tmp88ps34fg TOSHIBA Semiconductor CORPORATION, tmp88ps34fg Datasheet - Page 15

• Manufacturer Part Number: tmp88ps34fg
• Description: Cmos 8-bit Microcontroller
• Manufacturer: TOSHIBA Semiconductor CORPORATION

Recommended oscillating conditions
Note 1: Toshiba’s OSD circuit determines a horizontal display start position by counting clock pulses
Note 2: When using the LSI package in a strong electric field, such as near a CRT, electrically shield the
Oscillation for OSD
Item
generated in LC oscillation. For this reason, the OSD circuit may fail to detect clock pulses normally,
resulting in the horizontal start position becoming unstable, at the beginning of oscillation, if the
oscillation amplitude is low.
Changing L and C
OSD display.
If the LC oscillation frequency is the same as a high-frequency clock value, the oscillation of the
high-frequency oscillator may cause the LC oscillation frequency to fluctuate, thus making OSD
displays flicker.
When determining these parameters, please check the oscillation frequency and the stability of
oscillation on your TV sets.
Also check the determined parameters on your final products, because the optimum parameter
values may vary from one product to another.
package so that its normal operation can be maintained.
The frequency generated in LC oscillation can be obtained using the following equations.
C
f
=
1
is not fixed at a constant value. It can be changed to tune into the desired frequency.
2
π
1
LC
C ,
=
2
LC resonator
C
C
from the values recommended for a specific frequency may hamper a stable
Resonator
1
1
･
+
C
C
2
2
C
OSC1
88PS34-15
1
(V
Oscillation for OSD
SS
Frequency
Oscillation
12 MHz
16 MHz
20 MHz
24 MHz
= 0 V, V
8 MHz
L
DD
OSC2
= 4.5 V to 5.5 V, Topr = −30 to 70 °C)
C
2
L (μH)
6.8
4.7
33
15
10
Recommended parameter value
C
5 to 30
5 to 30
5 to 30
5 to 25
5 to 25
1
(pF)
TMP88PS34
2006-07-06
C
2
10
10
10
10
10
(pF)