RL78/G10

2. ELECTRICAL SPECIFICATIONS

R01DS0207EJ0321 Rev.3.21

Mar 22, 2024

Page 13 of 33

2.2 Oscillator Characteristics

2.2.1 X1 oscillator characteristics

(TA =

40 to +85C, 2.0 V  VDD  5.5 V, VSS = 0 V)

Parameter

Resonator

Conditions

MIN.

TYP.

MAX.

Unit

X1 clock

oscillation

frequency

(fX)Note

Ceramic resonator/

crystal resonator

2.7 V

 VDD  5.5 V

1

20

MHz

2.0 V

 VDD < 2.7 V

1

5

MHz

Note Indicates only permissible oscillator frequency ranges. Refer to AC Characteristics for instruction execution time.

Request evaluation by the manufacturer of the oscillator circuit mounted on a board to check the oscillator

characteristics.

Caution

Since the CPU is started by the high-speed on-chip oscillator clock after a reset release, check the

X1 clock oscillation stabilization time using the oscillation stabilization time counter status register

(OSTC) by the user. Determine the oscillation stabilization time of the OSTC register and the

oscillation stabilization time select register (OSTS) after sufficiently evaluating the oscillation

stabilization time with the resonator to be used.

Remark

When using the X1 oscillator, refer to 5.4 System Clock Oscillator in the RL78/G10 User’s Manual.

2.2.2 On-chip oscillator characteristics

(TA =

40 to +85C, 2.0 V  VDD  5.5 V, VSS = 0 V)

Oscillators

Parameters

Conditions

MIN.

TYP.

MAX.

Unit

High-speed on-chip oscillator oscillation

clock frequency Notes 1, 2

fIH

1.25

20

MHz

High-speed on-chip oscillator oscillation

clock frequency accuracy

TA = -20 to +85

C

-2.0

+2.0

%

TA = -40 to -20

C

-3.0

+3.0

%

Low-speed on-chip oscillator oscillation

clock frequency

fIL

15

kHz

Low-speed on-chip oscillator oscillation

clock frequency accuracy

-15

+15

%

Notes 1.

High-speed on-chip oscillator frequency is selected by bits 0 to 2 of option byte (000C2H).

2.

This only indicates the oscillator characteristics. Refer to AC Characteristics for instruction execution time.