tc7662b Microchip Technology Inc., tc7662b Datasheet
tc7662b
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tc7662b Summary of contents
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... V capacitors. Operation below 10kHz (for lower supply current applications) is also possible by connecting an external capacitor from OSC to ground (with pin 1 open). The TC7662B is available in both 8-pin DIP and 8-pin IN small outline (SO) packages in commercial and extended temperature ranges. ORDERING INFORMATION Part No ...
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... In the test circuit, there is no external capacitor applied to pin 7. However, when the device is plugged into a test socket, there is usually a very small but finite stray capacitance present, of the order of 5pF. 4. The TC7662B can operate without an external diode over the full temperature and voltage range. This device will function in existing designs which incorporate an external diode with no degradation in overall circuit performance. ...
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... C . The TC7662B approaches this ideal situation 2 more closely than existing non-mechanical circuits. In the TC7662B, the four switches of Figure 2 are MOS power switches P-channel device and S 1 are N-channel devices. The main difficulty with this ap- proach is that in integrating the switches, the substrates of ...
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... TC7662B and the – terminal GND the voltage supply driving the TC7662B has a large source impedance (25-30 ohms), then a 2.2 F capaci- tor from pin 8 to ground may be required to limit the rate of rise of the input voltage to less than 2V/ sec. ...
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... Output transitions occur on the positive-going edge of the clock also possible to increase the conversion efficiency of the TC7662B at low load levels by lowering the oscillator frequency. This reduces the switching losses, and is shown Figure 8. However, lowering the oscillator frequency will 2 ...
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... Figure 8. Lowering Oscillator Frequency Positive Voltage Doubling The TC7662B may be employed to achieve positive voltage doubling using the circuit shown in Figure 9. In this application, the pump inverter switches of the TC7662B are used to charge voltage level the supply voltage and V is the forward voltage on C ...
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... CHARGE PUMP DC-TO-DC VOLTAGE CONVERTER Regulated Negative Voltage Supply In some cases, the output impedance of the TC7662B can be a problem, particularly if the load current varies substantially. The circuit of Figure 12 can be used to over- come this by controlling the input voltage, via an ICL7611 low-power CMOS op amp, in such a way as to maintain a nearly constant output voltage. Direct feedback is advisable, since the TC7662B’ ...
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... TEMPERATURE ( C) Output Source Resistance vs. Supply Voltage 100 1.5 2.5 3.5 4.5 5.5 6.5 7.5 SUPPLY VOLTAGE (V) Output Voltage vs. Output Current -10 - OUTPUT CURRENT (mA) TC7662B-8 9/11/ 101.0 100.5 100 12V IN 99.5 99 100 Output Source Resistance vs. Temperature 100 20mA 20 OUT ...
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... Plastic DIP PIN 1 .260 (6.60) .240 (6.10) .070 (1.78) .040 (1.02) .400 (10.16) .348 (8.84) .040 (1.02) .020 (0.51) .015 (0.38) .008 (0.20) .022 (0.56) .015 (0.38) 9 TC7662B Unloaded Osc Freq vs. Temperature with Boost Pin = 12V IN - TEMPERATURE ( C) .310 (7.87) .290 (7.37) 3 MIN. .400 (10.16) .310 (7.87) Dimensions: inches (mm 100 TC7662B-8 9/11/96 ...
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... TC7662B PACKAGE DIMENSIONS (Cont.) .050 (1.27) TYP. .197 (5.00) .189 (4.80) .020 (0.51) .013 (0.33) TC7662B-8 9/11/96 8-Pin SOIC .157 (3.99) .244 (6.20) .150 (3.81) .228 (5.79) .069 (1.75) .053 (1.35) 8 MAX. .010 (0.25) .050 (1.27) .004 (0.10) .016 (0.40) 10 CHARGE PUMP DC-TO-DC VOLTAGE CONVERTER .010 (0.25) .007 (0.18) Dimensions: inches (mm) © 2001 Microchip Technology Inc. DS21469A ...
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... Centro Direzionale Colleoni Palazzo Taurus Colleoni 1 20041 Agrate Brianza Milan, Italy Tel: 39-039-65791-1 Fax: 39-039-6899883 United Kingdom Arizona Microchip Technology Ltd. 505 Eskdale Road Winnersh Triangle Wokingham Berkshire, England RG41 5TU Tel: 44 118 921 5869 Fax: 44-118 921-5820 01/09/01 Printed on recycled paper. TC7662B-8 9/11/96 ...