VRE202 Precision Surface Mount Reference Supplies THALER CORPORATION • 2015 N. FORBES BOULEVARD • TUCSON, AZ. 85745 • (520) 882-4000 FEATURES APPLICATIONS • VERY HIGH ACCURACY: 2.5000 V OUTPUT ±200 µV • PRECISION A/D and D/A CONVERTERS • EXTREMELY LOW DRIFT: 0.6 ppm/°C 55°C to +125°C • TRANSDUCER EXCITATION • LOW WARM-UP DRIFT: 1 ppm Typ. • ACCURATE COMPARATOR THRESHOLD REFERENCE • EXCELLENT STABILITY: 6 ppm/1000 Hrs. Typ. • HIGH RESOLUTION SERVO SYSTEMS • EXCELLENT LINE REGULATION: 6ppm/V Typ. • DIGITAL VOLTMETERS • HERMETIC 20 TERMINAL CERAMIC LCC • MILITARY PROCESSING OPTION • HIGH PRECISION TEST and MEASUREMENT INSTRUMENTS DESCRIPTION VRE202 Series Precision Voltage References provide ultrastable +2.5000V outputs with ±200 µV initial accuracy and temperature coefficient as low as 0.6 ppm/°C over the full military temperature range. This improvement in accuracy is made possible by a unique, proprietary multipoint laser compensation technique developed by Thaler Corporation. Significant improvements have been made in other performance parameters as well, including initial accuracy, warm-up drift, line regulation, and longterm stability, making the VRE202 series the most accurate and stable 2.5V surface mount references available. SELECTION GUIDE Type Output Temperature Operating Range Max. Volt Deviation VRE202C VRE202CA +2.5V +2.5V -25°C to +85°C -25°C to +85°C 200µV 100µV VRE202M VRE202MA +2.5V +2.5V -55°C to +125°C -55°C to +125°C 400µV 200µV VRE202 devices are available in two operating temperature ranges, -25°C to +85°C and -55°C to +125°C, and two electrical performance grades. All devices are packaged in 20 terminal ceramic LCC packages for maximum long-term stability. "M" versions are screened for high reliability and quality. VRE202DS REV. D NOV 2000 ELECTRICAL SPECIFICATIONS VRE202 Vps =±15V, T = 25°C, RL = 10k? unless otherwise noted. MODEL C PARAMETERS MIN CA TYP MAX MIN M TYP MAX MA MIN TYP MAX MIN * -55 * * 125 * TYP MAX UNITS * 125 * V °C °C ABSOLUTE MAXIMUM RATINGS Power Supply +13.5 +22 Operating Temperature -25 85 Storage Temperature -65 150 Short Circuit Protection Continuous * * * * * * * -55 * * * * * * * OUTPUT VOLTAGE VRE202 +2.5 V OUTPUT VOLTAGE ERRORS Initial Error Warmup Drift Tmin - Tmax (1) Long-Term Stability Noise (.1-10Hz) 300 200 2 300 1 200 100 6 1.5 200 2 1 400 * * 200 * * * * µV ppm µV ppm/1000hrs µVpp OUTPUT CURRENT Range ±10 * * * mA REGULATION Line Load 6 3 10 * * * * * * * * * ppm/V ppm/mA OUTPUT ADJUSTMENT Range Temperature Coeff. POWER SUPPLY CURRENTS 10 4 * * * * mV µV/°C/mV (2) VRE202 +PS VRE202 -PS NOTES: * * 5 5 7 7 * * * * * * * * * * * * mA mA *Same as C Models. 1.Using the box method, the specified value is the maximum deviation from the output voltage at 25°C over the specified operating temperature range. 2.The specified values are unloaded. VRE202DS REV. D NOV 2000 TYPICAL PERFORMANCE CURVES VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE Temperature oC VRE202C Temperature oC VRE202CA VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE Temperature oC VRE202M Temperature oC VRE202MA QUIESCENT CURRENT VS. TEMP Temperature oC JUNCTION TEMP. RISE VS. OUTPUT CURRENT Output Current (mA) PSRR VS. FREQUENCY Frequency (Hz) VRE202DS REV. D NOV 2000 DISCUSSION OF PERFORMANCE THEORY OF OPERATION APPLICATION INFORMATION The following discussion refers to the schematic below. A FET current source is used to bias a 6.3 zener diode. The zener voltage is divided by the resistor network R1 and R2. This voltage is then applied to the noninverting input of the operational amplifier which amplifies the voltage to produce a 2.5000V output. The gain is determined by the resistor networks R3 and