VRE304-6A

VRE302 Low Cost Precision Reference THALER CORPORATION • 2015 N. FORBES BOULEVARD • TUCSON, AZ. 85745 • (520) 882-4000 FEATURES • 2.500 V OUTPUT ± 0.250 mV (.01%) • TEMPERATURE DRIFT: 0.6 ppm/°C • LOW NOISE: 1.5µV p-p (0.1-10Hz) • INDUSTRY STD PINOUT- 8 PIN DIP OR SURFACE MOUNT PACKAGE •EXCELLENT LINE REGULATION: 6ppm/V Typ. • OUTPUT TRIM CAPABILITY FIGURE 1 N.C. +VIN TEMP GND 1 2 3 4 8 NOISE REF. GND VOUT TRIM PIN CONFIGURATION VRE302 7 6 5 TOP VIEW DESCRIPTION The VRE302 is a low cost, high precision 2.5V reference. Packaged in the industry standard 8 pin DIP, the device is ideal for upgrading systems that use lower performance references. The device provides ultrastable +2.500V output with ±0.2500 mV (.01%) initial accuracy and a temperature coefficient of 0.6 ppm/°C. This improvement in accuracy is made possible by a unique, patented 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 VRE302 series the most accurate reference available in the standard 8 pin DIP package. For enhanced performance, the VRE302 has an external trim option for users who want less than 0.01% initial error. A reference ground pin is provided to eliminate socket contact resistance errors. The VRE302 is recommended for use as a reference for 14, 16, or 18 bit D/A converters which require an external precision reference. The device is also ideal for calibrating scale factor on high resolution A/D converters. The VRE302 offers superior performance over monolithic references. SELECTION GUIDE Initial Error mV 0.25 0.40 0.50 0.25 0.40 0.50 Model VRE302A VRE302B VRE302C VRE302J VRE302K VRE302L Temp. Coeff. ppm/°C 0.6 1.0 2.0 0.6 1.0 2.0 Temp. Range °C 0°C to +70°C 0°C to +70°C 0°C to +70°C -40°C to +85°C -40°C to +85°C -40°C to +85°C For package option add D for DIP or S for Surface Mount to end of model number. VRE302DS REV. F MAY 2001 ELECTRICAL SPECIFICATIONS MODEL PARAMETER ABSOLUTE RATINGS Power Supply Operating Temp. (A,B,C) Operating Temp. (J,K,L) Storage Temperature Short Circuit Protection OUTPUT VOLTAGE VRE302 (1) Temp. Sensor Voltage OUTPUT VOLTAGE ERRORS Initial Error Warmup Drift Tmin - Tmax (3) Long-Term Stability Noise (.1-10Hz) (4) OUTPUT CURRENT Range REGULATION Line Load OUTPUT ADJUSTMENT Range POWER SUPPLY CURRENTS VRE302 +PS (5) (2) Vps =+15V, T = 25°C, RL = 10KΩ unless otherwise noted. VRE302 B/K MAX MIN TYP MAX MIN A/J MIN TYP C/L TYP MAX UNITS +13.5 +15 +22 0 +70 -40 +85 -65 +150 Continuous * * * * * * * * * * * * * * * * * * V °C °C °C * * 2.500 630 * * * * V mV 0.25 1 0.6 6 1.5 * * 2 0.40 3 1.0 * * 0.50 2.0 mV ppm ppm/°C ppm/1000hrs µVpp ±10 * * mA 6 3 10 * * * * * * ppm/V ppm/mA 10 * * mV 5 7 * * * * mA NOTES: *Same as A/J Models. 1. The temp. reference TC is 2.1mV/ °C 2. The specified values are without external trim. 3. The temperature coefficient is determined by the box method using the following formula: Vmax - Vmin T.C. = Vnominal x (Tmax-Tmin) x 106 4. The specified values are without the external noise reduction capacitor. 5. The specified values are unloaded. VRE302DS REV. F MAY 2001 TYPICAL PERFORMANCE CURVES VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE Temperature oC VRE302A Temperature oC VRE302B Temperature oC VRE302C VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE Temperature oC VRE302J Temperature oC VRE302K Temperature oC VRE302L POSITIVE OUTPUT (TYP) QUIESCENT CURRENT VS. TEMP JUNCTION TEMP. RISE VS. OUTPUT CURRENT PSRR VS. FREQUENCY Temperature oC Output Current (mA) Frequency (Hz) VRE302DS REV. F MAY 2001 DISCUSSION OF PERFORMANCE THEORY OF OPERATION The following discussion refers to the schematic in figure 2 below. A FET current source is used to bias a 6.3V 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 2.500V output. The gain is determined by the resistor networks R3 and R4: G=1 + R4/R3. The 6.3V zener diode is used because it is the most stable diode over time and temperature. 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 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. Figure 3 shows the proper connection of the VRE302 series voltage references with the optional trim resistor for initial error. The VRE302 reference has the ground terminal brought out on two pins (pin 4 and pin 7) 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 4 to the power supply ground and pin 7 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. Pay careful attention to the circuit layout to avoid noise pickup and voltage drops in the lines. VRE302 FIGURE 2 EXTERNAL CONNECTIONS + VIN 2 8 V TEMP OUT 3 6 + VOUT 10kΩ OPTIONAL FINE TRIM ADJUSTMENT OPTIONAL NOISE REDUCTION CAPACITOR VRE302 CN 1µF 7 4 5 FIGURE 3 REF. GND VRE302DS REV. F MAY 2001 FIGURE 3 MECHANICAL D D1 D2 INCHES DIM A B B1 MIN .115 .098 .046 .107 .009 .052 .397 .372 MAX .125 .102 .051 .113 .012 .058 .403 .380 MILLIMETER MIN 2.92 2.48 1.14 2.71 0.22 1.32 10.0 9.44 MAX 3.17 2.59 1.29 2.89 0.30 1.47 10.2 9.65 DIM D2 E E1 E2 P Q S INCHES MIN .018 .507 .397 .264 .085 .020 .045 MAX .023 .513 .403 .270 .095 .030 .055 MILLIMETER MIN 0.46 12.8 10.0 6.70 2.15 .508 1.14 MAX 0.58 13.0 10.2 6.85 2.41 .762 1.39 E2 E1 E C C1 C2 D PIN 1 IDENTIFIER D1 A Q BASE SEATING E1 P C1 C2 C B B1 FIGURE 4 S INCHES DIM A B B1 B2 C D D1 MIN .115 .018 .046 .098 .009 .397 .372 MAX .125 .022 .051 .102 .012 .403 .380 MILLIMETER MIN 2.92 .457 1.14 2.48 0.22 10.0 9.44 MAX 3.17 .558 1.29 2.59 0.30 10.2 9.65 DIM E E1 G1 L P Q S INCHES MIN .397 .264 .290 .195 .085 .055 .045 MAX .403 .270 .310 .215 .095 .065 .055 MILLIMETER MIN 10.0 6.70 7.36 4.95 2.15 1.39 1.14 MAX 10.2 6.85 7.87 5.46 2.41 1.65 1.39 VRE302DS REV. F MAY 2001 VRE302-6 Low Cost Precision Reference THALER CORPORATION • 2015 