1 TC626* * PATENTED TEMPERATURE LIMIT SWITCH 2 FEATURES GENERAL DESCRIPTION ■ ■ ■ ■ ■ The TC626 is a temperature limit detector that notifies the system when measured temperature is above the factory-programmed setting. It is designed to replace mechanical (bimetal) temperature limit switches and offers increased ruggedness, higher reliability and greater setpoint accuracy. It requires no external components. The TC626 operates over a – 55°C to +125°C temperature range. It is available in a TO-92 package, which is ideal for ambient temperature sensing applications. It is also available in a TO-220-3 package for heatsink temperature measurement applications. Requires No External Components On-Chip Temperature Sensing TO-220 package for "Hot Spot" Mounting 50mA Output Signal TO-220 Package (TC626VAB) TO-92 Package for Direct Circuit Board Mounting APPLICATIONS ■ ■ ■ ■ ■ Vibration-Immune Temperature Sensing Fan Speed Control Circuits System Overtemperature Shutdown Advanced Thermal Warning Consumer Products SYSTEM OVERTEMPERATURE PROTECTION 5V TO 18V PIN 1 SWITCHES 'HIGH' IF TEMPERATURE GOES ABOVE THE PRESET VALUE. 2 NC 1 SYSTEM POWER TC626 RELAY 3 NC = NORMALLY CLOSED PIN CONFIGURATIONS TO-220-3 TO-92-3 1 2 3 TC626xxxVAB 4 ORDERING INFORMATION Part Number* Temperature Package TC626040VAB TC626040VZB TC626050VAB TC626050VZB TC626080VAB TC626080VZB TC626090VAB TC626090VZB TC626100VAB TC626100VZB TO-220-3 TO-92-3 TO-220-3 TO-92-3 TO-220-3 TO-92-3 TO-220-3 TO-92-3 TO-220-3 TO-92-3 3 Range – 55°C to +125°C – 55°C to +125°C – 55°C to +125°C – 55°C to +125°C – 55°C to +125°C – 55°C to +125°C – 55°C to +125°C – 55°C to +125°C – 55°C to +125°C – 55°C to +125°C *Trip-point temperature is designated as follows: Part numbers are TC626xxxVAB or TC626VZB, where xxx = trip-point tempeature in °C. For high volume applications requiring different trip-points, contact factory. 5 6 7 TC626xxxVZB 1 2 3 OUTPUT VDD GROUND OUTPUT VDD GROUND 1 2 3 8 TC626-6 TELCOM SEMICONDUCTOR, INC. 8/23/96 2-29 PRELIMINARY INFORMATION TEMPERATURE LIMIT SWITCH TC626 ABSOLUTE MAXIMUM RATINGS* Package Power Dissipation (TA ≤ 70°C) TO-92 ...........................................................440mW TO-220 ............................................................1.6mW Supply Voltage ............................................................20V Input Voltage Any Input ...... (GND – 0.3V) to (VDD + 0.3V) Operating Temperature ......................... – 55°C to +125°C Maximum Junction Temperature ........................... +150°C Storage Temperature ............................ – 65°C to +150°C Lead Temperature (Soldering, 10 sec) ................. +300°C *Stresses above those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only and functional operation of the device at these or any other conditions above those indicated in the operation sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS: VDD = +5V and TA = – 55°C to +125°C, unless otherwise specified. Parameter Supply Voltage Supply Current Output Resistance Output Current Absolute Accuracy Trip Point Hysteresis Test Conditions Output High or Low Source/Sink, VCC = 18V Source/Sink, VCC = 4.5V At trip point Min Typ Max Units 4.5 — — — — T–3 3.5 — 300 — — — T 5 18 600 75 25 10 T+3 6.5 V µA Ω mA mA °C °C TelCom Semiconductor reserves the right to make changes in the circuitry or specifications detailed in this manual at any time without notice. Minimums and maximums are guaranteed. All other specifications are intended as guidelines only. TelCom Semiconductor assumes no responsibility for the use of any circuits described herein and makes no representations that they are free from patent infringement. DETAILED DESCRIPTION The TC626 output maintains a logic low state when measured temperature is below the factory-programmed setting. As temperature rises, the output is driven active to a high level [VDD – (IOUT)(ROUT)] when temperature equals the setpoint value ±3°C. Built-in hysteresis prevents output "chattering" when measured temperature is at (or near) the trip point (Figure 1). As temperature falls through the trip point, hysteresis maintains the output high until measured temperature is 5°C lower than the trip point setting. The TC626VZB (TO-92 package) has a maximum output current of 10mA while the TC626VAB has a maximum output current of 50mA. Care must be taken to observe these output current limits as output currents in excess of those stated will cause device self-heating resulting in erroneous temperature measurements. 2-30 SET POINT (SET POINT – 5°C) OUTPUT Figure 1. TC626 Operation TELCOM SEMICONDUCTOR, INC.