R4: G=1 + R4/R3. The 6.3 zener diode is used because it is the most stable diode over time and temperature. Figure 2 shows the proper connection of the VRE202 series voltage references with the optional trim resistors. Pay careful attention to the circuit layout to avoid noise pickup and voltage drops in the lines. The current source provides a closely regulated zener current, which determines the slope of the references’ voltage vs. temperature function. By trimming the zener current a lower drift over temperature can be achieved. But since the voltage vs. temperature function is nonlinear this compensation technique is not well suited for wide temperature ranges. Thaler Corporation has developed a nonlinear compensation network of thermistors and resistors that is used in the VRE series voltage references. This proprietary network eliminates most of the nonlinearity in the voltage vs. temperature function. By then adjusting the slope, Thaler Corporation produces a very stable voltage over wide temperature ranges. This network is less than 2% of the overall network resistance so it has a negligible effect on long term stability. By using highly stable resistors in our network, we produce a voltage reference that also has very good long term stability. The VRE202 series voltage references have the ground terminal brought out on two pins (pin 9 and pin 10) which are connected together internally. This allows the user to achieve greater accuracy when using a socket. Voltage references have a voltage drop across their power supply ground pin due to quiescent current flowing through the contact resistance. If the contact resistance was constant with time and temperature, this voltage drop could be trimmed out. When the reference is plugged into a socket, this source of error can be as high as 20ppm. By connecting pin 10 to the power supply ground and pin 9 to a high impedance ground point in the measurement circuit, the error due to the contact resistance can be eliminated. If the unit is soldered into place, the contact resistance is sufficiently small that it does not effect performance. VRE202 FIGURE 1 VRE202DS REV. D NOV 2000 EXTERNAL CONNECTIONS -15V 2 3 1 20 4 +15V 19 18 5 17 6 16 7 15 8 9 10 12 13 11 VOUT = +2.5V 14 ? Ref. Gnd. 10k? FIGURE 2 PIN CONFIGURATION NC -VIN NC NC NC 3 NC 2 1 20 19 4 18 NC 17 NC 16 NC +VIN 5 TOP VIEW NC 6 VRE202 NC 7 15 VOUT NC 8 14 NC 9 10 11 12 13 REF GND NC TRIM NC GND MECHANICAL INCHES MILLIMETER DIM MIN MAX MIN MAX A 0.090 0.110 2.29 2.79 B 0.022 0.028 0.56 0.71 D 0.342 0.358 8.68 9.09 D1 0.048 0.052 1.22 1.32 E 0.342 0.358 8.68 9.09 E1 0.045 0.055 1.114 1.40 j 0.010 REF .254 REF h 0.040 REF 1.02 REF L 0.045 0.055 1.14 1.40 VRE202DS REV. D NOV 2000 VRE204 Precision Surface Mount Reference Supply THALER CORPORATION • 2015 N. FORBES BOULEVARD • TUCSON, AZ. 85745 • (520) 882-4000 FEATURES APPLICATIONS • VERY HIGH ACCURACY: 4.5000 V OUTPUT ±0.4 mV • PRECISION A/D and D/A CONVERTERS • EXTREMELY LOW DRIFT: 0.6 ppm/°C -55°C to +125°C • TRANSDUCER EXCITATION • EXCELLENT STABILITY: 6ppm/1000 Hrs. Typ. • ACCURATE COMPARATOR THRESHOLD REFERENCE • EXCELLENT LINE REGULATION: 6 ppm/V Typ. • WIDE SUPPLY RANGE: +13.5 V to +22.0 V • HERMETIC 20 TERMINAL CERAMIC LCC • MILITARY PROCESSING AVAILABLE • HIGH RESOLUTION SERVO SYSTEMS • DIGITAL VOLTMETERS • HIGH PRECISION TEST and MEASUREMENT INSTRUMENTS DESCRIPTION VRE204 Series Precision Voltage References provide ultrastable +4.500 V outputs with up to ±0.4 mV initial accuracy and temperature coefficient as low as 0.6 ppm/°C over the full military temperature range. These references are specifically designed to be used with the Crystal Semiconductor line of successive-approximation