Epson S1F70000 EPSON, CR oscillator, S1F76300 Series, Internal Circuits, Basic Voltage Booster Operation

S1F76300 Series

Timing diagram Measurement circuit

VOVO

VI1

R	100 kΩ
PWCR	RST
C

PWCR

RST

tpd

PACKAGE MARKINGS

S1F76310, S1F76380 series device packages use the following markings.

7 6 3 1 Series number

First subcode character

Second subcode character

Code number

S1F76300 Series

FUNCTIONAL DESCRIPTIONS

Basic Voltage Booster Operation

Tr1 switches ON and OFF at half the frequency of the clock pulses from the built-in RC oscillator. When the transistor is ON, the circuit stores energy in L. When it is off, this energy flows through D to change C.

LD

VI1VO

Tr1	C
GND	GND

Internal CircuitsCR oscillator

The S1F76310, S1F76380 series use a built-in CR oscillator to drive the voltage booster circuit. The circuit is supplied by VI1. All circuit components are on-chip and thus the drive frequency is set internally. To ensure 50% duty, this frequency is twice that used by the voltage booster circuit.

When PS is Low, the oscillator is disabled and the chip is in standby mode.

PS

C

R

S1F70000 Series Technical Manual

EPSON 4–13