Application Circuits

The following table shows the C1, C2 and R1 values corresponding to the different crystal values. (For reference only)

Crystal or Resonator

HT46R32

HT46R34

C1, C2

R1

C1, C2

R1

8MHz Crystal

35pF

4.3k

W

TBD

TBD

8MHz Resonator

22pF

4.3k

W

TBD

TBD

4MHz Crystal & Resonator

10pF

12k

W

TBD

TBD

3.58MHz Crystal

15pF

10k

W

TBD

TBD

3.58MHz Resonator

30pF

15k

W

TBD

TBD

2MHz Crystal & Resonator

35pF

10k

W

TBD

TBD

1MHz Crystal

68pF

18k

W

TBD

TBD

480kHz Resonator

300pF

10k

W

TBD

TBD

455kHz Resonator

300pF

10k

W

TBD

TBD

429kHz Resonator

300pF

10k

W

TBD

TBD

400kHz Resonator

300pF

10k

W

TBD

TBD

The function of the resistor R1 is to ensure that the oscillator will switch off should low voltage conditions occur.

Such a low voltage, as mentioned here, is one which is less than the lowest value of the MCU operating volt-

age. Note however that if the LVR is enabled then R1 can be removed.

Note:

The resistance and capacitance for the reset circuit should be designed in such a way as to ensure that the

VDD is stable and remains within a valid operating voltage range before bringing RES to high.

²*² Make the length of the wiring, which is connected to the RES pin as short as possible, to avoid noise

interference.

HT46R32/HT46R34

Rev. 1.10

22

March 16, 2007

O S C 1

O S C 2

O S C

C i r c u i t

R E S

0 . 1 m F *

1 0 0 k W

V D D

V S S

0 . 1 m F

0 . 0 1 m F *

1 0 k W

R C S y s t e m O s c i l l a t o r

O S C 1

O S C 2

4 7 0 p F

O S C 1

O S C 2

R 1

C 1

C 2

C r y s t a l S y s t e m O s c i l l a t o r

F o r t h e v a l u e s ,

s e e t a b l e b e l o w

O S C C i r c u i t

S e e R i g h t S i d e

H T 4 6 R 3 2 / H T 4 6 R 3 4

P D 0 / P W M 0

P D 1 / P W M 1

P D 2 , P D 3

P B 0 / A N 0 ~ P B 3 / A N 3

P B 4 ~ P B 7

P A 0 ~ P A 2

P A 3 / P F D

P A 4 / T M R

P A 5 / I N T

P A 6 ~ P A 7

A P N

A P P

A P O