type Analog-to-Digital Converters (ADCs). This line of ADCs sets new standards for temperature drift, which can only be as good as the external reference used. The Thaler VRE204 combined with a Crystal ADC will provide the lowest drift data conversion obtainable. SELECTION GUIDE Type Output Temperature Max. Volt Operating Range Deviation VRE204C +4.5V VRE204CA +4.5V -25°C to +85°C -25°C to +85°C 0.4mV 0.2mV VRE204M +4.5V VRE204MA +4.5V -55°C to +125°C -55°C to +125°C 0.6mV 0.3mV VRE204 series devices are available in two operating temperature ranges, -25°C to +85°C and -55°C to +125°C, and two performance grades. All devices are packaged in 20 terminal LCC ceramic packages for maximum long-term stability. "M" versions are screened for high reliability and quality. Superior stability, accuracy, and quality make the VRE204 ideal for all precision applications which may require a 4.5V reference. High-accuracy test and measurement instrumentation, and transducer excitation are some other applications which can benefit from the high accuracy of the VRE204. VRE204DS REV. C JUNE 1995 ELECTRICAL SPECIFICATIONS VRE204 Vps =±15V, T = 25°C, RL = 10KΩ unless otherwise noted. MODEL C PARAMETERS MIN CA TYP MAX MIN M TYP MAX MA MIN TYP MAX MIN * -55 * * 125 * TYP MAX UNITS ABSOLUTE MAXIMUM RATINGS Power Supply +13.5 +22 Operating Temperature -25 85 Storage Temperature -65 150 Short Circuit Protection Continuous * * * * * * * -55 * * 125 * * * * * * * V °C °C OUTPUT VOLTAGE VRE204 +4.5 V OUTPUT VOLTAGE ERRORS Initial Error Warmup Drift Tmin - Tmax (1) Long-Term Stability Noise (.1-10Hz) 800 400 2 800 1 400 200 6 3 400 2 * 600 * * 300 * * * * µV ppm µV ppm/1000hrs µVpp OUTPUT CURRENT Range ±10 * * * mA REGULATION Line Load 6 3 10 * * * * * * * * * ppm/V ppm/mA OUTPUT ADJUSTMENT Range Temperature Coeff. POWER SUPPLY CURRENTS 10 4 * * * * mV µV/°C/mV (2) VRE204 +PS NOTES: * * 5 7 * * * * * * mA *Same as C Models. 1.Using the box method, the specified value is the maximum deviation from the output voltage at 25°C over the specified operating temperature range. 2.The specified values are unloaded. VRE204DS REV. C JUNE 1995 TYPICAL PERFORMANCE CURVES VOUT vs. TEMPERATURE Temperature VRE204C VOUT vs. TEMPERATURE Temperature oC VRE204CA oC VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE Temperature oC VRE204M QUIESCENT CURRENT VS. TEMP Temperature oC Temperature oC VRE204MA JUNCTION TEMP. RISE VS. OUTPUT CURRENT Output Current (mA) PSRR VS. FREQUENCY Frequency (Hz) VRE204DS REV. C JUNE 1995 DISCUSSION OF PERFORMANCE THEORY OF OPERATION APPLICATION INFORMATION The following discussion refers to the schematic below. A FET current source is used to bias a 6.3 zener diode. The zener voltage is divided by the resistor network R1 and R2. This voltage is then applied to the noninverting input of the operational amplifier which amplifies the voltage to produce a 4.5000V output. The gain is determined by the resistor networks R3 and R4: G=1 + R4/R3. The 6.3 zener diode is used because it is the most stable diode over time and temperature. Figure 2 shows the proper connection of the VRE204 series voltage references with the optional trim resistors. Pay careful attention to the circuit layout to avoid noise pickup and voltage drops in the lines. The current source provides a closely regulated zener current, which determines the slope of the references’ voltage vs. temperature function. By trimming the zener current a lower drift over temperature can be achieved. But since the voltage vs. temperature function is nonlinear this compensation technique is not well suited for wide temperature ranges. Thaler Corporation has developed a nonlinear compensation