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2.

DC/DC Converter

& Voltage Regulator

Summary of Contents for SCI 7654 Series

Page 1: ...2 DC DC Converter Voltage Regulator ...

Page 2: ...current at VI 5V Three temperature gradients 0 1 0 4 and 0 6 C External shut down control 2µA maximum output current when shut down Two in series configuration doubles negative output voltage On chip RC oscillator SCI7661C0B pladtic DIP 14 pin SCI7661M0B pladtic SOP5 14 Pin SCI7661MBB pladtic SSOP2 16 pin VDD Voltage multiplier 1 Voltage multiplier 2 Oscilator Reference voltge generator Temperatur...

Page 3: ...ve charge pump connection for 2 multiplier Positive charge pump connection for 3 multiplier Negative charge pump connection for 3 multiplier or 2 multiplier output Number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Name CAP1 CAP1 CAP2 CAP2 TC1 TC2 VI VO VREG RV POFF OSC2 OSC1 VDD Temperature gradient selects Negative supply system ground 3 multiplier output Voltage regulator output Voltage regulator output a...

Page 4: ...n 1 2V and 2 2V is shown in the following figure Note that diode D1 should have a maximum forward voltage of 0 6V with 1 0mA forward current 2 RL min can be varied depending on the input voltage N 2 Boosting to a double voltage N 3 Boosting to a triple voltage OSC1 OSC2 POFF TC1 TC2 RV VO Note 3 VREG Note 3 Plastic package Items Codes Ratings Units Remarks Input supply voltage Input terminal volta...

Page 5: ...ad resistance kΩ 6 5 4 3 2 1 5 VSTA2 VSTA1 Voltage tripler Voltage doubler Symbol Parameter Conditions Input voltage Output voltage Regulator voltage Stabilization circuit operating voltage Multiplier current Stabilization current Quiescent current Clock frequency VI VO VREG VO Iopr1 Iopr2 IQ fOSC RL RRV 1MΩ VO 18V RL ROSC 1MΩ RL RRV 1MΩ VO 15V TC2 TC1 VO RL ROSC 1MΩ Rating Min 6 0 18 0 18 0 18 0 ...

Page 6: ...ure gradient POFF TC1 TC2 OSC1 and RV input leakage current Symbol RO Peff RSAT VRV CT ILKI VREG IO Conditions IO 10mA IO 5mA VREG VO VREG VO 18 to 8V VREG 8V RL Ta 25 C VO 15V VREG 8V Ta 25 C IO 0 to 10µA TC1 VDD TC2 VO RSAT VREG VO IO IO 0 to 10µA RV VDD Ta 25 C TC2 TC1 VO Ta 25 C TC2 VDD TC1 VO Ta 25 C See note Rating Min 90 0 2 3 1 7 1 1 0 25 0 5 0 7 Typ 150 95 0 0 2 5 0 8 0 1 5 1 3 0 9 0 1 0 ...

Page 7: ...17 16 15 14 13 12 11 10 9 8 40 20 0 20 40 60 80 100 Ta C f OSC KHz VI 5 0V VI 3 0V VI 2 0V Clock frequency vs External resistance Clock frequency vs Ambient temperature 150 100 50 0 7 6 5 4 3 2 1 0 VI V Iopr µA fOSC 40kHz fOSC 20kHz fOSC 10kHz Ta 25 C 0 5 10 15 0 10 20 30 40 IO mA V O V Ta 25 C VI 5 0V 2 multiplier 3 multiplier Multiplier current vs Input voltage Output voltage vs Output current ...

Page 8: ... vs Output current 100 90 80 70 60 50 40 30 20 10 0 100 90 80 70 60 50 40 30 20 10 0 0 10 20 30 40 50 IO mA I I mA Peff 3 multiplier II Ta 25 C VI 5 0V 2 multiplier Peff 3 multiplier Peff 2 multiplier II 0 5 10 15 20 25 30 IO mA 60 54 48 42 36 30 24 18 12 6 0 I I mA 100 90 80 70 60 50 40 30 20 10 0 Peff Ta 25 C VI 3 0V 3 multiplier II 3 multiplier Peff 2 multiplier Peff 2 multiplier II Multiplicat...