N. FORBES BOULEVARD • TUCSON, AZ. 85745 • (520) 882-4000 FEATURES • 2.048 V OUTPUT ± 0.205 mV (.01%) • TEMPERATURE DRIFT: 0.6 ppm/°C • LOW NOISE: 1.5µV p-p (0.1-10Hz) • INDUSTRY STD PINOUT- 8 PIN DIP OR SURFACE MOUNT PACKAGE •EXCELLENT LINE REGULATION: 6ppm/V Typ. • OUTPUT TRIM CAPABILITY FIGURE 1 N.C. +VIN TEMP GND 1 2 3 4 8 NOISE REF. GND VOUT TRIM PIN CONFIGURATION VRE302-6 7 6 5 TOP VIEW DESCRIPTION The VRE302-6 is a low cost, high precision 2.5V reference. Packaged in the industry standard 8 pin DIP, the device is ideal for upgrading systems that use lower performance references. The device provides ultrastable +2.048V output with ±0.205 mV (.01%) initial accuracy and a temperature coefficient of 0.6 ppm/°C. This improvement in accuracy is made possible by a unique, patented 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 VRE302-6 series the most accurate reference available in the standard 8 pin DIP package. For enhanced performance, the VRE302-6 has an external trim option for users who want less than 0.01% initial error. A reference ground pin is provided to eliminate socket contact resistance errors. The VRE302-6 is recommended for use as a reference for 14, 16, or 18 bit D/A converters which require an external precision reference. The device is also ideal for calibrating scale factor on high resolution A/D converters. The VRE3026 offers superior performance over monolithic references. SELECTION GUIDE Initial Error mV 0.20 0.35 0.40 0.20 0.35 0.40 Model VRE302-6A VRE302-6B VRE302-6C VRE302-6J VRE302-6K VRE302-6L Temp. Coeff. ppm/°C 0.6 1.0 2.0 0.6 1.0 2.0 Temp. Range °C 0°C to +70°C 0°C to +70°C 0°C to +70°C -40°C to +85°C -40°C to +85°C -40°C to +85°C For package option add D for DIP or S for Surface Mount to end of model number. VRE302-6DS REV. B MAY 2001 ELECTRICAL SPECIFICATIONS MODEL PARAMETER ABSOLUTE RATINGS Power Supply Operating Temp. (A,B,C) Operating Temp. (J,K,L) Storage Temperature Short Circuit Protection OUTPUT VOLTAGE VRE302-6 (1) Temp. Sensor Voltage OUTPUT VOLTAGE ERRORS Initial Error Warmup Drift Tmin - Tmax (3) Long-Term Stability Noise (.1-10Hz) (4) OUTPUT CURRENT Range REGULATION Line Load OUTPUT ADJUSTMENT Range POWER SUPPLY CURRENTS VRE302-6 +PS (5) (2) Vps =+15V, T = 25°C, RL = 10KΩ unless otherwise noted. VRE302-6 B/K MAX MIN TYP MAX MIN A/J MIN TYP C/L TYP MAX UNITS +13.5 +15 +22 0 +70 -40 +85 -65 +150 Continuous * * * * * * * * * * * * * * * * * * V °C °C °C * * 2.048 630 * * * * V mV 0.20 1 0.6 6 1.5 * * 2 0.35 3 1.0 * * 0.40 2.0 mV ppm ppm/ °C ppm/1000hrs µVpp ±10 * * mA 6 3 10 * * * * * * ppm/V ppm/mA 10 * * mV 5 7 * * * * mA NOTES: *Same as A/J Models. 1. The temp. reference TC is 2.1mV/ °C 2. The specified values are without external trim. 3. The temperature coefficient is determined by the box method using the following formula: Vmax - Vmin T.C. = Vnominal x (Tmax-Tmin) x 106 4. The specified values are without the external noise reduction capacitor. 5. The specified values are unloaded. VRE302-6DS REV. B MAY 2001 TYPICAL PERFORMANCE CURVES VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE Temperature oC VRE302-6A Temperature oC VRE302-6B Temperature oC VRE302-6C VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE Temperature oC VRE302-6J Temperature oC VRE302-6K Temperature oC VRE302-6L QUIESCENT CURRENT VS. TEMP JUNCTION TEMP. RISE VS. OUTPUT CURRENT PSRR VS. FREQUENCY Temperature oC Output Current (mA) Frequency (Hz) VRE302-6DS REV. B MAY 2001 DISCUSSION OF PERFORMANCE THEORY OF OPERATION The following discussion refers to the schematic in figure 2 below. A FET current source is used to bias a 6.3V 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 2.048V output. The gain is determined by the resistor networks R3 and R4: G=1 + R4/R3. The 6.3V zener diode is used because it is the most stable diode over time and temperature. 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 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. Figure 3 shows the proper connection of the VRE302-6 series voltage references with the optional trim resistor for initial error. The VRE302-6 reference has the ground terminal brought out on two pins (pin 4 and pin 7) 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 4 to the power supply ground and pin 7 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. Pay careful attention to the circuit layout to avoid noise pickup and voltage drops in the lines. VRE302-6 FIGURE 2 EXTERNAL CONNECTIONS + VIN 2 8 V TEMP OUT 3 6 + VOUT 10kΩ OPTIONAL FINE TRIM ADJUSTMENT OPTIONAL NOISE REDUCTION CAPACITOR VRE302-6 CN 1µF 7 4 5 FIGURE 3 REF. GND VRE302-6DS REV. B MAY 2001 MECHANICAL FIGURE 3 D D1 D2 INCHES DIM A B B1 MIN .115 .098 .046 .107 .009 .052 .397 .372 MAX .125 .102 .051 .113 .012 .058 .403 .380 MILLIMETER MIN 2.92 2.48 1.14 2.71 0.22 1.32 10.0 9.44 MAX 3.17 2.59 1.29 2.89 0.30 1.47 10.2 9.65 DIM D2 E E1 E2 P Q S INCHES MIN .018 .507 .397 .264 .085 .020 .045 MAX .023 .513 .403 .270 .095 .030 .055 MILLIMETER MIN 0.46 12.8 10.0 6.70 2.15 .508 1.14 MAX 0.58 13.0 10.2 6.85 2.41 .762 1.39 E2 E1 E C C1 C2 D PIN 1 IDENTIFIER D1 A Q BASE SEATING E1 P C1 C2 C B B1 FIGURE 4 S INCHES DIM A B B1 B2 C D D1 MIN .115 .018 .046 .098 .009 .397 .372 MAX .125 .022 .051 .102 .012 .403 .380 MILLIMETER MIN 2.92 .457 1.14 2.48 0.22 10.0 9.44 MAX 3.17 .558 1.29 2.59 0.30 10.2 9.65 DIM E E1 G1 L P Q S INCHES MIN .397 .264 .290 .195 .085 .055 .045 MAX .403 .270 .310 .215 .095 .065 .055 MILLIMETER MIN 10.0 6.70 7.36 4.95 2.15 1.39 1.14 MAX 10.2 6.85 7.87 5.46 2.41 1.65 1.39 VRE302-6DS REV. B MAY 2001 VRE303 Low Cost Precision Reference THALER CORPORATION • 2015 N. FORBES BOULEVARD • TUCSON, AZ. 85745 • (520) 882-4000 FEATURES • 3.000 V OUTPUT ± 0.300 mV (.01%) PIN CONFIGURATION • TEMPERATURE DRIFT: 0.6 ppm/°C • LOW NOISE: 1.5µV p-p (0.1-10Hz) • INDUSTRY STD PINOUT- 8 PIN DIP OR SURFACE MOUNT PACKAGE •EXCELLENT LINE REGULATION: 6ppm/V Typ. • OUTPUT TRIM CAPABILITY FIGURE 1 N/C +VIN TEMP GND 1 2 3 4 8 NOISE REDUCTION REF. GND VOUT TRIM VRE303 TOP VIEW 7 6 5 DESCRIPTION The VRE303 is a low cost, high precision 3.0V reference. Packaged in the industry standard 8 pin DIP, the device is ideal for upgrading systems that use lower performance references. The device provides ultrastable +3.000V output with ±0.3000 mV (.01%) initial accuracy and a temperature coefficient of 0.6 ppm/°C. This improvement in accuracy is made possible by a unique, patented 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 VRE303 series the most accurate reference available in the standard 8 pin DIP package. For enhanced performance, the VRE303 has an external trim option for users who want less than 0.01% initial error. For ultra low noise applications, an external capacitor can be attached between the noise reduction pin and the ground pin. A reference ground pin is provided to eliminate socket contact resistance errors. The VRE303 is recommended for use as a reference for 14, 16, or 18 bit D/A converters which require an external precision reference. The device is also ideal for calibrating scale factor on high resolution A/D converters. The VRE303 offers superior performance over monolithic references. SELECTION GUIDE Initial Error mV 0.30 0.48 0.60 0.30 0.48 0.60 Model VRE303A VRE303B VRE303C VRE303J VRE303K VRE303L Temp. Coeff. ppm/°C 0.6 1.0 2.0 0.6 1.0 2.0 Temp. Range °C 0°C to +70°C 0°C to +70°C 0°C to +70°C -40°C to +85°C -40°C to +85°C -40°C to +85°C For package option add D for DIP or S for Surface Mount to end of model number. VRE303DS REV. B MAY 2001 ELECTRICAL SPECIFICATIONS Vps =+15V, T = 25°C, RL = 10KΩ unless otherwise noted. VRE303 B/K MAX MIN TYP MAX MIN MODEL PARAMETER ABSOLUTE RATINGS Power Supply Operating Temp. (A,B,C) Operating Temp. (J,K,L) Storage Temperature Short Circuit Protection OUTPUT VOLTAGE VRE303 (1) Temp. Sensor Voltage OUTPUT VOLTAGE ERRORS Initial Error Warmup Drift Tmin - Tmax (3) Long-Term Stability Noise (.1-10Hz) (4) OUTPUT CURRENT Range REGULATION Line Load OUTPUT ADJUSTMENT Range (5) (2) A/J MIN TYP C/L TYP MAX UNITS +14 0 -40 -65 +16 +70 +85 +150 Continuous +15 * * * * * * * * * * * * * * * * * * V °C °C °C * * 3.000 630 * * * * V mV 0.30 1 0.6 6 2.0 * * 2 0.48 3 1.0 * * 0.60 2.0 mV ppm ppm/°C ppm/1000hrs µVpp ±10 * * mA 6 3 10 * * * * * * ppm/V ppm/mA 10 * * mV POWER SUPPLY CURRENTS VRE303 +PS NOTES: *Same as A/J Models. 5 7 * * * * mA 1. The temp. reference TC is 2.1mV/ °C 2. The specified values are without external trim. 3. The temperature coefficient is determined by the box method using the following formula: Vmax - Vmin T.C. = Vnominal x (Tmax-Tmin) x 106 4. The specified values are without the external noise reduction capacitor. 5. The specified values are unloaded. VRE303DS REV. B MAY 2001 TYPICAL PERFORMANCE CURVES VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE Temperature oC VRE303A Temperature oC VRE303B Temperature oC VRE303C VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE Temperature oC VRE303J Temperature oC VRE303K Temperature oC VRE303L QUIESCENT CURRENT VS. TEMP JUNCTION TEMP. RISE VS. OUTPUT CURRENT PSRR VS. FREQUENCY Temperature oC Output Current (mA) Frequency (Hz) VRE303DS REV. B MAY 2001 DISCUSSION OF PERFORMANCE THEORY OF OPERATION The following discussion refers to the schematic in figure 2 below. A FET current source is used to bias a 6.3V 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 3.000V output. The gain is determined by the resistor networks R3 and R4: G=1 + R4/R3. The 6.3V zener diode is used because it is the most stable diode over time and temperature. 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 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. Figure 3 shows the proper connection of the VRE303 series voltage references with the optional trim resistor for initial error and the optional capacitor for noise reduction. The VRE303 reference has the ground terminal brought out on two pins (pin 4 and pin 7) 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 4 to the power supply ground and pin 7 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. Pay careful attention to the circuit layout to avoid noise pickup and voltage drops in the lines. VRE303 FIGURE 2 EXTERNAL CONNECTIONS + VIN 2 8 V TEMP OUT 3 6 + VOUT 10kΩ OPTIONAL FINE TRIM ADJUSTMENT OPTIONAL NOISE REDUCTION CAPACITOR VRE303 CN 1µF 7 4 5 FIGURE 3 REF. GND VRE303DS REV. B MAY 2001 FIGURE 3 MECHANICAL D D1 D2 INCHES DIM A B B1 MIN .115 .098 .046 .107 .009 .052 .397 .372 MAX .125 .102 .051 .113 .012 .058 .403 .380 MILLIMETER MIN 2.92 2.48 1.14 2.71 0.22 1.32 10.0 9.44 MAX 3.17 2.59 1.29 2.89 0.30 1.47 10.2 9.65 DIM D2 E E1 E2 P Q S INCHES MIN .018 .507 .397 .264 .085 .020 .045 MAX .023 .513 .403 .270 .095 .030 .055 MILLIMETER MIN 0.46 12.8 10.0 6.70 2.15 .508 1.14 MAX 0.58 13.0 10.2 6.85 2.41 .762 1.39 E2 E1 E C C1 C2 D PIN 1 IDENTIFIER D1 A Q BASE SEATING E1 P C1 C2 C B B1 FIGURE 4 S INCHES DIM A B B1 B2 C D D1 MIN .115 .018 .046 .098 .009 .397 .372 MAX .125 .022 .051 .102 .012 .403 .380 MILLIMETER MIN 2.92 .457 1.14 2.48 0.22 10.0 9.44 MAX 3.17 .558 1.29 2.59 0.30 10.2 9.65 DIM E E1 G1 L P Q S INCHES MIN .397 .264 .290 .195 .085 .055 .045 MILLIMETER MAX 10.2 6.85 7.87 5.46 2.41 1.65 1.39 MAX MIN .403 .270 .310 .215 .095 .065 .055 10.0 6.70 7.36 4.95 2.15 1.39 1.14 VRE303DS REV. B MAY 2001 VRE304 Low Cost Precision