DATASHEET SEARCH SITE | WWW.ALLDATASHEET.COM
Document overview
- Manufacturer or author: Provided By ALLDATASHEET.COM(FREE DATASHEET DOWNLOAD SITE)
- PDF pages: 4
Technical content
consumer and industrial products requiring low cost and high accuracy.
3 Seconds — Liquid ‘SENSORS
8 Seconds — Air
Figure 1. Base-Emitter Voltage versus Ambient Temperature
- All dewices within any one group or package will be matched for Vge to the tolerance identified in the electrical characteristics table. Each
device will be labeled with the mean Vge value for that group.
- All devices within an individual group, as descnbed in Note 1, will track within the specified temperature accuracy. This includes vanations.
- The Tc as defined by a least-square linear regression for VE versus temperature over the range — 40 to +150°C for a nominal VgE of 896
mV at 25°C. For other nominal VBE values the value of the Tc must be adjusted for the dependence of the Tc on VBE (see Note 4).
- For nominal VBE at 25°C other than 595 mV, the Tc must be corrected using the equation Tc = ~2.265 + 0.003 (Vg - 595) where Vge Is
in mV and the Tg is inmV/*°C, The accuracy of this Tg 1s typically +0.01 mV/*C.
- For maximum temperature accuracy, Ic should not exceed 2 mA. (See Figure 2)
8 LI HN eT gp Pf aA
Figure 2. Base-Emitter Voltage versus Figure 3. Temperature Coefficient versus
MT$102 MTS103 MTS105 a He tH get Be HH PRE g [i ttTrirint ts Sd
2 CON sf SA
J 77 tr rt TiN | g Pp Pry Ree eT anf a — Yo ets TS wtt|tTi Tt tT Tt | = P= Cri rrr errr tf PP PP PP tT | -40-2 0 2 © 6 80 «100 «120: «140160 —40 0 40 80 120 ‘TEMPERATURE (°C) ‘Ta, AMBIENT TEMPERATURE (°C) Figure 4, Linearity Error versus Temperature Figure 5. VBE versus Ambient Temperature APPLICATIONS INFORMATION The base and collector leads of the device should be connected together in the operating cirouit (pins 2 and 3). They are not internally connected. AN Vee The following example describes how to determine the 2. Determine the VpE value at extremes, - 40°C and VBE versus temperature relationship for a typical shipment of 4+150°C: various VBE groups. Vpecta) = VBE(25°C) + (To}(Ta - 25°C) where EXAMPLE: Vge(Ta) = value of VBE at desired temperature. . 3. Plot the VBE versus Ta curve using two Vge values: Given — Customer receives a shipment of MTS102 de- Vpe (- 40°C), VBE(25°C), or VBE(+150°C) vices. The shipment consists of three groups of different 4. Given any measured Ve, the value of TA (to the accu- nominal VBE values. racy value specified: MTS102 ~ +2°C, MTS103 - Group 1: VBE (nom) = 595 mV 435°C, MTS105 ~ + 6°C) can be read {rom Figure 5 See SuSE (rom) = sem or calculated from equation 2. roup ® WBE - . Higher temperature accuracies can be achieved if the Find — VBE versus temperature Relationship, collector current, Ic, is controlled to react in accor- dance with and to compensate for the linearity error. 1. Determine vaiue of Tc: Using this concept, practical circuits have been built in a. If VBE (nom) = 595 mV, Tc = -2.265 mV/°C from the which aliow these sensors to yield accuracies within b. If VBE (nom) is less than or greater than 595 mV de- termine T¢ from the relationship described in Note 4. Reference: “Transistors—A Hot Tip for Accurate Temperature Te = -2.265 + 0.0033 (VBE — 595) or see Figure 3. Sensing,” Pat O'Neil and Carl Dernngton, Electronics 1979. 2-104 Motorola Sensor Device Data MH 6367255 0088913 342