Page 9: ...400 300 200 100 0 7 6 5 4 3 2 1 0 VI V Rout Ω Ta 25 C IO 6mA 3 multiplier 2 multiplier Multiplication efficiency input current vs Output impedance vs Input voltage Output current 7 6 5 4 3 2 1 0 VI V 500 400 300 200 100 0 Rout Ω 3 multiplier Ta 25 C IO 10mA 2 multiplier 100 90 80 70 60 50 1 10 100 1000 fOSC kHz Peff IO 2mA IO 5mA IO 10mA IO 20mA IO 30mA Ta 25 C VI 5 0V Output impedance vs Input vo...

Page 10: ...3 0V VO 15V 7 850 7 900 7 950 8 000 0 0001 0 0010 0 0100 0 1000 Ta 25 C V REG V IO V Multiplication efficiency vs Clock frequency Output voltage vs Output current 5 850 5 900 5 950 6 000 0 0001 0 0010 0 0100 0 1000 V REG V IO V VO 9V Ta 25 C 2 850 2 900 2 950 3 000 V REG V 0 0001 0 0010 0 0100 0 1000 IO V VO 6V Ta 25 C Output voltage vs Output current Output voltage vs Output current ...

Page 11: ...e used to adjust the voltage regu lator output in applications such as power supplies for driving LCDs Notes 1 The definition of LOW for POFF differs from that for TC1 and TC2 2 The temperature gradient affects the voltage between VDD and VREG POFF 1 VDD 1 1 1 0 V1 0 0 0 TC2 See note 1 LOW VO LOW HIGH VDD HIGH LOW LOW HIGH HIGH TC1 LOW VO HIGH VDD LOW HIGH LOW HIGH LOW HIGH 0 4 0 1 0 6 0 6 Tempera...

Page 12: ... supplies a reference voltage to the voltage regulator to control the output This voltage can be switched ON and OFF VDD VREG RRV 100 kΩ to 1 MΩ RV POFF Control signal Voltage Multiplier The voltage multiplier uses the clock signal from the oscillator to double or triple the input voltage This re quires three external capacitors two charge pump ca pacitors between CAP1 and CAP1 and CAP2 and CAP2 r...

Page 13: ...Doubler To convert this curcuit to a voltage doubler remove ca pacitor C2 and short circuit CAP2 to VO VI 5 V ROSC 1 MΩ C1 10µF C2 5 V 10µF C3 10 µF VO 15 V VDD 0 V 14 13 12 11 10 9 8 1 2 3 4 5 6 7 Parallel Connection Connecting two or more chips in parallel reduces the output impedance by 1 n where n is the number of de vices used Only the single output smoothing capacitor C3 is re VDD 0 V VI 5 V...

Page 14: ...e VDD at the VREG terminal normal operation of the IC may be hampered Consequently When making a series connection insert a diode D1 between the second stage VI and VREG as shown in Fig 2 13 so that a voltage exceeding the second stage VDD or up may not be applied to the VREG terminal Positive Voltage Conversion Adding diodes converts a negative voltage to a positive one To convert the voltage tri...

Page 15: ...rates 10 and 3 8V outputs Potential levels VDD 0 V VI 5 V VO1 15 V VO2 8 2V VDD 0 V VI 5 V VO2 8 2 V VO1 15 V 10 µF 10 µF 10 µF 10 µF 10 µF 10 µF ROSC 1 MΩ D1 D2 5 V D3 1 2 3 4 5 6 7 14 13 12 11 10 9 8 Using an External Gradient The SCI7661C0B M0B offers three built in temperature gradients 0 1 0 4 and 0 6 C To set the gradient externally place a thermistor RT in series with the variable resistor ...

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