5h to read back the configuration register data or the internal error information through DOUT[9:0]. For error readback operations, each bit corresponds to a specific error condition, with multiple bits indicating multiple error conditions present. Intermittent Errors An intermittent error is defined as an error that is detected and is resolved before the error register is read back. When the error is resolved without intervention, the intermittent bit (bit 9) is set. The output short-circuit and output open-load errors trigger the intermittent bit. Internal over- temperature and supply voltage brownout do not trigger the intermittent bit. Error Reporting Applications The ERROR output is typically connected to an interrupt input of the system microcontroller. The MAX15500/ MAX15501 only issue an interrupt when a new error condition is detected. The devices do not issue interrupts when errors (either individual or multiple) are resolved or when already reported errors persist. The system microcontroller resets ERROR when the system microcontroller reads back the error register. ERROR does not assert again unless a different error occurs. ______________________________________________________________________________________ 23 Industrial Analog Current/ Voltage-Output Conditioners MAX15500/MAX15501 Table 5. SPI Commands COMMAND ADDRESS DIN[13:11] 000 001 010 011 100 101 110 111 No-op Write configuration Reserved Reserved Read error Read configuration Reserved Reserved NAME No operation. Write device configuration register. See Table 6 for details. Reserved, no operation. Reserved, no operation. Read error register status. See Table 7 for details. Read device configuration register. See Table 6 for details. Reserved, no operation. Reserved, no operation. DESCRIPTION Table 6. Configuration Register LOCATION FUNCTION DESCRIPTION Sets device operating mode. 000 Mode[0]: Standby 001 Mode[1]: Bipolar current: Q20mA 010 Mode[2]: Unipolar current: 0 to 20mA 011 Mode[3]: Unipolar current: 4mA to 20mA 100 Mode[4]: Standby 101 Mode[5]: Bipolar voltage: Q10V 110 Mode[6]: Unipolar voltage: 0 to 10V 111 Mode[7]: Unipolar voltage: 0 to 5V DIN[9:7] Mode[2:0] DIN[6:4] VBOTH[2:0] Sets supply voltage brownout threshold for error reporting. 000: Q10V 100: Q18V 001: Q12V 101: Q20V 010: Q14V 110: Q22V 011: Q16V 111: Q24V 0 = thermal protection off. 1 = thermal protection on. Reserved DIN[3] DIN[10], DIN[2:0] Thermal shutdown — Note: Modes 2h and 3h are functionally identical. Table 7. Readback Operations and Formatting DOUT BITS DOUT[9:0] DOUT[9] DOUT[8] DOUT[7] DOUT[6] DOUT[5] DOUT[4:0] See configuration register details in Table 6. Output intermittent fault. For details, see the Error Handling section. Output short circuit. This bit asserts when IOUT > 30mA in voltage and current modes for longer than 260ms. Output open load. This bit asserts when VOUT is within 30mV of AVDDO or AVSSO and there is no short-circuit condition for longer than 260ms. Internal overtemperature. This bit asserts when the die temperature exceeds +150NC. Supply brownout. This bit asserts when either supply has entered the brownout limits. See Table 6 for details. Reserved DESCRIPTION COMMAND ADDRESS DIN[13:11] = 101. READBACK DEVICE CONFIGURATION REGISTER COMMAND ADDRESS DIN[13:11] = 100. READBACK ERROR REGISTER 24 _____________________________________________________________________________________ Industrial Analog Current/ Voltage-Output Conditioners Since the MAX15500/MAX15501 do not use a continuous clock signal, the SPI read cycles are used to cycle the error detection and reporting logic. Continue to poll the device until the error readback reports an all clear status when resolving single or multiple errors. See below for examples of typical error handling situations and the effects of the SPI read operations. 1) Error resolved by the system. a) The MAX15500/MAX15501 detect an error condition and ERROR asserts. b) The host controller reads the error register for the first time. This has the effect of resetting ERROR. The data indicates to the host processor which error is active. c) The host processor resolves the error successfully. d) The host processor reads the error register for the second time. The data still shows that the error is present as the error persisted for some time after step b and before step c. If the error is either an open load or short circuit, the intermittent bit is set. An overtemperature or a brownout does not set the intermittent bit. Reading the register a second time resets the register. e) The host reads the error register for a third time. The data now shows the error is resolved and future occurrences of this error will trigger ERROR assertion. 2) Error resolved before the host processor reads error register. a) The MAX15500/MAX15501 detect an error condition and ERROR asserts, but the error resolves itself. b) The host controller reads the error register for the first time resetting ERROR. The data indicates to the host processor which error is active. The data also indicates to the host that the error has been resolved since the intermittent bit is set. c) The host processor reads the error register for the second time. The data still shows that the error is active. If the error is for an output fault, the data also indicates to the host that the error has been resolved since the intermittent bit is set. Reading the register a second time resets the register. 