ICs for Timer AN6783S IC for long interval timer ■ Overview 8 2 7 3 6 4 5 0.15 0.3 4.2±0.3 0.65 • Oscillation frequency dispersion of IC itself is small (±5 %) • Oscillation frequency can be checked by 1/2 fOSC monitor terminal • Wide operating supply voltage range (3.2 V to 18 V) • Small consumption current (3 mA typ.) 1.5±0.2 0.1±0.1 ■ Features 1 5.0±0.3 1.27 0.6±0.3 0.4±0.25 Unit : mm The AN6783S is an IC designed for a long interval timer. It is oscillated by using the external resistor and capacitor, and the oscillation frequency divided by a 15stage F.F. is provided as the output. It is frequency divider type, so that a long interval timer can be constructed by using a capacitor with small capacitance. 6.5±0.3 SOP008-P-0225A ■ Applications • Timer F.F. 15 F.F. 2 F.F. 1 CR 5 6 8 7 Out VCC Mon. ■ Block Diagram OSC To each block 4 GND 3 Input circuit Reset 2 Input circuit Stop VS 1 Voltage stabilizer 1 AN6783S ICs for Timer ■ Pin Descriptions Pin No. Symbol Description 1 VS 2 Stop Oscillation stop input 3 Reset Reset input 4 GND Grounding 5 CR C and R connection 6 Out Output 7 VCC Supply voltage 8 Mon. Monitor pin Reference voltage ■ Absolute Maximum Ratings Parameter Symbol Rating Unit Supply voltage VCC 20 V Supply current ICC 7 mA PD 140 mW Topr −35 to +85 °C Tstg −55 to +125 °C Stop terminal voltage VSTOP 0 to 18 V Reset terminal voltage VRESET 0 to 18 V CR terminal voltage VCR 0 to 3 V Out terminal current IOUT −15 to +15 mA Power dissipation Operating ambient temperature Storage temperature * * Note) 1. Do not apply external currents or voltages to any pins not specifically mentioned. For circuit currents, '+' denotes current flowing into the IC, and '−' denotes current flowing out of the IC. 2. *: Except for the operating ambient temperature and storage temperature, all ratings are for Ta = 25°C. ■ Recommended Operating Range Parameter Supply voltage Symbol Range Unit VCC 3.2 to 18.0 V ■ Electrical Characteristics at Ta = 25°C Parameter 2 Symbol Conditions Min Typ Max Unit Quiescent supply current ICC VCC = 5 V 2.0 4.0 5.0 mA Internal reference voltage VS VCC = 5 V, IS = −3 mA 2.40 2.55 2.70 V High-level input current IIH VCC = 18 V, VIH = 18 V 10 µA Low-level input current IIL VCC = 18 V, VIL = 0 V −100 µA High-level out terminal voltage VOH VCC = 18 V, IOH = −10 mA 14.0 16.0 18.0 V Low-level out terminal voltage VOL VCC = 3.2 V, IOL = −10 mA 0.4 V ICs for Timer AN6783S ■ Electrical Characteristics at Ta = 25°C (continued) Parameter Symbol Conditions Min Typ Max Unit High-level Mon. terminal voltage VMH VCC = 18 V 17.8 18.0 V Low-level Mon. terminal voltage VML VCC = 3.2 V 0.4 V Oscillation frequency precision fOSC VCC = 5 V, RT = 1 kΩ, 9.0 9.5 10.0 kHz CT = 0.1 µF Oscillation frequency fluctuation with supply voltage ∆fV VCC = 5 V, 3.2 V to 18.0 V −5.0 5.0 % High-level input voltage VIH VCC = 5 V 2.0 V Low-level input voltage VIL VCC = 5 V 0.8 V • Design reference data Note) The characteristic values below are theoretical values for designing and not guaranteed. The data show the changing amount within Ta = −35°C to +85°C when the values at Ta = 25°C is taken as the reference. Parameter Symbol ∆fr Oscillation frequency- Conditions VCC = 5 V, RT = 1 kΩ, Min Typ Max Unit −5.0 5.0 % CT = 0.1 µF temperature dependency ■ Terminal Equivalent