SNOSBI2C June   1999  – September 2015 LM231 , LM331

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Description continued
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Dissipation Ratings
    7. 7.7 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
      1. 8.1.1 Detail of Operation, Functional Block Diagram
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
    4. 8.4 Device Functional Modes
  9. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Simplified Voltage-to-Frequency Converter
      2. 9.1.2 Principles of Operation
    2. 9.2 Typical Applications
      1. 9.2.1 Basic Voltage-to-Frequency Converter
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
        3. 9.2.1.3 Application Curve
      2. 9.2.2 Precision V-To-F Converter
    3. 9.3 System Examples
      1. 9.3.1 F-to-V Converters
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Related Links
    2. 12.2 Community Resources
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

7 Specifications

7.1 Absolute Maximum Ratings(2)(1)(1)

MIN MAX UNIT
Supply Voltage, VS 40 V
Output Short Circuit to Ground Continuous
Output Short Circuit to VCC Continuous
Input Voltage −0.2 +VS V
Lead Temperature (Soldering, 10 sec.) PDIP 260 °C
(1) If Military/Aerospace specified devices are required, please contact the TI Sales Office/Distributors for availability and specifications.
(2) Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

7.2 ESD Ratings

VALUE UNIT
V(ESD) Electrostatic discharge Human body model (HBM), per ANSI/ESDA/JEDEC JS-001(1)(2) ±500 V
(1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
(2) Human body model, 100 pF discharged through a 1.5-kΩ resistor.

7.3 Recommended Operating Conditions

MIN MAX UNIT
Operating Ambient Temperature  LM231, LM231A −25 85 °C
 LM331, LM331A 0 70 °C
Supply Voltage, VS(1) 4 40 V
(1) All voltages are measured with respect to GND = 0 V, unless otherwise noted.

7.4 Thermal Information

THERMAL METRIC(1) LM312, LM331 UNIT
P (PDIP)
8 PINS
RθJA Junction-to-ambient thermal resistance 100 °C/W
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application report, SPRA953.