network of thermistors and resistors that is used in the VRE series voltage references. This proprietary network eliminates most of the nonlinearity in the voltage vs. temperature function. By then adjusting the slope, Thaler Corporation produces a very stable voltage over wide temperature ranges. This network is less than 2% of the overall network resistance so it has a negligible effect on long term stability. By using highly stable resistors in our network, we produce a voltage reference that also has very good long term stability. The VRE204 series voltage references have the ground terminal brought out on two pins (pin 9 and pin 10) which are connected together internally. This allows the user to achieve greater accuracy when using a socket. Voltage references have a voltage drop across their power supply ground pin due to quiescent current flowing through the contact resistance. If the contact resistance was constant with time and temperature, this voltage drop could be trimmed out. When the reference is plugged into a socket, this source of error can be as high as 20ppm. By connecting pin 10 to the power supply ground and pin 9 to a high impedance ground point in the measurement circuit, the error due to the contact resistance can be eliminated. If the unit is soldered into place, the contact resistance is sufficiently small that it does not effect performance. VRE204 FIGURE 1 VRE204DS REV. C JUNE 1995 EXTERNAL CONNECTIONS 2 3 +15V 1 20 19 4 18 5 17 6 16 7 15 8 9 10 11 Ref. Gnd. 12 13 VOUT = +4.5V 14 ↓ 10k Ω FIGURE 2 PIN CONFIGURATION NC NC NC NC NC 3 2 1 20 19 18 NC TOP VIEW 17 NC VRE204 16 NC 7 15 VOUT 8 14 NC NC 4 VIN 5 NC 6 NC NC 9 REF GND 10 11 12 13 GND NC TRIM NC MECHANICAL INCHES MILLIMETER DIM MIN MAX MIN MAX A 0.090 0.110 2.29 2.79 B 0.022 0.028 0.56 0.71 D 0.342 0.358 8.68 9.09 D1 0.048 0.052 1.22 1.32 E 0.342 0.358 8.68 9.09 E1 0.045 0.055 1.114 1.40 j 0.010 REF .254 REF h 0.040 REF 1.02 REF L 0.045 0.055 1.14 1.40 VRE204DS REV. C JUNE 1995 VRE205 Precision Surface Mount Reference Supply THALER CORPORATION • 2015 N. FORBES BOULEVARD • TUCSON, AZ. 85745 • (520) 882-4000 FEATURES APPLICATIONS • PIN AND FUNCTION COMPATIBLE TO REF02 • PRECISION A/D and D/A CONVERTERS • VERY HIGH ACCURACY: 5.000 V OUTPUT ±0.4 mV • TRANSDUCER EXCITATION • EXTREMELY LOW DRIFT: 0.6 ppm/°C -55°C to +125°C • ACCURATE COMPARATOR THRESHOLD REFERENCE • EXCELLENT STABILITY: 6 ppm/1000 Hrs. Typ. • EXCELLENT LINE REGULATION: 6 ppm/V Typ. • WIDE SUPPLY RANGE: +13.5 V to -22.0 V • HERMETIC 20 TERMINAL CERAMIC LCC • HIGH RESOLUTION SERVO SYSTEMS • DIGITAL VOLTMETERS • HIGH PRECISION TEST and MEASUREMENT INSTRUMENTS • MILITARY PROCESSING OPTION DESCRIPTION VRE205 Series Precision Voltage References provides ultrastable +5.000 V outputs with ±0.4 mV initial accuracy and temperature coefficient as low as 0.6 ppm/°C over the full military temperature range. This improvement in accuracy is made possible by a unique, proprietary multipoint laser compensation technique developed by Thaler Corporation. Significant improvements have been made in other performance parameters as well, including initial accuracy, warm-up drift, line regulation, and longterm stability, making the VRE205 series the most accurate and stable 5V references available. SELECTION GUIDE Type Output Temperature Operating Range Max. Volt Deviation VRE205C VRE205CA VRE205M VRE205MA +5V +5V +5V +5V -25°C to +85°C -25°C to +85°C -55°C to +125°C -55°C to +125°C 0.4mV 0.2mV 0.6mV 0.3mV VRE205 series devices are available in two operating temperature ranges, -25°C to +85°C and -55°C to +125°C, and two performance grades. All devices are packaged in 20 terminal ceramic LCC packages for maximum