Circuits Pin No. Equivalent circuit Description I/O DC voltage 1 VS : Stabilized power supply output terminal. Reference voltage source for oscillation circuit. O 2.55 V Stop : Oscillation stop input terminal. Only the oscillation circuit stops when this terminal becomes low-level. (F.F. is not cleared) When not used, the terminal should be open or connected to VCC . I 2 VS VCC Stop 3 AN6783S ICs for Timer ■ Terminal Equivalent Circuits (continued) Pin No. Equivalent circuit 3 VS VCC Description I/O DC voltage Reset : Reset input terminal. F.F. is reset when the terminal becomes low-level and is set in the initial state. When not used, the terminal should be open or connected to VCC . The reset is applied by rising VCC from a voltage below 0.8 V (power-on reset function). I GND : Grounding terminal. 0V CR : C and R connection terminal. The oscillation period is determined by an external resistor and capacitor. When applying a pulse to this terminal from the outside, the voltage should be within the range of 0 V to 3 V. 0.7 V to 1.8 V Out : Output terminal. A frequency which is 1/32768 of the oscillation frequency is outputted. Use with an output current within ±10 mA. O High-level VCC −1.4 V VCC : Supply voltage terminal. Mon. : Oscillation frequency monitor terminal. The output is given from the first stage of F.F. and a frequency which is 1/2 of the oscillation frequency fOSC is outputted. If not used, the terminal should be open. This terminal is provided for connecting probe such as oscilloscope. Use it with an output current under 100 µA. O High-level VCC Reset 4 5 CR VS 6 VCC Out 7 8 VCC RA = 10 kΩ to 40 kΩ Mon. 4 Low-lebel < 0.4 V Low-level < 0.4 V ICs for Timer AN6783S ■ Usage Notes Pay attention to the following matters in order to prevent the destruction during the use and to increase the reliability ; 1. In the application circuit example, the calculated value by the theoretical equation for timer interval calculation and the characteristics curve vary depending on the precision of the time interval capacitor used in the actual set. Take such matter of the above into consideration. Also, the proportional constant α depends on the kinds and characteristics of the time interval resistor and time interval capacitor. Make a final confirmation with the finished products. In the case when a high precision is required, adjust the value by using a variable resistor as the time interval resistor. 2. Use a time interval resistor in the range of 1 kΩ to 1 MΩ, and a time interval capacitor in the range of 0.1 µF to 100 µF which is polyester or tantalum electrolytic capacitor with a small tanδ value. 3. Connect a capacitor (1 µF to 10 µF) to the VS terminal in order to protect the IC from an external noise and stabilize its operation. 4. If turning on power again after an extremely short-time power supply off state during the normal operation, be careful that there may be a case that the automatic reset (power-on reset) fails due to a residual potential of the external capacitance. 5. Take measures against noise in order to avoid the malfunction caused by the external noise. Pay attention to the noise from an external source especially at setting a long interval time. 6. When connecting a plunger or relay to the output circuit, connect a diode to the both ends of coil in order to protect the IC from the counter-electromotive force generted after the circuit is turned off . 