S-882Z datasheet(14/24 Pages) SII

14 / 24 page

ULTRA-LOW VOLTAGE OPERATION CHARGE PUMP IC FOR STEP-UP DC-DC CONVERTER STARTUP

S-882Z Series

Rev.1.2_00

Seiko Instruments Inc.

Precautions

• If the consumption current (ISSS) during shutdown needs to be kept at 0.8 µA or lower, set the VM pin voltage (VVM)

so that conditions (1) and (2) below are satisfied.

(1) VVM

≥ VOFF

(2) VIN

+ 1.0 V ≤ VVM ≤ 3.0 V

• If the discharge start voltage (VCPOUT1) of this IC is lower than the operating voltage of the step-up DC-DC converter

to be started, the step-up DC-DC converter may not start up. When selecting products, fully check them using an

actually mounted model. (Refer to

Selection of Product and Startup Capacitor (CCPOUT).)

• Select a capacitor with a sufficiently large capacitance for the startup capacitor. In the case of a capacitor with

insufficient capacitance, the step-up DC-DC converter may not start up. When selecting products, fully check them

using an actually mounted model. (Refer to

Selection of Product and Startup Capacitor (CCPOUT).)

• The discharge start delay time (tOUT) is longer according to conditions (1), (2), and (3) below. Also note it is further

longer when these conditions are combined.

(1) The operating input voltage (VIN) is low.

(2) The discharge start voltage (VCPOUT1) is high.

(3) The startup capacitor value (CCPOUT) is large.

• When stopping the discharge to OUT pin and recharging a startup capacitor (CCPOUT), CCPOUT is needed to be

charged until CPOUT pin voltage (VCPOUT) is lowered less than discharge stop voltage (VCPOUT2). In this case, set

the condition as follows:

Condition: OUT pin voltage (VOUT)< Discharge stop voltage (VCPOUT2)

• Note that the operation to restart a step-up DC-DC converter does not start when CPOUT pin voltage (VCPOUT)

exceeds the discharge stop voltage (VCPOUT2) even if the power-off state is released. This operation restarts if

VCPOUT is lowered than VCPOUT2 by discharge of a start-up capacitor (CCPOUT).

• When designing for mass production using an application circuit described herein, the product deviation and

temperature characteristics should be taken into consideration. SII shall not bear any responsibility for the products

on the circuits described herein.

• Do not apply an electrostatic discharge to this IC that exceeds the performance ratings of the built-in electrostatic

protection circuit.

• SII claims no responsibility for any disputes arising out of or in connection with any infringement by products

including this IC of patents owned by a third party.

S-882Z Datasheet(PDF) 14 Page - Seiko Instruments Inc