Reference THALER CORPORATION • 2015 N. FORBES BOULEVARD • TUCSON, AZ. 85745 • (520) 882-4000 FEATURES • 4.500 V OUTPUT ± 0.450 mV (.01%) • TEMPERATURE DRIFT: 0.6 ppm/°C • LOW NOISE: 3µV p-p (0.1-10Hz) • INDUSTRY STD PINOUT- 8 PIN DIP OR SURFACE MOUNT PACKAGE •EXCELLENT LINE REGULATION: 6ppm/V Typ. • OUTPUT TRIM CAPABILITY FIGURE 1 N/C +VIN TEMP GND 1 2 3 4 8 PIN CONFIGURATION NOISE REDUCTION REF. GND VOUT TRIM VRE304 TOP VIEW 7 6 5 DESCRIPTION The VRE304 is a low cost, high precision 4.5V reference. Packaged in the industry standard 8 pin DIP, the device is ideal for upgrading systems that use lower performance references. The device provides ultrastable +4.500V output with ±0.4500 mV (.01%) initial accuracy and a temperature coefficient of 0.6 ppm/°C. This improvement in accuracy is made possible by a unique, patented 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 VRE304 series the most accurate reference available in the standard 8 pin DIP package. For enhanced performance, the VRE304 has an external trim option for users who want less than 0.01% initial error. For ultra low noise applications, an external capacitor can be attached between the noise reduction pin and the ground pin. A reference ground pin is provided to eliminate socket contact resistance errors. The VRE304 is recommended for use as a reference for 14, 16, or 18 bit D/A converters which require an external precision reference. The device is also ideal for calibrating scale factor on high resolution A/D converters. The VRE304 offers superior performance over monolithic references. SELECTION GUIDE Initial Error mV 0.45 0.70 0.90 0.45 0.70 0.90 Model VRE304A VRE304B VRE304C VRE304J VRE304K VRE304L Temp. Coeff. ppm/°C 0.6 1.0 2.0 0.6 1.0 2.0 Temp. Range °C 0°C to +70°C 0°C to +70°C 0°C to +70°C -40°C to +85°C -40°C to +85°C -40°C to +85°C For package option add D for DIP or S for Surface Mount to end of model number. VRE304DS REV. D MAY 2001 ELECTRICAL SPECIFICATIONS Vps =+15V, T = 25°C, RL = 10KΩ unless otherwise noted. VRE304 B/K MAX MIN TYP MAX MIN MODEL PARAMETER ABSOLUTE RATINGS Power Supply Operating Temp. (A,B,C) Operating Temp. (J,K,L) Storage Temperature Short Circuit Protection OUTPUT VOLTAGE VRE304 (1) Temp. Sensor Voltage OUTPUT VOLTAGE ERRORS Initial Error Warmup Drift Tmin - Tmax (3) Long-Term Stability Noise (.1-10Hz) (4) OUTPUT CURRENT Range REGULATION Line Load OUTPUT ADJUSTMENT Range POWER SUPPLY CURRENTS VRE304 +PS NOTES: *Same as A/J Models. (5) (2) A/J MIN TYP C/L TYP MAX UNITS +13.5 0 -40 -65 +22 +70 +85 +150 Continuous +15 * * * * * * * * * * * * * * * * * * V °C °C °C * * 4.500 630 * * * * V mV 0.45 1 0.6 6 3 * * 2 0.70 3 1.0 * * 0.90 2.0 mV ppm ppm/°C ppm/1000hrs µVpp ±10 * * mA 6 3 10 * * * * * * ppm/V ppm/mA 10 * * mV 5 7 * * * * mA 1. The temp. reference TC is 2.1mV/ °C 2. The specified values are without external trim. 3. The temperature coefficient is determined by the box method using the following formula: Vmax - Vmin T.C. = Vnominal x (Tmax-Tmin) x 106 4. The specified values are without the external noise reduction capacitor. 5. The specified values are unloaded. VRE304DS REV. D MAY 2001 TYPICAL PERFORMANCE CURVES VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE Temperature oC VRE304A Temperature oC VRE304B Temperature oC VRE304C VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE Temperature oC VRE304J Temperature oC VRE304K Temperature oC VRE304L QUIESCENT CURRENT VS. TEMP JUNCTION TEMP. RISE VS. OUTPUT CURRENT PSRR VS. FREQUENCY Temperature oC Output Current (mA) Frequency (Hz) VRE304DS REV. D MAY 2001 DISCUSSION OF PERFORMANCE THEORY OF OPERATION The following discussion refers to the schematic in figure 2 below. A FET current source is used to bias a 6.3V 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 4.500V output. The gain is determined by the resistor networks R3 and R4: G=1 + R4/R3. The 6.3V zener diode is used because it is the most stable diode over time and temperature. 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 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. Figure 3 shows the proper connection of the VRE304 series voltage references with the optional trim resistor for initial error and the optional capacitor for noise reduction. The VRE304 reference has the ground terminal brought out on two pins (pin 4 and pin 7) 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 4 to the power supply ground and pin 7 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. Pay careful attention to the circuit layout to avoid noise pickup and voltage drops in the lines. VRE304 FIGURE 2 EXTERNAL CONNECTIONS + VIN 2 8 V TEMP OUT 3 6 + VOUT 10kΩ OPTIONAL FINE TRIM ADJUSTMENT OPTIONAL NOISE REDUCTION CAPACITOR VRE304 CΝ 1µF 7 4 5 FIGURE 3 REF. GND VRE304DS REV. D MAY 2001 FIGURE 3 MECHANICAL D D1 D2 INCHES DIM A B B1 MIN .115 .098 .046 .107 .009 .052 .397 .372 MAX .125 .102 .051 .113 .012 .058 .403 .380 MILLIMETER MIN 2.92 2.48 1.14 2.71 0.22 1.32 10.0 9.44 MAX 3.17 2.59 1.29 2.89 0.30 1.47 10.2 9.65 DIM D2 E E1 E2 P Q S INCHES MIN .018 .507 .397 .264 .085 .020 .045 MAX .023 .513 .403 .270 .095 .030 .055 MILLIMETER MIN 0.46 12.8 10.0 6.70 2.15 .508 1.14 MAX 0.58 13.0 10.2 6.85 2.41 .762 1.39 E2 E1 E C C1 C2 D PIN 1 IDENTIFIER D1 A Q BASE SEATING E1 P C1 C2 C B B1 FIGURE 4 S INCHES DIM A B B1 B2 C D D1 MIN .115 .018 .046 .098 .009 .397 .372 MAX .125 .022 .051 .102 .012 .403 .380 MILLIMETER MIN 2.92 .457 1.14 2.48 0.22 10.0 9.44 MAX 3.17 .558 1.29 2.59 0.30 10.2 9.65 DIM E E1 G1 L P Q S INCHES MIN .397 .264 .290 .195 .085 .055 .045 MAX .403 .270 .310 .215 .095 .065 .055 MILLIMETER MIN 10.0 6.70 7.36 4.95 2.15 1.39 1.14 MAX 10.2 6.85 