long-term stability. "M" versions are screened for high reliability and quality. . VRE205DS REV. C JUNE 1995 ELECTRICAL SPECIFICATIONS VRE205 Vps =±15V, T = 25°C, RL = 10KΩ unless otherwise noted. MODEL C PARAMETERS MIN CA TYP MAX MIN M TYP MAX MA MIN TYP MAX MIN * -55 * * 125 * TYP MAX UNITS ABSOLUTE MAXIMUM RATINGS Power Supply +13.5 +22 Operating Temperature -25 85 Storage Temperature -65 150 Short Circuit Protection Continuous * * * * * * * -55 * * 125 * * * * * * * V °C °C OUTPUT VOLTAGE VRE205 +5 V OUTPUT VOLTAGE ERRORS Initial Error Warmup Drift Tmin - Tmax (1) Long-Term Stability Noise (.1-10Hz) 800 400 2 800 1 400 200 6 3 400 2 1 600 * * 300 * * * * µV ppm µV ppm/1000hrs µVpp OUTPUT CURRENT Range ±10 * * * mA REGULATION Line Load 6 3 10 * * * * * * * * * ppm/V ppm/mA OUTPUT ADJUSTMENT Range Temperature Coeff. POWER SUPPLY CURRENTS 10 4 * * * * mV µV/°C/mV (2) VRE205 +PS NOTES: * * 5 7 * * * * * * mA *Same as C Models. 1.Using the box method, the specified value is the maximum deviation from the output voltage at 25°C over the specified operating temperature range. 2.The specified values are unloaded. VRE205DS REV. C JUNE 1995 TYPICAL PERFORMANCE CURVES VOUT vs. TEMPERATURE Temperature VRE205C VOUT vs. TEMPERATURE Temperature oC VRE205CA oC VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE Temperature oC VRE205M QUIESCENT CURRENT VS. TEMP Temperature oC Temperature oC VRE205MA JUNCTION TEMP. RISE VS. OUTPUT CURRENT Output Current (mA) PSRR VS. FREQUENCY Frequency (Hz) VRE205DS REV. C JUNE 1995 DISCUSSION OF PERFORMANCE THEORY OF OPERATION APPLICATION INFORMATION The following discussion refers to the schematic below. A FET current source is used to bias a 6.3 zener diode. The zener voltage is divided by the resistor network R1 and R2. This voltage is then applied to the noninverting input of the operational amplifier which amplifies the voltage to produce a 5.000V output. The gain is determined by the resistor networks R3 and R4: G=1 + R4/R3. The 6.3 zener diode is used because it is the most stable diode over time and temperature. Figure 2 shows the proper connection of the VRE205 series voltage references with the optional trim resistors. Pay careful attention to the circuit layout to avoid noise pickup and voltage drops in the lines. The current source provides a closely regulated zener current, which determines the slope of the references’ voltage vs. temperature function. By trimming the zener current a lower drift over temperature can be achieved. But since the voltage vs. temperature function is nonlinear this compensation technique is not well suited for wide temperature ranges. Thaler Corporation has developed a nonlinear compensation network of thermistors and resistors that is used in the VRE series voltage references. This proprietary network eliminates most of the nonlinearity in the voltage vs. temperature function. By then adjusting the slope, Thaler Corporation produces a very stable voltage over wide temperature ranges. This network is less than 2% of the overall network resistance so it has a negligible effect on long term stability. By using highly stable resistors in our network, we produce a voltage reference that also has very good long term stability. The VRE205 series voltage references have the ground terminal brought out on two pins (pin 9 and pin 10) which are connected together internally. This allows the user to achieve greater accuracy when using a socket. Voltage references have a voltage drop across their power supply ground pin due to quiescent current flowing through the contact resistance. If the contact resistance was constant with time and temperature, this voltage drop could be trimmed