3) An error that cannot be resolved. a) The MAX15500/MAX15501 detect an error condition and ERROR asserts. b) The host controller reads the error register for the first time and resets ERROR. The data indicates to the host processor which error is active. c) The host processor takes action to resolve the error unsuccessfully. d) The host processor reads the error register for the second time. The data still shows that the error is present. e) The host processor reads the error for the third time. The data show the error to be unresolved. ERROR does not respond to the same error until the error is resolved and reported. ERROR asserts if different errors occur. MAX15500/MAX15501 Applications Information In current mode, there is approximately 1.0V across the current-sensing resistors at full scale. The current sensing resistor sets the gain and is calculated as follows: RSENSE = VSENSE_FS/IMAX where VSENSE_FS is the full-scale voltage across the sense resistor. See Table 8 for values of VSENSE_FS. The output gain in voltage mode is fixed as shown in Table 9. Setting the Output Gain in Current Mode Output Gain in Voltage Mode Use Table 10 to select the compensation capacitor. Selection of the Compensation Capacitor (CCOMP) Layout Considerations In the current-mode application, use Kelvin and a short connection from SENSERN and SENSERP to the RSENSE terminals to minimize gain-error drift. Balance and minimize all analog input traces for optimum performance. ______________________________________________________________________________________ 25 Industrial Analog Current/ Voltage-Output Conditioners MAX15500/MAX15501 Table 8. Recommended Current Setting Components VREFIN (V) OVERRANGE (%) BIPOLAR/ UNIPOLAR Unipolar +20 Bipolar 4.096 Unipolar +5 Bipolar Unipolar +20 Bipolar 2.500 Unipolar +5 Bipolar 1 Q1 47.5 Q21.05 0.8/47.5 2 1.009375 47.5 21.25 0.425/47.5 1 Q1 41.2 Q24.27 0.8/41.2 1 2 Q1.024 1.009375 48.7 41.2 Q21.03 24.5 0.5/48.7 0.425/41.2 2 1.02144 48.7 20.97 0.2625/48.7 1 Q1.024 42.2 Q24.27 0.5/42.2 MODE 2 VSENSE_FS (V) 1.02144 RSENSE (I) IOUT (mA) 24.205 IDEAL GAIN 0.2625/42.2 IDEAL TRANSFER FUNCTION IOUT = 0.2625 x (VAIN 0.05 x VREFIN)/42.2 IOUT = 0.5 x (VAIN - 0.5 x VREFIN)/42.2 IOUT = 0.2625 x (VAIN 0.05 x VREFIN)/48.7 IOUT = 0.5 x (VAIN - 0.5 x VREFIN)/48.7 IOUT = 0.425 x (VAIN 0.05 x VREFIN)/41.2 IOUT = 0.8 x (VAIN - 0.5 x VREFIN)/41.2 IOUT = 0.425 x (VAIN 0.05 x VREFIN)/47.5 IOUT = 0.8 x (VAIN - 0.5 x VREFIN)/47.5 42.2 Table 9. Full-Scale Output Voltages VREFIN (V) OVERRANGE (%) +20 4.096 +5 BIPOLAR/ UNIPOLAR Unipolar Bipolar Unipolar Bipolar +20 2.500 +5 Unipolar Bipolar Unipolar Bipolar MODE 7 6 5 7 6 5 7 6 5 7 6 5 IDEAL GAIN 1.5625 3.125 6.0 1.375 2.75 5.25 2.5125 5.0625 9.6 2.175 4.425 8.4 IDEAL TRANSFER FUNCTION VOUT = 1.5625 x (VAIN - 0.05 x VREFIN) VOUT = 3.125 x (VAIN - 0.05 x VREFIN) VOUT = 6.0 x (VAIN - 0.5 x VREFIN) VOUT = 1.375 x (VAIN - 0.05 x VREFIN) VOUT = 2.75 x (VAIN - 0.05 x VREFIN) VOUT = 5.25 x (VAIN - 0.5 x VREFIN) VOUT = 2.5125 x (VAIN - 0.05 x VREFIN) VOUT = 5.0625 x (VAIN - 0.05 x VREFIN) VOUT = 9.6 x (VAIN - 0.5 x VREFIN) VOUT = 2.175 x (VAIN - 0.05 x VREFIN) VOUT = 4.425 x (VAIN - 0.05 x VREFIN) VOUT = 8.4 x (VAIN - 0.5 x VREFIN) IDEAL VOUT (V) 6.08 12.16 Q12.288 5.3504 10.7008 Q10.752 5.96719 12.0234 Q12 5.16563 10.5094 Q10.5 26 _____________________________________________________________________________________ Industrial Analog Current/ Voltage-Output Conditioners Table 10. Recommended Compensation Capacitor for Various Load Conditions MODE Voltage Voltage Voltage Voltage Current Current Current Current Current Current Current Current Current Current Current Current CL (F) 0 to 1n 1n to 100n 100n to 1F 1F to 100F 0 to 1n 0 to 1n 0 to 1n 1n to 100n 1n to 100n 1n to 100n 100n to 1F 100n to 1F 100n to 1F 1F to 100F 1F to 100F 1F to 100F RL (kI) 1 1 1 1 20 to 750 20 to 750 20 to 750 20 to 750 20 to 750 20 to 750 20 to 750 20 to 750 20 to 750 20 to 750 20 to 750 20 to 750 LL (H) 0 0 0 0 0 to 20F 20F to 1m 1m to 50m 0 to 20F 20F to 1m 1m to 50m 0 to 20F 20F to 1m 1m to 50m 0 to 20F 20F to 1m 1m to 50m CCOMP (F) 0 1n 2.2n 4.7n 0 2.2n 100n 1n 2.2n 100n 2.2n 2.2n 100n 2.2n 2.2n 100n MAX15500/MAX15501 CL = Load capacitance. RL = Load resistance. LL = Load inductance. CCOMP = Compensation capacitance. Chip Information PROCESS: BiCMOS Package Information For the latest package outline information and land patterns (footprints), go to www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. PACKAGE TYPE 32 TQFN-EP PACKAGE CODE T3255+4 OUTLINE NO. 21-0140 LAND PATTERN NO. 90-0012 ______________________________________________________________________________________ 27 Industrial Analog Current/ Voltage-Output Conditioners MAX15500/MAX15501 Revision History REVISION NUMBER 0 1 REVISION DATE 7/09 2/11 Initial release Corrected description of DOUT pin in Pin Description section DESCRIPTION PAGES CHANGED — 13 Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 28 © Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 2011 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc.