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Seiko Epson. Seiko Epson reserves the right to make changes to this material without notice. Seiko Epson does not assume any liability of any kind arising out of any inaccuracies contained in this material or due to its application or use in any product or circuit and, further, there is no representation that this material is applicable to products requiring high level reliability, such as, medical products.
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Configuration of product number !DEVICES 76640 Packing specifications Specifications Shape (M:SOP, SSOP) Model number Model name (F : Power Supply) Product classification (S1:Semiconductors)
LCD power. The S1F76640 enables you to drive an IC (liquid crystal driver, analog IC, etc.) that would usually require another power supply in addition to the logic main power, using a single power supply. Therefore, it is suitable for supplying micro-power to compact electrical devices such as hand-held computers with low power consumption.
OSC2 Pin connected to oscillation resistor Opened for external clock operation. OSC1 Pin connected to oscillation resistor Functions as a clock input pin for external clock operation (GND) Power supply pin (Negative side, system GND) S1F76640 Technical Manual (Rev.1.5) EPSON...
5. FUNCTIONAL DESCRIPTION 5. FUNCTIONAL DESCRIPTION ! CR oscillation circuit The S1F76640 is equipped with a CR oscillation circuit as an internal oscillation circuit, connecting external resistor R for oscillation between the OSC1 and OSC2 pins (Fig.5.1). (Note 1) OSC1...
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XP = Low (GND), it is turned off. If the V output ON/OFF control is not necessary, XP is fixed to High (V ) as shown in Fig.4.5 (dashed lines). S1F76640 Technical Manual (Rev.1.5) EPSON...
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5. FUNCTIONAL DESCRIPTION % Temperature gradient selection circuit As shown in Table 5.1, the S1F76640 provides three types of temperature gradients suitable for LCD driving to output. Table 5.1 Correspondence between Temperature Gradients and V Output ON/OFF Temperature gradient CT...
No external voltage should therefore be applied to these pins. When being compelled to apply external voltage to the pins for use, it must be in the allowable range of the rated voltages above. S1F76640 Technical Manual (Rev.1.5) EPSON...
Note 4: RSAT indicates the inclination shown in Fig.7.18; V ) indicates the lower limit voltage of the V output. Note 5: The computational expression of CT is shown below: (50°C) - V (0°C) × ×100 (%/°C) 50°C - 0°C (25°C) S1F76640 Technical Manual (Rev.1.5) EPSON...
C1 to C4=10 μ F =35kHz =17.5kHz =8.75kHz Quadruple boosting Triple Ta=25 ° C Double boosting boosting C1 to C4=10 μ F [mA] Fig.7.3 Booster current consumption Fig.7.4 Output voltage (V ) - Output current ! - Input voltage S1F76640 Technical Manual (Rev.1.5) EPSON...
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) - Output current # Ta=25 ° C Ta=25 ° C =5mA =10mA Quadruple boosting Quadruple Triple Triple boosting boosting boosting Double Double boosting boosting Fig.7.7 Output impedance - Input voltage ! Fig.7.8 Output impedance - Input voltage " S1F76640 Technical Manual (Rev.1.5) EPSON...
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C1 to C4=10 μ F C1 to C4=10 μ 1000 [kHz] [mA] Fig.7.11 Boosting power conversion efficiency Fig.7.12 Boosting power conversion efficiency - Output current # - Oscillation frequency ! Input current - Output current # S1F76640 Technical Manual (Rev.1.5) EPSON...
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C1 to C4=10 μ F =20V =12V Ta=25 ° C C1 to C4=10 μ F 10.0 100.0 [k Ω ] [mA] Fig.7.15 Boosting start voltage Fig.7.16 Stabilization output saturated resistance - load resistance - Load current S1F76640 Technical Manual (Rev.1.5) EPSON...
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- Output current ! - Output current " 4.00 3.95 3.90 Ta=25 ° C 3.85 10.0 100.0 Ta [ ° C] [mA] Fig.7.19 Output voltage (V Fig.7.20 Reference voltage - Temperature - Output current # S1F76640 Technical Manual (Rev.1.5) EPSON...
Note 1: The RV pin (No.1) has high input impedance. If the wire is long, use a shield wire or the like to prevent noise. To reduce the influence of noise, it is effective to reduce the R value. (However, the R current consumption will increase.) S1F76640 Technical Manual (Rev.1.5) EPSON...
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OSC1 CAP1− 1MΩ 1MΩ OSC2 OSC2 Fig.8.5 Parallel Connection ( + 20V) 4 $ V ( + 5V) Ta=25°C (0V) [mA] Fig.8.6 Diagram of Voltage Relations Fig.8.7 Output Voltage - Output Current in Parallel Connection S1F76640 Technical Manual (Rev.1.5) EPSON...
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8. APPLIED CIRCUIT EXAMPLES (4) Serial Connection The serial connection in the S1F76640 (connecting V and V in the pre-stage to V and V in the next stage respectively) further increases output voltage. However, the serial connection raises output impedance. Fig.8.8 shows an example of serial connection for further stabilizing output by obtaining V 25V from V = 5V.
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Fig.8.9) of the IC in which the stabilizer is active. The V value changes according to temperature as follows: Δ | V CT ( V (25°C) - V ’ ) Δ T It changes at the ratio above. S1F76640 Technical Manual (Rev.1.5) EPSON...
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8. APPLIED CIRCUIT EXAMPLES (5) Negative Voltage Conversion The S1F76640 converts input voltage to negative voltage for double boosting or triple boosting through the circuit shown in Fig.8.11. (For double boosting, remove capacitor C2 and diode D3 and jumper between both ends of D3.)
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’ ( − 8.2V) 3 $ V Fig.8.15 Diagram of Voltage Relations for Negative-Voltage Conversion + Positive-Voltage Conversion Ta=25°C Io=5mA Ta=25°C '=5mA [mA] ' [mA] Fig.8.16 Output Voltage - Output Current Fig.8.17 Output Voltage - Output Current S1F76640 Technical Manual (Rev.1.5) EPSON...
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(7) Example of Changing the Temperature Gradient with an External Temperature Sensor (Thermistor) The S1F76640, which is equipped with the temperature gradient selection circuit in the stabilizer, enables you to select three types of temperature gradients (-0.30%/°C, -0.40%/°C, and -0.50%/°C) as V output.
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V CAP3+ (74HC4051) or V CAP2+ 10μF − CAP2− 10μF − CAP1+ 10μF − CAP1− OSC1 1MΩ OSC2 CTRL0 CTRL1 CTRL2 Negative power input Positive power input Fig.8.20 Electronic Volume Circuit of Voltage Stabilization Output S1F76640 Technical Manual (Rev.1.5) EPSON...
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8. APPLIED CIRCUIT EXAMPLES (9) Example of Configuration of Booster Circuits of High Magnification Using Diode Adding an external diode to the S1F76640 provides quintuple or higher boosting operation and voltage stabilization output. It is recommended to use the diode of smaller V...