7. Do not short circuit the VS terminal with VCC terminal in order to avoid malfunction. ■ Main Characteristics fOSC Rt 104 Ct = 100 µF 105 103 Ct = 0.1 µF 102 Ct = 1 µF 10 Ct = 10 µF 1 Ct = 1 µF 103 Ct = 0.1 µF 102 Ct = 100 µF 10−1 Ct = 10 µF 104 Timer interval tT (s) Oscillation frequency fOSC (Hz) tT Rt 106 10 10−2 1 1 10 102 Time decision resistance Rt (kΩ) 103 1 10 102 103 Time decision resistance Rt (kΩ) 5 AN6783S ICs for Timer ■ Main Characteristics (continued) VOH IOH VOL IOL 20 200 Ta = 25°C Ta = 25°C VCC = 5 V VCC = 18 V VCC = 18 V 160 Output voltage VOL (mV) Output voltage VOH (V) 16 12 8 4 120 80 40 VCC = 5 V VCC = 3.2 V 0 0 0 4 8 12 16 20 0 4 Output current IOH (mA) 8 1.02 Ta = 25°C 8 1.01 1.00 0.99 6 4 2 −25 0 0 25 50 75 100 0 4 8 12 16 Ambient temperature Ta (°C) Supply voltage VCC (V) ICC Ta VS Ta 4.0 20 2.62 VCR = 1.8 V 3.9 Internal reference voltage VS (V) 2.60 3.8 3.7 VCC = 18 V 3.6 3.5 VCC = 5 V 3.4 VCC = 3.2 V 3.3 3.2 2.58 2.56 VCC = 18 V 2.54 VCC = 5 V 2.52 VCC = 3.2 V 2.50 2.48 3.1 3.0 −50 20 ICC VCC VCC = 5 V R = 1 kΩ C = 0.1 µF 0.98 −50 Supply current ICC (mA) 16 10 Supply current ICC (mA) Normalized oscillation frequency fOSC (9.505 kHz) fOSC Ta −25 0 25 50 Ambient temperature Ta (°C) 6 12 Output current IOL (mA) 75 100 2.46 −50 −25 0 25 50 Ambient temperature Ta (°C) 75 100 ICs for Timer AN6783S ■ Application Circuit Example The AN6783S can be used as an integrator-type timer and as a long time timer using a stop pin. It is also usable as a ultra low frequency oscillator. 1. Ultra low frequency oscillation circuit F/F 2 F/F 1 Input circuit 1 µF to 10 µF 5 CR OSC • Output period t2(S) ≈ t0 × 32768 ≈ 31.03Rt (kΩ) · Ct (µF) Reset 3 VCC • Oscillation period t0(S) ≈ 0.947Rt (Ω) · Ct (F) Input circuit Stop 2 VS 1 Voltage stabilizer Ct GND 4 F/F 15 To Each block 6 Out 7 VCC 8 Mon. RL Rt VCR t0 Monitor t1 t1 = 2t0 Out t2 ×t ( t == 232768t ) 2 15 0 0 7 AN6783S ICs for Timer ■ Application Circuit Example (continued) 2. Timer 5 CR • Timer interval tT = 16384t0 = 16384 × 0.947Rt (Ω) · Ct (F) ≈ 15.52Rt (kΩ) · Ct (µF) OSC Input circuit Input circuit 1 µF to 10 µF RL Ct GND 4 VS 1 Voltage stabilizer F/F 1 Reset 3 To Each block F/F 2 Stop 2 F/F 15 6 Out 7 VCC 8 Mon. VCC Rt Reset VCR High t0 Reset Low Out High Low tT = 16384t0 tT Note) For AN6784 and AN6785, above descriptions can be applied to with regard to their same pin functions. 8 ICs for Timer AN6783S ■ Application Circuit Example (continued) 3. Quick check of the operation of the equipment which uses AN6783S 1) Input to pin 5 a higher frequency than the frequency with C and R, and the timer's time becomes short. Since a capacitor of big capacitance is attached at pin 5 at this moment, use a power amPulse Power plifier which has an output of a totem pole type. (If generator amplifier the output of a pulse generator is large enough, it is not necessary.) But be careful to keep an input waveform of 1.8 V or less. Oscillation waveform of pin 5 2) Place RTEST in parallel with Rt only at the test to 1.8 V lower the resistance, and an oscillation frequency 0.7 V may be high and a timer interval can be short- 1 AN6783S 5 ened. 1 RTEST Rt AN6783S 5 9