NTE999M Integrared Circuit Programmable Precision Reference Description: The NTE999M integrated circuit is a three–terminal programmable shunt regulator. This monolithic IC voltage reference operates as a low temperature coefficient zener which is programmable from Vref to 36 volts with two external resistors. This device exhibits a wide operating current range of 1.0 to 100mA with a typical dynamic impedance of 0.22Ω. The characteristics of this reference make it an excellent replacement for zener diodes in many applications such as digital voltmeters, power supplies, and op amp circuitry. The 2.5 volt reference makes it convenient to obtain a stable reference from 5.0 volt logic supplies, and since the NTE999M operates as a shunt regulator, it can be used as either a positive or negative voltage reference. Features: D Programmable Output Voltage to 36 Volts D Voltage Reference Tolerance: ±1.0% D Low Dynamic Output Impedance: 0.22Ω Typical D Sink Current Capability of 1.0 to 100mA D Equivalent Full Range Temperature Coefficient of 50ppm/°C Typical D Temperature Compensated for Operation over Full Rated Operating Temperature Range D Low Output Noise Voltage. Absolute Maximum Ratings: (TA = 0° to +70°C, unless otherwise noted.) Cathode to Anode Voltage, VKA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37V Cathode Current Range, Continuous, IK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –100 to +150mA Reference Input Current Range, Continuous, Iref . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.05 to +10mA Total Power Dissipation (TA = +25°C), PD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 725mW Derate Above 25°C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.8mW/°C Operating Junction Temperature, TJ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +150°C Operating Ambient Temperature Range, TA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0° to +70°C Storage Temperature Range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –65° to +150°C Thermal Resistance, Junction–to–Ambient, RthJA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178°C/W Thermal Resistance, Junction–to–Case, RthJC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83°C/W Lead Temperature (During Soldering, 1/16” from case for 10sec), TL . . . . . . . . . . . . . . . . . . . +260°C Recommended Operating Conditions Cathode to Anode Voltage, VKA Cathode Current, IK Min Vref 1.0 Max 36 100 Unit V mA Electrical Characteristics (TA = +25°C unless otherwise noted) Characteristic Reference Input Voltage VKA = Vref, IK = 10mA TA = +25°C Reference Input Voltage Deviation Over Temperature Range (Note 1, 2) VKA = Vref, IK = 10mA Ratio of Change in Reference Input Voltage to Change in Cathode to Anode Voltage IK = 10mA, ∆VKA = 10V to Vref ∆VKA = 36V to 10V Reference Input Current IK = 10mA, R1 = 10k, R2 = ∞ TA = +25°C TA = Tlow to Thigh (Note 1) Symbol Min Typ Max Unit Vref 2.470 2.495 2.520 V ∆Vref – 3.0 17 mV ∆Vref ∆VKA mV/V – – –1.4 –1.0 –2.7 –2.0 – – 1.8 – 4.0 5.2 ∆Iref – 1.8 4.0 µA Imin – 0.5 1.0 mA Ioff – 2.6 1000 nA |Zka| – 0.22 0.5 Ω µA Iref Reference Input Current Deviation Over Temperature Range (Note 1) IK = 10mA, R1 = 10k, R2 = ∞ Minimum Cathode Current for Regulation VKA = Vref Off–State Cathode Current VKA = 36V, Vref = 0V Dynamic Impedance (Note 3) VKA = Vref, ∆IK = 1.0mA to 100mA f ≤ 1.0kHz Note 1: Tlow = 0°C, Thigh = +70°C Note 2: The deviation parameter ∆Vref is defined as the differences between the maximum and minimum values obtained over the full operating ambient temperature range that applies. ∆Vref = VrefMax –VrefMin ∆TA = T2–T1 Note 2: (cont’d) The average temperature coefficient of the reference input voltage, α Vref, is defined as: ∆Vref α Vref ppm Vref @ 25°C x 106 ∆Vref x 106 = = ° ∆TA (Vref @ 25°C) ∆TA C α Vref can be positive or negative depending on whether Vref Min or Vref Max occurs at the lower ambient temperature. ∆VKA ∆IK When the device is programmed with two external resistors, R1 and R2, the total dynamic impedance of the circuit is defined as: Note 3: The dynamic impedance Zka is defined as: |Zka| = |Zka’| ≈ |Zka| 1+ R1 R2 Pin Connection Diagram Cathode 1 8 Reference Anode 2 7 Anode Anode 3 6 Anode N.C. 4 5 N.C. 8 5 .256 (6.52) Max 1 4 .300 (7.62) .393 (10.0) Max .150 (3.81) .100 (2.54) .070 (1.77) Min .300 (7.62)