S-8813 Datasheet, PDF (18/29 Pages) Seiko Instruments Inc – 3-CHANNEL WHITE LED DRIVER IC (CHARGE PUMP IC WITH BUILT-IN CONSTANT-CURRENT CIRCUIT)

3-CHANNEL WHITE LED DRIVER IC (CHARGE PUMP IC WITH BUILT-IN CONSTANT-CURRENT CIRCUIT)
S-8813 Series
Rev.2.1_00
 Precautions
• Regarding the wiring to the VIN pin, CPOUT pin, C+ pin, C− pin and GND pin, be careful to perform pattern
wiring so as to obtain low impedance.
• Always connect a capacitor to the CPOUT pin, C+ pin, and C− pin.
• Connect C_IN and C_OUT in the vicinity of the IC and sufficiently strengthen the wiring for GND pin and VIN pin
in order to lower the impedance of the wiring resistance, etc. High impedance may cause unstable
operation.
Moreover, in selecting C_IN and C_OUT, perform a full evaluation of the actual usage conditions.
• Connect C_PUMP in the vicinity of the IC and sufficiently strengthen the wiring for the C+ pin and C− pin in
order to lower the impedance of the wiring resistance, etc. High impedance may cause instable operation.
Moreover, in selecting C_PUMP, perform a full evaluation of the actual usage conditions.
• The oscillation pulse width may be small with a light load; however, this causes problems in the IC
operation.
• The ON/OFF pin is configured as shown in Figure 10 and is neither pulled up or down internally, so do not
use this pin in a floating state.
When not using the ON/OFF pin, connect it to the VIN pin.
Moreover, please do not impress voltage higher than V_IN+0.3 V to an ON/OFF pin. Current flows for a VIN
pin through the protection diode inside IC.
• Do not apply an electrostatic discharge to this IC that exceeds the performance ratings of the built-in
electrostatic protection circuit.
• Be careful about the usage conditions for the input/output voltages and output current to make sure that
dissipation within the IC does not exceed the allowable power dissipation of the package.
For reference, the calculation of the power consumption in this IC is shown below.
P_D= (V_IN ×2.0 −V_IOUT1,2,3) × (I_OUT1 +I_OUT2 +I_OUT3)
Reference: V_IN=4.2 V, V_IOUT1,2,3=3.6 V, I_OUT1,2,3=18 mA
P_D=(4.2 ×2.0 −3.6) ×0.054 =259 mW
• The contents of this document are subject to change in order to reflect improvements made to the IC
therein, so be sure to use the latest version of this document.
• Seiko Instruments Inc. shall not be responsible for any patent infringements caused by products using the
S-8813 Series in connection with the method in which the S-8813 Series is used in such products, the
product specifications, or the country of destination.
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Seiko Instruments Inc.