7.87 5.46 2.41 1.65 1.39 VRE304DS REV. D MAY 2001 VRE304-6 Low Cost Precision Reference THALER CORPORATION • 2015 N. FORBES BOULEVARD • TUCSON, AZ. 8574 5 • (520) 882 -4000 FEATURES • 4.096 V OUTPUT ± 0.409 mV (.01%) PIN CONFIGURATION • TEMPERATURE DRIFT: 0.6 ppm/°C • LOW NOISE: 3µV p-p (0.1-10Hz) • INDUSTRY STD PINOUT- 8 PIN DIP OR SURFACE MOUNT PACKAGE •EXCELLENT LINE REGULATION: 6ppm/V Typ. • OPERATES ON +15V SUPPLY FIGURE 1 N/C +VIN TEMP GND 1 2 3 4 VRE304-6 8 7 6 5 NOISE REDUCTION REF. GND VOUT TRIM TOP VIEW DESCRIPTION The VRE304-6 is a low cost, high precision 4.096V reference. Packaged in the industry standard 8 pin DIP, the device is ideal for upgrading systems that use lower performance references. The device provides ultrastable +4.096V output with ±0.409 mV (.01%) initial accuracy and a temperature coefficient of 0.6 ppm/°C. This improvement in accuracy is made possible by a unique, patented 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 VRE304-6 series the most accurate reference available in the standard 8 pin DIP package. For enhanced performance, the VRE304-6 has an external trim option for users who want less than 0.01% initial error. For ultra low noise applications, an external capacitor can be attached between the noise reduction pin and the ground pin. A reference ground pin is provided to eliminate socket contact resistance errors. The VRE304-6 is recommended for use as a reference for 14, 16, or 18 bit D/A converters which require an external precision reference. The device is also ideal for calibrating scale factor on high resolution A/D converters. The VRE3046 offers superior performance over monolithic references. SELECTION GUIDE Initial Error mV 0.41 0.64 0.82 0.41 0.64 0.82 Model VRE304-6A VRE304-6B VRE304-6C VRE304-6J VRE304-6K VRE304-6L Temp. Coeff. ppm/°C 0.6 1.0 2.0 0.6 1.0 2.0 Temp. Range °C 0°C to +70°C 0°C to +70°C 0°C to +70°C -40°C to +85°C -40°C to +85°C -40°C to +85°C For package option add D for DIP or S for Surface Mount to end of model number. VRE304-6DS REV. D JUN 1999 ELECTRICAL SPECIFICATIONS Vps =+15V, T = 25°C, RL = 10KΩ unless otherwise noted. VRE304-6 B/K MAX MIN TYP MAX MIN MODEL PARAMETER ABSOLUTE RATINGS Power Supply Operating Temp. (A,B,C) Operating Temp. (J,K,L) Storage Temperature Short Circuit Protection OUTPUT VOLTAGE VRE304-6 (1) Temp. Sensor Voltage OUTPUT VOLTAGE ERRORS Initial Error Warmup Drift Tmin - Tmax (3) Long-Term Stability Noise (.1-10Hz) (4) OUTPUT CURRENT Range REGULATION Line Load OUTPUT ADJUSTMENT Range (5) (2) A/J MIN TYP C/L TYP MAX UNITS +13 0 -40 -65 +22 +70 +85 +150 Continuous +15 * * * * * * * * * * * * * * * * * * V °C °C °C * * 4.096 630 * * * * V mV 0.41 1 0.6 6 3 * * 2 0.64 3 1.0 * * 0.82 2.0 mV ppm ppm/ °C ppm/1000hrs µVpp ±10 * * mA 6 3 10 * * * * * * ppm/V ppm/mA 10 * * mV POWER SUPPLY CURRENTS VRE304-6 +PS NOTES: *Same as A/J Models. 5 7 * * * * mA 1. The temp. reference TC is 2.1mV/ °C 2. The specified values are without external trim. 3. The temperature coefficient is determined by the box method using the following formula: Vmax - Vmin T.C. = Vnominal x (Tmax-Tmin) x 106 4. The specified values are without the external noise reduction capacitor. 5. The specified values are unloaded. VRE304-6DS REV. D JUN 1999 TYPICAL PERFORMANCE CURVES VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE Temperature oC VRE304-6A Temperature oC VRE304-6B Temperature oC VRE304-6C VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE Temperature oC VRE304-6J Temperature oC VRE304-6K Temperature oC VRE304-6L QUIESCENT CURRENT VS. TEMP JUNCTION TEMP. RISE VS. OUTPUT CURRENT PSRR VS. FREQUENCY Temperature oC Output Current (mA) Frequency (Hz) VRE304-6DS REV. D JUN 1999 DISCUSSION OF PERFORMANCE THEORY OF OPERATION The following discussion refers to the schematic in figure 2 below. A FET current source is used to bias a 6.3V 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 4.096V output. The gain is determined by the resistor networks R3 and R4: G=1 + R4/R3. The 6.3V zener diode is used because it is the most stable diode over time and temperature. 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 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. Figure 3 shows the proper connection of the VRE304-6 series voltage references with the optional trim resistor for initial error and the optional capacitor for noise reduction. The VRE304-6 reference has the ground terminal brought out on two pins (pin 4 and pin 7) 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 4 to the power supply ground and pin 7 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. Pay careful attention to the circuit layout to avoid noise pickup and voltage drops in the lines. VRE304-6 FIGURE 2 EXTERNAL CONNECTIONS + VIN 2 8 V TEMP OUT 3 6 + VOUT 10k? OPTIONAL FINE TRIM ADJUSTMENT OPTIONAL NOISE REDUCTION CAPACITOR VRE304-6 CN 1µF 7 4 5 FIGURE 3 REF. GND VRE304-6DS REV. D JUN 1999 MECHANICAL SPECIFICATIONS FIGURE 3 INCHES DIM A B B1 C C1 C2 D MIN .110 .095 .021 .055 .012 .020 .395 MAX .120 .105 .027 .065 .020 .040 .405 MILLIMETER MIN MAX DIM D1 E E1 E2 P S INCHES MIN .372 .425 .397 .264 .085 .045 MAX .380 .435 .403 .270 .095 .055 MILLIMETER MIN 9.45 MAX 9.65 2.794 3.048 2.413 2.667 0.533 0.686 1.397 1.651 0.305 0.508 0.508 1.016 10.03 10.29 10.80 11.05 10.08 10.24 6.71 2.16 1.14 6.86 2.41 1.40 D D1 E2 E1 E 1 A P C1 B B1 C C2 S VRE304-6DS REV. D JUN 1999 MECHANICAL SPECIFICATIONS INCHES DIM A B B1 C C1 D D1 MIN .170 .095 .016 .008 .055 .395 .372 MAX .180 .105 .020 .011 .065 .405 .380 MILLIMETER MIN MAX DIM E E1 E2 G L P S INCHES MIN .425 .397 .264 .290 .175 .085 .045 MAX .435 .403 .270 .310 .225 .095 .055 