out. When the reference is plugged into a socket, this source of error can be as high as 20ppm. By connecting pin 10 to the power supply ground and pin 9 to a high impedance ground point in the measurement circuit, the error due to the contact resistance can be eliminated. If the unit is soldered into place, the contact resistance is sufficiently small that it does not effect performance. VRE205 FIGURE 1 VRE205DS REV. C JUNE 1995 EXTERNAL CONNECTIONS 3 +15V 2 1 20 19 4 18 5 17 6 16 7 15 8 9 10 11 Ref. Gnd. 12 13 VOUT = +5.0V 14 ↓ 10k Ω FIGURE 2 PIN CONFIGURATION NC NC NC NC NC 3 2 1 20 19 18 NC TOP VIEW 17 NC VRE205 16 NC 7 15 VOUT 8 14 NC NC 4 VIN 5 NC 6 NC NC 9 REF GND 10 11 12 13 GND NC TRIM NC MECHANICAL INCHES MILLIMETER DIM MIN MAX MIN MAX A 0.090 0.110 2.29 2.79 B 0.022 0.028 0.56 0.71 D 0.342 0.358 8.68 9.09 D1 0.048 0.052 1.22 1.32 E 0.342 0.358 8.68 9.09 E1 0.045 0.055 1.114 1.40 j 0.010 REF .254 REF h 0.040 REF 1.02 REF L 0.045 0.055 1.14 1.40 VRE205DS REV. C JUNE 1995 VRE210 Precision Surface Mount Reference Supplies THALER CORPORATION • 2015 N. FORBES BOULEVARD • TUCSON, AZ. 85745 • (520) 882-4000 FEATURES APPLICATIONS • PIN AND FUNCTION COMPATIBLE WITH REF01 • PRECISION A/D and D/A CONVERTERS • VERY HIGH ACCURACY: 10.000 V OUTPUT ±0.3 mV • TRANSDUCER EXCITATION • EXTREMELY LOW DRIFT: 0.5 ppm/°C 55°C to +125°C • ACCURATE COMPARATOR THRESHOLD REFERENCE • LOW WARM-UP DRIFT: 1 ppm Typ. • HIGH RESOLUTION SERVO SYSTEMS • EXCELLENT STABILITY: 6 ppm/1000 Hrs. Typ. • DIGITAL VOLTMETERS • EXCELLENT LINE REGULATION: 3 ppm/V Typ. • HERMETIC 20 TERMINAL CERAMIC LCC • HIGH PRECISION TEST and MEASUREMENT INSTRUMENTS • MILITARY PROCESSING OPTION DESCRIPTION VRE210 Series Precision Voltage References provide ultrastable +10.000V outputs with ±0.3 mV initial accuracy and temperature coefficient as low as 0.5 ppm/°C over the full military temperature range. This improvement in accuracy is made possible by a unique, proprietary multipoint laser compensation technique developed by Thaler Corporation. Significant improvements have been made in other performance parameters as well, including initial accuracy, warm-up drift, line regulation, and long-term stability, making the VRE210 series the most accurate and stable 10V surface mount references available. SELECTION GUIDE Output Temperature Operating Range Max. Volt Deviation VRE210C VRE210CA +10V +10V -25°C to +85°C -25°C to +85°C 0.6mV 0.3mV VRE210M VRE210MA +10V +10V -55°C to +125°C -55°C to +125°C 1.0mV 0.5mV Type VRE210 devices are available in two operating temperature ranges, -25°C to +85°C and -55°C to +125°C, and two electrical performance grades. All devices are packaged in 20 terminal ceramic LCC packages for maximum long-term stability. "M" versions are screened for high reliability and quality. VRE210DS REV. C JUNE 1995 ELECTRICAL SPECIFICATIONS VRE210 Vps =±15V, T = 25°C, RL = 10KΩ unless otherwise noted. MODEL C PARAMETERS MIN CA TYP MAX MIN M TYP MAX MA MIN TYP MAX MIN * -55 * * 125 * TYP MAX UNITS ABSOLUTE MAXIMUM RATINGS Power Supply +13.5 +22 Operating Temperature -25 85 Storage Temperature -65 150 Short Circuit Protection Continuous * * * * * * * -55 * * 125 * * * * * * * V °C °C OUTPUT VOLTAGE VRE210 +10 V OUTPUT VOLTAGE ERRORS Initial Error Warmup Drift Tmin - Tmax (1) Long-Term Stability Noise (.1-10Hz) 500 300 2 800 1 600 300 6 6 400 2 1 1000 * * 500 * * * * µV ppm µV ppm/1000hrs µVpp OUTPUT CURRENT Range ±10 * * * mA REGULATION Line Load 3 3 10 * * * * * * * * * ppm/V ppm/mA OUTPUT ADJUSTMENT Range Temperature Coeff. POWER SUPPLY CURRENTS 20 4 * * * * mV mV/°C/mV (2) VRE210 +PS NOTES: * * 5 7 * * * * * * mA *Same as C Models. 