Operations - Epson S1C17W14 Technical Manual

Internal gate
capacitor C
External gate
capacitor C
OSC3
G3
I/O
X'tal3/
port
Ceramic3
OSC4
External drain
Internal drain
capacitor C
D3
capacitor C
OSC3
I/O
External resistor
port
R
CR3
OSC4
For the recommended parts and the oscillation characteristics, refer to the "Basic External Connection Dia-
gram" chapter and the "Electrical Characteristics" chapter, respectively.
EXOSC clock input
EXOSC is an external clock input circuit that supports square wave and sine wave clocks. Figure 2.3.3.4 shows
the configuration of the EXOSC clock input circuit.
EXOSC has no oscillation stabilization waiting circuit included, therefore, it must be enabled when a stabilized
clock is being supplied. For the input clock characteristics, refer to "EXOSC external clock input characteris-
tics" in the "Electrical Characteristics" chapter.

2.3.4 Operations

Oscillation start time and oscillation stabilization waiting time
The oscillation start time refers to the time after the oscillator circuit is enabled until the oscillation signal is ac-
tually sent to the internal circuits. The oscillation stabilization waiting time refers to the time it takes the clock
to stabilize after the oscillation starts. To avoid malfunctions of the internal circuits due to an unstable clock
during this period, the oscillator circuit includes an oscillation stabilization waiting circuit that can disable sup-
plying the clock to the system until the designated time has elapsed. Figure 2.3.4.1 shows the relationship be-
tween the oscillation start time and the oscillation stabilization waiting time.
S1C17W14/W16 TECHNICAL MANUAL
(Rev. 1.2)
OSC3 oscillator circuit
OSC3MD[1:0]
Selector OSC3EN
Crystal/ceramic oscillator
Gain-
GI3C
controlled
inverter
Peripheral
I/O
function 4
V
SS
Feedback
resistor R
V
SS
DI3C CR oscillator
Peripheral
I/O
function 4
Internal capacitor C
Internal oscillator
OSC3FQ[2:0]
Figure 2.3.3.3 OSC3 Oscillator Circuit Configuration
EXOSC
Figure 2.3.3.4 EXOSC Clock Input Circuit
Seiko Epson Corporation
2 POWER SUPPLY, RESET, AND CLOCKS
OSC3INV[1:0]
Noise
filter
Drain resistor
R
F3 D3
Noise
filter
CR3
Clock
oscillator
EXOSC clock
input circuit
EXOSCEN
Input control
EXOSCCLK
circuit
OSC3WT[2:0]
Oscillation
stabilization OSC3CLK
waiting circuit
OSC3STAIE
Interrupt
Interrupt
control
controller
circuit
OSC3STAIF
2-9