MILLIMETER MIN MAX 4.318 4.572 2.413 2.667 0.406 0.508 0.203 0.279 1.397 1.651 10.03 10.29 9.45 9.65 10.80 11.05 10.08 10.24 6.71 7.36 4.46 2.16 1.14 6.86 7.87 5.72 2.41 1.40 D D1 E2 E1 E 1 A C1 L B B1 S C G P VRE304-4DS REV. D JUN 1999 VRE305 Low Cost Precision Reference THALER CORPORATION • 2015 N. FORBES BOULEVARD • TUCSON, AZ. 85745 • (520) 882-4000 FEATURES • 5.000 V OUTPUT ± 0.500 mV (.01%) • TEMPERATURE DRIFT: 0.6 ppm/°C • LOW NOISE: 3µV p-p (0.1-10Hz) • INDUSTRY STD PINOUT- 8 PIN DIP OR SURFACE MOUNT PACKAGE •EXCELLENT LINE REGULATION: 6ppm/V Typ. • OUTPUT TRIM CAPABILITY FIGURE 1 N/C +VIN TEMP GND 1 2 3 4 8 PIN CONFIGURATION NOISE REDUCTION REF. GND VOUT TRIM VRE305 TOP VIEW 7 6 5 DESCRIPTION The VRE305 is a low cost, high precision 5.0V reference. Packaged in the industry standard 8 pin DIP, the device is ideal for upgrading systems that use lower performance references. The device provides ultrastable +5.000V output with ±0.5000 mV (.01%) initial accuracy and a temperature coefficient of 0.6 ppm/°C. This improvement in accuracy is made possible by a unique, patented 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 VRE305 series the most accurate reference available in the standard 8 pin DIP package. For enhanced performance, the VRE305 has an external trim option for users who want less than 0.01% initial error. For ultra low noise applications, an external capacitor can be attached between the noise reduction pin and the ground pin. A reference ground pin is provided to eliminate socket contact resistance errors. The VRE305 is recommended for use as a reference for 14, 16, or 18 bit D/A converters which require an external precision reference. The device is also ideal for calibrating scale factor on high resolution A/D converters. The VRE305 offers superior performance over monolithic references. SELECTION GUIDE Initial Error mV 0.5 0.8 1.0 0.5 0.8 1.0 Model VRE305A VRE305B VRE305C VRE305J VRE305K VRE305L Temp. Coeff. ppm/°C 0.6 1.0 2.0 0.6 1.0 2.0 Temp. Range °C 0°C to +70°C 0°C to +70°C 0°C to +70°C -40°C to +85°C -40°C to +85°C -40°C to +85°C For package option add D for DIP or S for Surface Mount to end of model number. VRE305DS REV. D MAY 2001 ELECTRICAL SPECIFICATIONS Vps =+15V, T = 25°C, RL = 10kΩ unless otherwise noted. VRE305 B/K MAX MIN TYP MAX MIN MODEL PARAMETER ABSOLUTE RATINGS Power Supply Operating Temp. (A,B,C) Operating Temp. (J,K,L) Storage Temperature Short Circuit Protection OUTPUT VOLTAGE VRE305 (1) Temp. Sensor Voltage OUTPUT VOLTAGE ERRORS Initial Error Warmup Drift Tmin - Tmax (3) Long-Term Stability Noise (.1-10Hz) (4) OUTPUT CURRENT Range REGULATION Line Load OUTPUT ADJUSTMENT Range POWER SUPPLY CURRENTS VRE305 +PS NOTES: *Same as A/J Models. (5) (2) A/J MIN TYP C/L TYP MAX UNITS +13.5 0 -40 -65 +22 +70 +85 +150 Continuous +15 * * * * * * * * * * * * * * * * * * V °C °C °C * * 5.000 630 * * * * V mV 0.50 1 0.6 6 3 * * 2 0.80 3 1.0 * * 1.00 2.0 mV ppm ppm/°C ppm/1000hrs µVpp ±10 * * mA 6 3 10 * * * * * * ppm/V ppm/mA 10 * * mV 5 7 * * * * mA 1. The temp. reference TC is 2.1mV/°C 2. The specified values are without external trim. 3. The temperature coefficient is determined by the box method using the following formula: Vmax - Vmin T.C. = Vnominal x (Tmax-Tmin) x 106 4. The specified values are without the external noise reduction capacitor. 5. The specified values are unloaded. VRE305DS REV. D MAY 2001 TYPICAL PERFORMANCE CURVES VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE Temperature oC VRE305A Temperature oC VRE305B Temperature oC VRE305C VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE Temperature oC VRE305J Temperature oC VRE305K Temperature oC VRE305L QUIESCENT CURRENT VS. TEMP JUNCTION TEMP. RISE VS. OUTPUT CURRENT PSRR VS. FREQUENCY Temperature oC Output Current (mA) Frequency (Hz) VRE305DS REV. D MAY 2001 DISCUSSION OF PERFORMANCE THEORY OF OPERATION The following discussion refers to the schematic in figure 2 below. A FET current source is used to bias a 6.3V 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 6.3V zener diode is used because it is the most stable diode over time and temperature. 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 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. Figure 3 shows the proper connection of the VRE305 series voltage references with the optional trim resistor for initial error and the optional capacitor for noise reduction. The VRE305 reference has the ground terminal brought out on two pins (pin 4 and pin 7) 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 4 to the power supply ground and pin 7 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. Pay careful attention to the circuit layout to avoid noise pickup and voltage drops in the lines. VRE305 FIGURE 2 EXTERNAL CONNECTIONS + VIN 2 8 V TEMP OUT 3 6 + VOUT 10KΩ OPTIONAL FINE TRIM ADJUSTMENT OPTIONAL NOISE REDUCTION CAPACITOR VRE305 CN 1µF 7 4 5 FIGURE 3 REF. GND VRE305DS REV. D MAY 2001 FIGURE 3 MECHANICAL D D1 D2 INCHES DIM A B B1 MIN .115 .098 .046 .107 .009 .052 .397 .372 MAX .125 .102 .051 .113 .012 .058 .403 .380 MILLIMETER MIN 2.92 2.48 1.14 2.71 0.22 1.32 10.0 9.44 MAX 3.17 2.59 1.29 2.89 0.30 1.47 10.2 9.65 DIM D2 E E1 E2 P Q S INCHES MIN .018 .507 .397 .264 .085 .020 .045 MAX .023 .513 .403 .270 .095 .030 .055 MILLIMETER MIN 0.46 12.8 10.0 6.70 2.15 .508 1.14 MAX 0.58 13.0 10.2 6.85 2.41 .762 1.39 E2 E1 E C C1 C2 D PIN 1 IDENTIFIER D1 A Q BASE SEATING E1 P C1 C2 C B B1 FIGURE 4 S INCHES DIM A B B1 B2 C D D1 MIN .115 .018 .046 .098 .009 .397 .372 MAX .125 .022 .051 .102 .012 .403 .380 MILLIMETER MIN 2.92 .457 1.14 2.48 0.22 10.0 9.44 MAX 3.17 .558 1.29 2.59 0.30 10.2 9.65 DIM