7.5 Electrical Characteristics

All specifications apply in the circuit of Figure 16, with 4.0 V ≤ VS ≤ 40 V, TA = 25°C, unless otherwise specified.
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
VFC Non-Linearity (1) 4.5 V ≤ VS ≤ 20 V ±0.003 ±0.01 % Full-Scale
TMIN ≤ TA ≤ TMAX ±0.006 ±0.02 % Full-Scale
VFC Non-Linearity in Circuit of Figure 14 VS = 15 V, f = 10 Hz to 11 kHz ±0.024 ±0.14 %Full-Scale
Conversion Accuracy Scale Factor (Gain)   LM231, LM231A VIN = −10 V, RS = 14 kΩ 0.95 1 1.05 kHz/V
  LM331, LM331A 0.9 1 1.1 kHz/V
Temperature Stability of Gain   LMx31 TMIN ≤ TA ≤ TMAX
4.5 V ≤ VS ≤ 20 V		 ±30 ±150 ppm/°C
  LMx31A ±20 ±50 ppm/°C
Change of Gain with VS 4.5 V ≤ VS ≤ 10 V 0.01 0.1 %/V
10 V ≤ VS ≤ 40 V 0.006 0.06 %/V
Rated Full-Scale Frequency VIN = −10 V 10.0 kHz
Gain Stability vs. Time (1000 Hours) TMIN ≤ TA ≤ TMAX ±0.02 % Full- Scale
Over Range (Beyond Full-Scale) Frequency VIN = −11 V 10%
 INPUT COMPARATOR
Offset Voltage ±3 ±10 mV
  LM231/LM331 TMIN ≤ TA ≤ TMAX ±4 ±14 mV
  LM231A/LM331A TMIN ≤ TA ≤ TMAX ±3 ±10 mV
Bias Current −80 −300 nA
Offset Current ±8 ±100 nA
Common-Mode Range TMIN ≤ TA ≤ TMAX −0.2 VCC − 2 V
 TIMER
Timer Threshold Voltage, Pin 5 0.63 × VS 0.667 × VS 0.7 × VS
Input Bias Current, Pin 5 VS = 15 V
  All Devices 0V ≤ VPIN 5 ≤ 9.9 V ±10 ±100 nA
  LM231/LM331 VPIN 5 = 10 V 200 1000 nA
  LM231A/LM331A VPIN 5 = 10 V 200 500 nA
VSAT PIN 5 (Reset) I = 5 mA 0.22 0.5 V
 CURRENT SOURCE (PIN 1)
Output Current   LM231, LM231A RS = 14 kΩ, VPIN 1 = 0 126 135 144 μA
  LM331, LM331A 116 136 156 μA
Change with Voltage 0V ≤ VPIN 1 ≤ 10 V 0.2 1 μA
Current Source OFF Leakage   LM231, LM231A, LM331, LM331A 0.02 10 nA
  All Devices TA = TMAX 2 50 nA
Operating Range of Current (Typical) (10 to 500) μA
 REFERENCE VOLTAGE (PIN 2)
  LM231, LM231A 1.76 1.89 2.02 VDC
  LM331, LM331A 1.7 1.89 2.08 VDC
Stability vs. Temperature ±60 ppm/°C
Stability vs. Time, 1000 Hours ±0.1%
 LOGIC OUTPUT (PIN 3)
  VSAT I = 5 mA 0.15 0.5 V
I = 3.2 mA (2 TTL Loads),
TMIN ≤ TA ≤ TMAX		 0.1 0.4 V
  OFF Leakage ±0.05 1 μA
 SUPPLY CURRENT
LM231, LM231A VS = 5 V 2 3 4 mA
VS = 40 V 2.5 4 6 mA
LM331, LM331A VS = 5 V 1.5 3 6 mA
VS = 40 V 2 4 8 mA
(1) Non-linearity is defined as the deviation of fOUT from VIN × (10 kHz/−10 VDC) when the circuit has been trimmed for zero error at 10 Hz and at 10 kHz, over the frequency range 1 Hz to 11 kHz. For the timing capacitor, CT, use NPO ceramic, Teflon®, or polystyrene.

7.6 Dissipation Ratings

VALUE UNIT
Package Dissipation at 25°C(1) 1.25 W
(1) The absolute maximum junction temperature (TJmax) for this device is 150°C. The maximum allowable power dissipation is dictated by TJmax, the junction-to-ambient thermal resistance (θJA), and the ambient temperature TA, and can be calculated using the formula PDmax = (TJmax - TA) / θJA. The values for maximum power dissipation will be reached only when the device is operated in a severe fault condition (e.g., when input or output pins are driven beyond the power supply voltages, or the power supply polarity is reversed). Obviously, such conditions should always be avoided.

7.7 Typical Characteristics

(All electrical characteristics apply for the circuit of Figure 16, unless otherwise noted.)
LM231 LM331 00568025.png
Figure 1. Non-Linearity Error as Precision V-to-F Converter (Figure 16)
LM231 LM331 00568027.png
Figure 3. Non-Linearity Error vs. Power Supply Voltage
LM231 LM331 00568029.png
Figure 5. VREF vs. Temperature
LM231 LM331 00568031.png
Figure 7. 100 kHz Non-Linearity Error (Figure 17)
LM231 LM331 00568033.png
Figure 9. Input Current (Pins 6,7) vs. Temperature
LM231 LM331 00568035.png
Figure 11. Output Saturation Voltage vs. IOUT (Pin 3)
LM231 LM331 00568026.png
Figure 2. Non-Linearity Error
LM231 LM331 00568028.png
Figure 4. Frequency vs. Temperature
LM231 LM331 00568030.png
Figure 6. Output Frequency vs. VSUPPLY
LM231 LM331 00568032.png
Figure 8. Non-Linearity Error (Figure 14)
LM231 LM331 00568034.png
Figure 10. Power Drain vs. VSUPPLY
LM231 LM331 00568036.png
Figure 12. Non-Linearity Error, Precision F-to-V Converter (Figure 19)