Epson S1F70000 EPSON, Powering up, S1F76300 Series, S1F76310 series, S1F76380 series, Example Circuits, Standby mode and battery backup

S1F76300 Series

VO circuit

PWCR

VI1 circuit

VI1

RST

– +

Output voltage response compensation

The S1F76380 series are provided with a response compensation input. A response compensation capacitor is connected between VCONT and VO, allowing the ripple voltage generated by the boosted output voltage to be suppressed to a minimum.

In standby mode, the booster, including the crystal os- cillator, is disabled (the switching transistor used to drive the inductor is turned OFF) and the built-in backup switch is turned ON, so that the input voltage at VI2 is output at VO. This enables the battery backup function. PS is pulled-up internally, so when standby mode is not required, the pin should be left open.

Powering up

Ensure that VO is at least the minimum operating voltage (0.9V) before switching on the booster circuit. One way to do this is to attach a battery so that VO never drops below the minimum required for backup mode. If no such external power supply is available, connect VI2 to VI1 and hold PS Low when applying power for the first time.

VI2

Battery PS

Standby mode and battery backup

The S1F76310 series are equipped with a standby mode, initiated by connecting PS to GND.

C

S1F76310M

S1F76300 Series

TYPICAL APPLICATIONS

Example Circuits

The output current, IO, and power conversion effi-	factors such as the switching frequency, type of coil,
ciency, Peff of a particular device in a series depends on	and the size and type of other external components.

S1F76310 series			S1F76380 series
	L	D	L	D
		VSW	VSW	VO
			VI1
VI1		VO
VI2	S1F76310M/C		S1F76380M/C
			GND
GND
		PWCR	C1	VCONT	C1
		R1
	PS	RST	PWCR PS RST

S1F70000 Series Technical Manual

EPSON 4–15