SUPPLY VOLTAGE MONITOR ZSM300 ISSUE 1 – NOVEMBER 1995 DEVICE DESCRIPTION FEATURES The ZSM300 is a three terminal under vo l ta ge mo ni t or ci rc ui t f or use i n microprocessor systems. The threshold voltage of the device has been set to 2.63 volts making it ideal for 3 volt circuits. • • • • • • • Included in the device is a precise voltage reference and a comparator with built in hysteresis to prevent erratic operation. The ZSM300 features an open collector output capable of sinking at least l0mA which only requires a single external resistor to interface to following circuits. • • SO8, SOT223 and TO92 packages Power on reset generator Automatic reset generation Low standby current Guaranteed operation from 1 volt Wide supply voltage range Internal clamp diode to discharge delay capacitor 2.63 volt threshold for 3 volt logic 20mV hysteresis prevents erratic operation APPLICATIONS Operation of the device is guaranteed from one volt upwards, from this level to the device threshold voltage the output is held low providing a power on reset function. Should the supply voltage, once established, at any time drop below the threshold level then the output again will pull low. • • • • • • The device is available in a TO92 package for through hole applications as well as SO8 and SOT223 for surface mount requirements. SCHEMATIC DIAGRAM 4-339 Microprocessor systems Computers Computer peripherals Instrumentation Automotive Battery powered equipment ZSM300 Power Dissipation TO92 SOT223 SO8 ABSOLUTE MAXIMUM RATING Input Supply Voltage Offstate Output Voltage Onstate Output Sink Current(Note 1) Clamp Diode Forward Current(Note 1) Operating Junction Temperature Operating Temperature Storage Temperature -1 to 10V 10V 780mW 2W(Note 2) 780mW(Note 2) Internally limited 100mA 150°C -40 to 85°C -55 to 150°C TEST CONDITIONS (Tamb=25°C for typical values, Tamb=-40 to 85°C for min/max values (Note3)) COMPARATOR MIN TYP. MAX. PARAMETER SYMBOL UNITS Threshold Voltage High state output (Vcc increasing) VIH 2.56 2.64 2.7 V Threshold Voltage Low state output (Vcc decreasing) VIL 2.56 2.62 2.7 V Hysteresis VH 0.01 0.02 0.05 V (Vcc=2.2V, Isink=8.0mA) 0.46 1.0 V (Vcc=2.2V, Isink=2.0mA) 0.15 0.4 V OUPUT Output sink saturation: VOL (Vcc=1.0V, Isink=0.1mA) Onstate output sink current (Vcc , Output=2.2V) Isink Offstate output leakage current (Vcc , Output=3V) Ioh Clamp diode forward voltage (If=10mA) Vf Propagation delay (Vin 3V to 2.2V, Rl=10k, Tamb=25°C) Td 10 0.6 0.25 V 27 60 mA 0.02 0.5 µA 1.2 1.5 V µs 2.5 TOTAL DEVICE Operating input voltage range Vcc Quiescent input current (Vcc=3V) Iq 1.0 to 6.5 V 125 190 µA Note: 1. Maximum package power dissipation must be observed. 2. Maximum power dissipation, for the SOT223 and SO8 packages, is calculated assuming that the device is mounted on a PCB measuring 2 inches square. 3. Low duty cycle pulse techniques are used during test to maintain junction temperatures as close to ambient as possible. 4-340 ZSM300 5 400 4 R =10K TA =25 °C (V) 500 85 °C 300 3 Output Voltage Input Current (µA) TYPICAL CHARACTERISTICS 200 -40 °C 25 °C 2 100 1 0 0 0 2 4 6 Input Voltage 8 10 0 2 4 3 Input Voltage Input Current vs. Input Voltage 50 1 (V) 5 (V) Output Voltage vs. Input Voltage Vin=2.4V RL =10K Vin (V) 30 3.0 2.4 2 -40 °C ' ' 4 25 °C 20 85 °C Vout (V) Sink Current (mA) 40 10 2 0 0 0 0.4 0.8 1.2 1.6 0 2.0 1 3 2 4 Time (µs) Output Saturation Voltage (V) Reset Delay Time Output Saturation Voltage vs. Sink Current 100 2.65 Vin=0V Upper Threshold 2.64 Threshold Voltage (V) Forward Current (mA) 80 60 85 °C 25 °C 40 -40 °C 20 0.4 0.8 1.2 1.6 2.62 Lower Threshold 2.61 2.60 -40 0 0 2.63 2.0 -20 0 20 40 60 80 100 Forward Voltage (V) Temperature (°C) Clamp Diode Forward Current vs. Voltage Threshold Voltage vs. Temperature 4-341 ZSM300 TIMING DIAGRAM Vcc Threshold Voltage 1V Output AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA Output Undefined Output Undefined APPLICATION CIRCUIT Note 4: A time delayed reset can be accomplished with the additional Cd. 1 T DY = RCd ln V TH (mpu) 1 − V in TDY =Time (Seconds) VTH =Microprocessor Reset Threshold Vin =Power Supply Voltage 4-342 ZSM300 CONNECTION DIAGRAMS SO8 Package Suffix – N8 SOT223 Top View Package Suffix – G Top View – Pin 4 floating or connected to pin 2 TO92 Package Suffix – C Bottom View ORDERING INFORMATION Part Number Package Part Mark ZSM300N8 SO8 ZSM300 ZSM300G SOT223 ZSM300 ZSM300C TO92 ZSM300 4-343