ASOT ASOTR ASOTR1 ASOTT ASOTT1 LSI/CSI UL ® LSI Computer Systems, Inc. 1235 Walt Whitman Road, Melville, NY 11747 (631) 271-0400 FAX (631) 271-0405 A3800 3, 4 AND 8 PIN AUTOMATIC SHUT-OFF TIMERS January 2002 ADVANCE INFORMATION DIP/SOIC FEATURES: • Minimizes external components and power consumption • Factory calibrated timer • Mask programmable from 2.5 minutes to 32 hours ASOTR1 and ASOTT1 APPLICATIONS Control of household appliances, heaters, lighting and AC motors. V DD 1 8 NC GND 2 7 NC OUT 3 6 NC IN 4 5 DUTY CYCLE IN 8-PIN VERSION DESCRIPTION The basic ASOT is a CMOS integrated circuit timer that can be mask programmed from 2.5 minutes to 32 hours as shown in Table 1. The output of the IC is used to turn on a 12V relay and has a duty cycle which can be mask programmed from 5% to 37.5% in 2.5% steps as shown in Table 2. The duty cycle can be selected to optimize operation for a particular relay coil. There are 5 different versions of the IC. The ASOT is a 3-Pin version housed in a TO-92 package. The application schematic is shown in Figure 2. When latching switch S1 is closed, the output turns on energizing relay L1 and keeping switch S1 closed. When the programmed time-out expires, the output turns off deenergizing relay L1 and causing switch S1 to open. The ASOTR is a 4-Pin version as shown in Figure 3. The output turns on in the same manner as in the 3-Pin version. If momentary switch S2 is closed, the timer resets and starts timing out again. The S2 input has an internal pull-up resistor. Every subsequent momentary switch closure resets the timer. As in the 3-Pin version, the output remains on until the timeout expires. The ASOTT is also a 4-Pin version as shown in Figure 4. In this version contacts C1 replace switch S1 and are not accessible. The application of power caused by closing TABLE 1 TABLE 2 Timeout Numbers 01 - 10 V DD GND OUT 1 ASOT 2 FIGURE 1. PACKAGE OPTIONS the momentary switch S2 causes the output to toggle on as in the 3-Pin version. If the momentary switch is closed again, the output toggles off causing contact C1 to open and power to be removed. The R2 input has an internal pull-up resistor. The default operaton of the output produces a double duty cycle for the first 10 milliseconds of output activation to increase the pull-in torque of the relay. The option to remove this feature is factory selectable in the ASOT (3-Pin), ASOTR (4-Pin) and ASOTT (4-Pin) versions. There are also two 8-Pin versions available which allow the user to change this feature. The ASOTR1 is the 8-Pin version used in the Figure 3 application and the ASOTT1 is the 8-Pin version used in the Figure 4 application. In both cases, the duty cycle input has an internal pull-up resistor. Tying the input to Vss removes the double duty cycle feature. 0h 12.5m 0h 15m 0h 17.5m 0h 20m 0h 22.5m 0h 25m 11 - 20 0h 30m 0h 35m 0h 37.5m 0h 40m 0h 45m 0h 50m 0h 52.5m 1h 0m 1h 10m 1h 15m 21 - 30 1h 20m 1h 30m 1h 40m 1h 45m 2h 0m 2h 20m 2h 30m 2h 40m 3h 0m 3h 20m 31 - 40 3h 30m 4h 0m 4h 40m 5h 0m 5h 20m 6h 0m 6h 40m 7h 0m 8h 0m 9h 0m 41 - 50 9h 20m 10h 0m 10h 40m 12h 0m 14h 0m 16h 0m 20h 0m 24h 0m 28h 0m 32h 0m 5 Duty Cycle Percentages 7.5 10 12.5 22.5 25 27.5 IN 4 4-PIN VERSION V DD GND OUT 3-PIN VERSION 0h 10m Duty Cycle Numbers 01 - 07 3 ASOTR and ASOTT Auto Shut-Off Times 0h 0h 0h 2.5m 5m 7.5m 08 - 14 7214-011702-1 SIP TO-92 30 15 17.5 20 32.5 35 37.5 ABSOLUTE MAXIMUM RATINGS: (All voltages referenced to VSS) SYMBOL VDD VIN TA TSTG Maximum Input Operating Temperature Storage Temperature VALUE +85 +5 to Vss - 0.3 0 to +85 -65 to +150 UNIT V V °C °C ELECTRICAL CHARACERISTICS: (All voltages referenced to Vss) PARAMETER Shunt Regulator Voltage Regulator Sink Current Supply Current Power-On-Reset POR Hysteresis SYMBOL VDD ISK IDD VPOR VHYS MIN 70 32 7 TYP 75 37 - MAX 80 10 370 42 12 UNIT V mA µA V V CONDITION VDD = 48V - IO IO IO FO SOD 70 50 20.5 - 21.8 47 50 23.11 - mA mA µA kHz ms Vo = 5V Vo = 3V Vo = VDD VDD > VPOR VSW ISC - 20 2.5 - V µA ASOTR, ASOTT ASOTR Positive Clamp Voltage VPC @Input Sink Current = 350µA Negative Clamp Voltage VNC @Input Sink Current = 350µA - - 4 V ASOTT - - 1 V ASOTT Duty Cycle Select Source Current @VIN = 0V - 20 - µA ASOTR1, ASOTT1 Output Driver - ON Output Driver - OFF Output Frequency Switch On Delay INPUT Switching Voltage Source Current @VIN = 0V IDC R1 D1 C1 D1 R1 S1 D2 L O A D AC S1 L1 V DD C1 D2 L O A D OUT Vss FIGURE 2. AC ASOT R2 * DUTY V DD CYCLE IN L1 C1 D3 OUT Vss FIGURE 4. ASOTT, ASOTT1 This input available only for ASOTT1 * R1 D1 S1 AC L O A D * DUTY V DD CYCLE IN OUT Vss S2 FIGURE 3. ASOTR, ASOTR1 This input available only for ASOTR1 * 7214-011702-2 L1 C1 D2 The information included herein is believed to be accurate and reliable. However, LSI Computer Systems, Inc. assumes no responsibilities for inaccuracies, nor for any infringements of patent rights of others which may result from its use.