2-30

TELCOM SEMICONDUCTOR, INC.

PRELIMINARY INFORMATION

Parameter

Test Conditions

Min

Typ

Max

Units

Supply Voltage

4.5

—

18

V

Supply Current

—

300

600

µA

Output Resistance

Output High or Low

—

—

75

Ω

Output Current

—

—

25

mA

—

—

10

mA

Absolute Accuracy

At trip point

T – 3

T

T + 3

°C

Trip Point Hysteresis

3.5

5

6.5

°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

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 main-

tains the output high until measured temperature is 5

°C

lower than the trip point setting.

The TC626VZB (TO-92 package) has a maximum out-

put 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.

ABSOLUTE MAXIMUM RATINGS*

TO-92 ........................................................... 440mW

TO-220 ............................................................ 1.6mW

Supply Voltage ............................................................ 20V

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.

SET POINT

(SET POINT – 5

°C)

OUTPUT

Figure 1. TC626 Operation

TEMPERATURE LIMIT SWITCH

TC626