E E1 G1 L P Q S INCHES MIN .397 .264 .290 .195 .085 .055 .045 MAX .403 .270 .310 .215 .095 .065 .055 MILLIMETER MIN 10.0 6.70 7.36 4.95 2.15 1.39 1.14 MAX 10.2 6.85 7.87 5.46 2.41 1.65 1.39 VRE305DS REV. D MAY 2001 VRE306 Low Cost Precision Reference THALER CORPORATION • 2015 N. FORBES BOULEVARD • TUCSON, AZ. 85745 • (520) 882-4000 FEATURES • 6.000 V OUTPUT ± 0.600 mV (.01%) • TEMPERATURE DRIFT: 0.6 ppm/°C • LOW NOISE: 4µV p-p (0.1-10Hz) • INDUSTRY STD PINOUT- 8 PIN DIP OR SURFACE MOUNT PACKAGE •EXCELLENT LINE REGULATION: 6ppm/V Typ. • OUTPUT TRIM CAPABILITY FIGURE 1 N/C +VIN TEMP GND 1 2 3 4 8 PIN CONFIGURATION NOISE REDUCTION REF. GND VOUT TRIM VRE306 TOP VIEW 7 6 5 DESCRIPTION The VRE306 is a low cost, high precision 6.0V reference. Packaged in the industry standard 8 pin DIP, the device is ideal for upgrading systems that use lower performance references. The device provides ultrastable +6.000V output with ±0.6000 mV (.01%) initial accuracy and a temperature coefficient of 0.6 ppm/°C. This improvement in accuracy is made possible by a unique, patented 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 VRE306 series the most accurate reference available in the standard 8 pin DIP package. For enhanced performance, the VRE306 has an external trim option for users who want less than 0.01% initial error. For ultra low noise applications, an external capacitor can be attached between the noise reduction pin and the ground pin. A reference ground pin is provided to eliminate socket contact resistance errors. The VRE306 is recommended for use as a reference for 14, 16, or 18 bit D/A converters which require an external precision reference. The device is also ideal for calibrating scale factor on high resolution A/D converters. The VRE306 offers superior performance over monolithic references. SELECTION GUIDE Initial Error mV 0.6 1.2 0.6 1.0 1.2 Model VRE306A VRE306C VRE306J VRE306K VRE306L Temp. Coeff. ppm/°C 0.6 2.0 0.6 1.0 2.0 Temp. Range °C 0°C to +70°C 0°C to +70°C -40°C to +85°C -40°C to +85°C -40°C to +85°C For package option add D for DIP or S for Surface Mount to end of model number. VRE306DS REV. B MAY 2001 ELECTRICAL SPECIFICATIONS Vps =+15V, T = 25°C, RL = 10KΩ unless otherwise noted. VRE306 B/K MAX MIN TYP MAX MIN MODEL PARAMETER ABSOLUTE RATINGS Power Supply Operating Temp. (A,B,C) Operating Temp. (J,K,L) Storage Temperature Short Circuit Protection OUTPUT VOLTAGE VRE306 (1) Temp. Sensor Voltage OUTPUT VOLTAGE ERRORS Initial Error Warmup Drift Tmin - Tmax (3) Long-Term Stability Noise (.1-10Hz) (4) OUTPUT CURRENT Range REGULATION Line Load OUTPUT ADJUSTMENT Range POWER SUPPLY CURRENTS VRE306 +PS NOTES: *Same as A/J Models. (5) (2) A/J MIN TYP C/L TYP MAX UNITS +14 0 -40 -65 +16 +70 +85 +150 Continuous +15 * * * * * * * * * * * * * * * * * * V °C °C °C * * 6.000 630 * * * * V mV 0.60 1 0.6 6 4 * * 2 1.00 3 1.0 * * 1.20 2.0 mV ppm ppm/ °C ppm/1000hrs µVpp ±10 * * mA 6 3 10 * * * * * * ppm/V ppm/mA 10 * * mV 5 7 * * * * mA 1. The temp. reference TC is 2.1mV/ °C 2. The specified values are without external trim. 3. The temperature coefficient is determined by the box method using the following formula: Vmax - Vmin T.C. = Vnominal x (Tmax-Tmin) x 106 4. The specified values are without the external noise reduction capacitor. 5. The specified values are unloaded. VRE306DS REV. B MAY 2001 TYPICAL PERFORMANCE CURVES VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE Temperature oC VRE306A Temperature oC VRE306B Temperature oC VRE306C VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE Temperature oC VRE306J Temperature oC VRE306K Temperature oC VRE306L QUIESCENT CURRENT VS. TEMP JUNCTION TEMP. RISE VS. OUTPUT CURRENT PSRR VS. FREQUENCY Temperature oC Output Current (mA) Frequency (Hz) VRE306DS REV. B MAY 2001 DISCUSSION OF PERFORMANCE THEORY OF OPERATION The following discussion refers to the schematic in figure 2 below. A FET current source is used to bias a 6.3V 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 6.000V output. The gain is determined by the resistor networks R3 and R4: G=1 + R4/R3. The 6.3V zener diode is used because it is the most stable diode over time and temperature. 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 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. Figure 3 shows the proper connection of the VRE306 series voltage references with the optional trim resistor for initial error and the optional capacitor for noise reduction. The VRE306 reference has the ground terminal brought out on two pins (pin 4 and pin 7) 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 4 to the power supply ground and pin 7 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. Pay careful attention to the circuit layout to avoid noise pickup and voltage drops in the lines. VRE306 FIGURE 2 EXTERNAL CONNECTIONS + VIN 2 8 V TEMP OUT 3 6 + VOUT 10kW OPTIONAL FINE TRIM ADJUSTMENT OPTIONAL NOISE REDUCTION CAPACITOR VRE306 CN 1µF 7 4 5 FIGURE 3 REF. GND VRE306DS REV. B MAY 2001 MECHANICAL FIGURE 3 D D1 D2 INCHES DIM A B B1 MIN .115 .098 .046 .107 .009 .052 .397 .372 MAX .125 .102 .051 .113 .012 .058 .403 .380 MILLIMETER MIN 2.92 2.48 1.14 2.71 0.22 1.32 10.0 9.44 MAX 3.17 2.59 1.29 2.89 0.30 1.47 10.2 9.65 DIM D2 E E1 E2 P Q S INCHES MIN .018 .507 .397 .264 .085 .020 .045 MAX .023 .513 .403 .270 .095 .030 .055 MILLIMETER MIN 0.46 12.8 10.0 6.70 2.15 .508 1.14 MAX 0.58 13.0 10.2 6.85 2.41 .762 1.39 E2 E1 E C C1 C2 D PIN 1 IDENTIFIER D1 A Q BASE SEATING E1 P C1 C2 C B B1 FIGURE 4 S INCHES DIM A B B1 B2 C D D1 MIN .115 .018 .046 .098 .009 .397 .372 MAX .125 .022 .051 .102 .012 .403 .380 MILLIMETER MIN 2.92 .457 1.14 2.48 0.22 10.0 9.44 MAX 