1.Using the box method, the specified value is the maximum deviation from the output voltage at 25°C over the specified operating temperature range. 2.The specified values are unloaded. VRE210DS REV. C JUNE 1995 TYPICAL PERFORMANCE CURVES VOUT vs. TEMPERATURE Temperature VRE210C VOUT vs. TEMPERATURE Temperature oC VRE210CA oC VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE Temperature oC VRE210M QUIESCENT CURRENT VS. TEMP Temperature oC Temperature oC VRE210MA JUNCTION TEMP. RISE VS. OUTPUT CURRENT Output Current (mA) PSRR VS. FREQUENCY Frequency (Hz) VRE210DS REV. C JUNE 1995 DISCUSSION OF PERFORMANCE THEORY OF OPERATION APPLICATION INFORMATION The following discussion refers to the schematic below. In operation, approximately 6.3 volts is applied to the noninverting input of the op amp. The voltage is amplified by the op amp to produce a 10.000V output. The gain is determined by the networks R1 and R2: G=1 + R2/R1. The 6.3V zener diode is used because it is the most stable diode over time and temperature. Figure 2 shows the proper connection of the VRE210 series voltage references with the optional trim resistors. Pay careful attention to the circuit layout to avoid noise pickup and voltage drops in the lines. The zener operating current is derived from the regulated output voltage through R3. This feedback arrangement provides a closely regulated zener current. This current determines the slope of the references' voltage vs. temperature function. By trimming the zener current a lower drift over temperature can be achieved. But since the voltage vs. temperature function is nonlinear this compensation technique is not well suited for wide temperature ranges. Thaler Corporation has developed a nonlinear compensation network of thermistors and resistors that is used in the VRE series voltage references. This proprietary network eliminates most of the nonlinearity in the voltage vs. temperature function. By then adjusting the slope, Thaler Corporation produces a very stable voltage over wide temperature ranges. This network is less than 2% of the overall network resistance so it has a negligible effect on long term stability. By using highly stable resistors in our network, we produce a voltage reference that also has very good long term stability. The VRE210 series voltage references have the ground terminal brought out on two pins (pin 9 and pin 10) which are connected together internally. This allows the user to achieve greater accuracy when using a socket. Voltage references have a voltage drop across their power supply ground pin due to quiescent current flowing through the contact resistance. If the contact resistance was constant with time and temperature, this voltage drop could be trimmed out. When the reference is plugged into a socket, this source of error can be as high as 20ppm. By connecting pin 10 to the power supply ground and pin 9 to a high impedance ground point in the measurement circuit, the error due to the contact resistance can be eliminated. If the unit is soldered into place, the contact resistance is sufficiently small that it does not effect performance. VRE210 FIGURE 1 VRE210DS REV. C JUNE 1995 EXTERNAL CONNECTIONS 3 +15V 2 1 20 4 19 18 5 17 6 16 7 15 8 14 9 10 12 13 11 VOUT = +10V ↓ Ref. Gnd. 10kΩ FIGURE 2 PIN CONFIGURATION NC NC NC NC NC 3 2 1 20 19 18 NC TOP VIEW 17 NC VRE210 16 NC 7 15 VOUT 8 14 NC NC 4 VIN 5 NC 6 NC NC 9 10 11 REF GND GND 12 13 NC TRIM NC MECHANICAL INCHES MILLIMETER DIM MIN MAX MIN MAX A 0.090 0.110 2.29 2.79 B 0.022 0.028 0.56 0.71 D 0.342 0.358 8.68 9.09 D1 0.048 0.052 1.22 1.32 E 0.342 0.358 8.68 9.09 E1 0.045 0.055 1.114 1.40 j 0.010 REF .254 REF h 0.040 REF 1.02 REF L 0.045 0.055 1.14 1.40 VRE210DS REV. C JUNE 1995