VOLTAGE DETECTOR Introduction (General Description) EC9518C/ EC9519C Applications The EC9518C / 9519C Series is a highprecision voltage detector developed using CMOS process. The detection voltage is fixed internally with an accuracy of ±2.0 %. A time delayed reset can be accomplished with the addition of an external capacitor. Two output Power supply monitor for portable equipment forms, N-channel open-drain and CMOS output, are available. Power monitor and reset for CPUs and Features Packages Ultra-low current consumption such as electronic organizers, notebook PCs, cellular phones, digital cameras Constant voltage power monitor for cameras, communication equipment and video equipment microcomputers SOT-23-3 1.0 mA typ. (VDD=2.0 V) 1.1 mA typ. (VDD=3.5 V) High-precision detection voltage ±2.0 % Pin Assignment COperating voltage range 2.0 V to 6.0 V Detection voltage 2.2 V to 3.1 V (0.1 V step) Hysteresis characteristics 5 % typ. Two output forms: CMOS output active “L” Open-drain output active “L” E-CMOS Corp.（http://www.ecmos.com.tw） NO SYMBOL 1 OUT VOLTAGE DETECTION PIN 2 VSS GROUND PIN 3 VDD VOLTAGE INPUT PIN Page 1 / 9 DESCRITION 3H02N-Rev. P001 VOLTAGE DETECTOR EC9518C/ EC9519C Block Diagrams CMOS OUTPUT（EC9519C） OPEN DRAIN（EC9518C） Ordering Information PART NUMBER MARKING ID EC9518C XXB1R 18CXX LLLLL EC9519C XXB1R 19CXX LLLLL E-CMOS Corp.（http://www.ecmos.com.tw） Marking Information XX：Voltage Detection LLLLL：Lot No Page 2 / 9 PACKAGE PACKING TYPE SOT23-3 TAPE / REEL SOT23-3 TAPE / REEL 3H02N-Rev. P001 VOLTAGE DETECTOR EC9518C/ EC9519C Absolute Maximum Ratings PARAMETER SYMBOL POWER SUPPLY VOLTAGE VDD - VSS CD PIN INPUT VOLTAGE RATING UNIT 8 V VCD VSS -0.3 TO VDD +0.3 V OUTPUT VOLTAGE VOUT VSS -0.3 TO VDD +0.3 V OUTPUT CURRENT IOUT 4 mA POWER DISSIPATION PD SOT23 -5 150 mW OPERATING TEMPERATURE TOPR -40 TO +85 ℃ STORAGE TEMPERATURE TSTG -40 TO +125 ℃ JUNCTION TEMPERATURE Tj(max) 150 ℃ JUNCTION TO AMBIENT THERMAL RESISTANCE θja 347 ℃/W θjc 148 ℃/W JUNCTION TO CASE THERMAL RESISTANCE Electrical Characteristics CMOS output products (Ta=25°C unless otherwise specified) Parameter Symbol Conditions Detection voltage -VDET -- Hysteresis width VHYS -- Current consumption ISS VDD=4V Operating voltage VDD -- IOUT X 0.98 VDD= 2.4V P-channel VDS=VDD-0.5V VDD=4.8 V Delay time td E-CMOS Corp.（http://www.ecmos.com.tw） Typ -VDET(S) N-channel VDS=0.5V Output Current of output transistor Min Input Signal Ramp=3V/ms Page 3 / 9 -VDET Max -VDET(S) X 1.02 Unit Test circuit V 1 V 1 -VDET -VDET -VDET X0.03 X0.05 X0.08 -- 4.5 6.5 uA 2 2.0 -- 6.0 V 1 2.88 4.98 -- mA 3 1.43 2.39 -- mA 5 --- --- us 4 200 3H02N-Rev. P001 VOLTAGE DETECTOR EC9518C/ EC9519C Test circuit 1. 2. 3. 4. 5. E-CMOS Corp.（http://www.ecmos.com.tw） Page 4 / 9 3H02N-Rev. P001 VOLTAGE DETECTOR EC9518C/ EC9519C Timing chart 1. CMOS active low output 2. Nch open-drain active low output Note：For values of VDD less than minimum operating voltage, values of OUT terminal output is free of the shaded region. E-CMOS Corp.（http://www.ecmos.com.tw） Page 5 / 9 3H02N-Rev. P001 VOLTAGE DETECTOR EC9518C/ EC9519C Definition of Technical Terms 1. Detection voltage (-VDET) Detection voltage -VDET is a voltage at which the output turns to low. This detection voltage varies slightly among products of the same specification. The variation of detection voltage between the specified minimum [(-VDET) min.] and maximum [(-VDET) max.] is called the detection voltage range (See Figure A). 2. Release voltage (+VDET) Release voltage +VDET is a voltage at which the output turns to high. This release voltage varies slightly among products of the same specification. The variation of release voltage between the specified minimum [(+VDET) min.] and maximum [(+VDET) max.] is called the release voltage range (See B). FIGURE A FIGURE B 3. Hysteresis width (VHYS) Hysteresis width is the voltage difference between the detection voltage and the release voltage. The existence of the hysteresis width avoids malfunction caused by noise on input signal. 4. Delay time (td) Delay time is a time internally measured from the instant at which VDD pin exceeds the release voltage (+VDET) to the point at which the output of the OUT pin inverts. E-CMOS Corp.（http://www.ecmos.com.tw） Page 6 / 9 3H02N-Rev. P001 VOLTAGE DETECTOR EC9518C/ EC9519C 5. Short-circuit current Short-circuit current refers to the current which flows instantaneously at the time of detection and release of a voltage detector. Short-circuit current is large in CMOS output products, and small in N channel open-drain output products. 6. Oscillation In applications where a resistor is connected to the voltage detector input as shown in Figure , taking a CMOS active low product for example, the short-circuit current, which flows at release when the output goes from low to high, causes a voltage drop equal to [short-circuit current] × [input resistance] across the resistor. When the input voltage falls below the detection voltage -VDET as a result, the output voltage goes to low level. In this state, the short-circuit current stops and its resultant voltage drop disappears, and the output goes from low to high. Short-circuit current again starts flowing, a voltage drop appears, and oscillation is finally induced by repeating the process. Following is an example for bad implementation: input voltage divider for a CMOS output product. Standard Circuit E-CMOS Corp.（http://www.ecmos.com.tw） Page 7 / 9 3H02N-Rev. P001 VOLTAGE DETECTOR EC9518C/ EC9519C Application Circuit Examples 1. Microcomputer reset circuits With the EC9519CXX Series which has a low operating voltage, a high-precision detection voltage and hysteresis characteristic, the reset circuits shown in Figures A to B can be easily constructed. (Nch open-drain output products only) Figures B Figures A 2. Change of detection voltage In Nch open-drain output products of the EC9508CXX Series, detection voltage can be changed using resistance dividers or diodes as shown in Figures C and D. Hysteresis width is also changed. Figures C Figures D Note1: If RA and RB are large, the hysteresis width may also be larger than the value given by the equation above due to short-circuit current (which flows slightly in an N channel open-drain product). Note2: RA should be 75k Ω or less to prevent oscillation. E-CMOS Corp.（http://www.ecmos.com.tw） Page 8 / 9 3H02N-Rev. P001 VOLTAGE DETECTOR EC9518C/ EC9519C PACKAGE TYPE : SOT23-3 Page 9 / 9 E-CMOS Corp.（http://www.ecmos.com.tw） Page 9 / 9 3H02N-Rev. P001