3.17 .558 1.29 2.59 0.30 10.2 9.65 DIM E E1 G1 L P Q S INCHES MIN .397 .264 .290 .195 .085 .055 .045 MAX .403 .270 .310 .215 .095 .065 .055 MILLIMETER MIN 10.0 6.70 7.36 4.95 2.15 1.39 1.14 MAX 10.2 6.85 7.87 5.46 2.41 1.65 1.39 VRE306DS REV. B MAY 2001 VRE310 Low Cost Precision Reference THALER CORPORATION • 2015 N. FORBES BOULEVARD • TUCSON, AZ. 85745 • (520) 882-4000 FEATURES • 10.000 V OUTPUT ± 1.000 mV (.01%) • TEMPERATURE DRIFT: 0.6 ppm/°C • LOW NOISE: 6µV p-p (0.1-10Hz) • INDUSTRY STD PINOUT- 8 PIN DIP OR SURFACE MOUNT PACKAGE •EXCELLENT LINE REGULATION: 6ppm/V Typ. • OUTPUT TRIM CAPABILITY FIGURE 1 N/C +VIN TEMP GND 1 2 3 4 8 PIN CONFIGURATION NOISE REDUCTION REF. GND VOUT TRIM VRE310 TOP VIEW 7 6 5 DESCRIPTION The VRE310 is a low cost, high precision 10.0V reference. Packaged in the industry standard 8 pin DIP, the device is ideal for upgrading systems that use lower performance references. The device provides ultrastable +10.000V output with ±1.000 mV (.01%) initial accuracy and a temperature coefficient of 0.6 ppm/°C. This improvement in accuracy is made possible by a unique, patented 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 VRE310 series the most accurate reference available in the standard 8 pin DIP package. For enhanced performance, the VRE310 has an external trim option for users who want less than 0.01% initial error. For ultra low noise applications, an external capacitor can be attached between the noise reduction pin and the ground pin. A reference ground pin is provided to eliminate socket contact resistance errors. The VRE310 is recommended for use as a reference for 14-, 16-, or 18-bit D/A converters which require an external precision reference. The device is also ideal for calibrating scale factor on high resolution A/D converters. The VRE310 offers superior performance over monolithic references. SELECTION GUIDE Initial Error mV 1.0 1.6 2.0 1.0 1.6 2.0 Model VRE310A VRE310B VRE310C VRE310J VRE310K VRE310L Temp. Coeff. ppm/°C 0.6 1.0 2.0 0.6 1.0 2.0 Temp. Range °C 0°C to +70°C 0°C to +70°C 0°C to +70°C -40°C to +85°C -40°C to +85°C -40°C to +85°C For package option add D for DIP or S for Surface Mount to end of model number. VRE310DS REV. D MAY 2001 ELECTRICAL SPECIFICATIONS Vps =+15V, T = 25°C, RL = 10KΩ unless otherwise noted. VRE310 B/K MAX MIN TYP MAX MIN MODEL PARAMETER ABSOLUTE RATINGS Power Supply Operating Temp. (A,B,C) Operating Temp. (J,K,L) Storage Temperature Short Circuit Protection OUTPUT VOLTAGE VRE310 (1) Temp. Sensor Voltage OUTPUT VOLTAGE ERRORS Initial Error Warmup Drift Tmin - Tmax (3) Long-Term Stability Noise (.1-10Hz) (4) OUTPUT CURRENT Range REGULATION Line Load OUTPUT ADJUSTMENT Range POWER SUPPLY CURRENTS VRE310 +PS NOTES: *Same as A/J Models. (5) (2) A/J MIN TYP C/L TYP MAX UNITS +13.5 0 -40 -65 +22 +70 +85 +150 Continuous +15 * * * * * * * * * * * * * * * * * * V °C °C °C * * 10.000 630 * * * * V mV 1.00 1 0.6 6 6 * * 2 1.60 3 1.0 * * 2.00 2.0 mV ppm ppm/°C ppm/1000hrs µVpp ±10 * * mA 3 3 10 * * * * * * ppm/V ppm/mA 20 * * mV 5 7 * * * * mA 1. The temp. reference TC is 2.1mV/°C 2. The specified values are without external trim. 3. The temperature coefficient is determined by the box method using the following formula: Vmax - Vmin T.C. = Vnominal x (Tmax-Tmin) x 106 4. The specified values are without the external noise reduction capacitor. 5. The specified values are unloaded. VRE310DS REV. D MAY 2001 TYPICAL PERFORMANCE CURVES VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE Temperature oC VRE310A Temperature oC VRE310B Temperature oC VRE310C VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE VOUT vs. TEMPERATURE Temperature oC VRE310J Temperature oC VRE310K Temperature oC VRE310L QUIESCENT CURRENT VS. TEMP JUNCTION TEMP. RISE VS. OUTPUT CURRENT PSRR VS. FREQUENCY Temperature oC Output Current (mA) Frequency (Hz) VRE310DS REV. D MAY 2001 DISCUSSION OF PERFORMANCE THEORY OF OPERATION The following discussion refers to the schematic in figure 2 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. 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 Figure 3 shows the proper connection of the VRE310 series voltage references with the optional trim resistor. The VRE310 reference has the ground terminal brought out on two pins (pin 4 and pin 7) 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 4 to the power supply ground and pin 7 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. Pay careful attention to the circuit layout to avoid noise pickup and voltage drops in the lines. VRE310 FIGURE 2 EXTERNAL CONNECTIONS + VIN 2 8 V TEMP OUT 3 6 + VOUT 10kΩ OPTIONAL FINE TRIM ADJUSTMENT OPTIONAL NOISE REDUCTION CAPACITOR VRE310 CN 1µF 7 4 5 FIGURE 3 REF. GND VRE310DS REV. D MAY 2001 FIGURE 3 MECHANICAL D D1 D2 INCHES DIM A B B1 MIN .115 .098 .046 .107 .009 .052 .397 .372 MAX .125 .102 .051 .113 .012 .058 .403 .380 MILLIMETER MIN 2.92 2.48 1.14 2.71 0.22 1.32 10.0 9.44 MAX 3.17 2.59 1.29 2.89 0.30 1.47 10.2 9.65 DIM D2 E E1 E2 P Q S INCHES MIN .018 .507 .397 .264 .085 .020 .045 MAX .023 .513 .403 .270 .095 .030 .055 MILLIMETER MIN 0.46 12.8 10.0 6.70 2.15 .508 1.14 MAX 0.58 13.0 10.2 6.85 2.41 .762 1.39 E2 E1 E C C1 C2 D PIN 1 IDENTIFIER D1 A Q BASE SEATING E1 P C1 C2 C B B1 FIGURE 4 S INCHES DIM A B B1 B2 C D D1 MIN .115 .018 .046 .098 .009 .397 .372 MAX .125 .022 .051 .102 .012 .403 .380 MILLIMETER MIN 2.92 .457 1.14 2.48 0.22 10.0 9.44 MAX 3.17 .558 1.29 2.59 0.30 10.2 9.65 DIM E E1 G1 L P Q S INCHES MIN .397 .264 .290 .195 .085 .055 .045 MAX .403 .270 .310 .215 .095 .065 .055 MILLIMETER MIN 10.0 6.70 7.36 4.95 2.15 1.39 1.14 MAX 10.2 6.85 7.87 5.46 2.41 1.65 1.39 VRE310DS REV. D MAY 2001