MAX6576/MAX6577 SOT Temperature Sensors with Period/Frequency Output Pin DescriptionPINNAMEFUNCTION 1 VDD Positive Supply Voltage 2 GND Ground 3 N.C. No Connection. Connect pin to GND or leave open. 4, 5 TS1, TS0 Time-Select Pins. TS1 and TS0 set the temperature scale factor by connecting TS1 and TS0 to either VDD or GND. See Tables 1 and 2. Square-Wave Output with a Clock Period Proportional to Absolute Temperature (°K) (MAX6576) 6 OUT Square-Wave Output with a Clock Frequency Proportional to Absolute Temperature (°K) (MAX6577) Table 1. MAX6576 Time-Select PinTable 2. MAX6577 Time-Select PinConfigurationConfigurationTS1TS0SCALAR MULTIPLIER (μs/°K)TS1TS0SCALAR MULTIPLIER (Hz/°K) GND GND 10 GND GND 4 GND VDD 40 GND VDD 1 VDD GND 160 VDD GND 1/4 VDD VDD 640 VDD VDD 1/16 Note: The temperature, in °C, may be calculated as follows: Note: The temperature, in °C, may be calculated as follows: PERIOD(µs) T( C ° ) = − 273.15 K ° FREQUENCY(µs) T( C ° ) = − 273.15 K ° SCALAR MULTIPLIER(µs/ K ° ) SCALAR MULTIPLIER(µs/ K ° ) Detailed Description to the absolute temperature (°K) of the device (Figure 1). The MAX6576/MAX6577 low-cost, low-current (140μA The MAX6576 has a push/pull CMOS output with sharp typ) temperature sensors are ideal for interfacing with edges. The speed of the output square wave can be microcontrollers (μCs) or microprocessors (μPs). The selected by hard-wiring TS1 and TS0 as shown in Table 1. MAX6576 converts ambient temperature into a 50% One of four scaled output periods can be selected using dutycycle square wave with a period proportional to TS1 and TS0. absolute temperature. The MAX6577 converts ambient MAX6577 Characteristics temperature into a 50% duty-cycle square wave with a The MAX6577 temperature sensor converts temperature frequency proportional to absolute temperature. Time- to frequency. The output of the device is a free-running, select pins (TS1, TS0) permit the internal temperature- 50% duty-cycle square wave with a frequency that is pro- controlled oscillator (TCO) to be scaled by four preset portional to the absolute temperature (°K) of the device multipliers. The MAX6576/MAX6577 feature a single-wire (Figure 2). The MAX6577 has a push/pull CMOS output interface to minimize the number of port pins necessary with sharp edges. The speed of the output square wave for interfacing with a μP. can be selected by hard-wiring TS1 and TS0 as shown MAX6576 Characteristics in Table 2. One of four scaled output frequencies can be The MAX6576 temperature sensor converts temperature selected using TS1 and TS0. to period. The output of the device is a free-running, 50% duty-cycle square wave with a period that is proportional www.maximintegrated.com Maxim Integrated │ 4