PCA84C646 Philips Semiconductors, PCA84C646 Datasheet - Page 12

• Manufacturer Part Number: PCA84C646
• Description: Microcontrollers for TV tuning control and OSD applications
• Manufacturer: Philips Semiconductors

Philips Semiconductors
1995 Jun 15
handbook, full pagewidth
Microcontrollers for TV tuning
control and OSD applications
In CASE 1 and CASE 2, a new value for VSTH, VSTL is latched into VSTREG.
In CASE 3, VSTL, together with an old value of VSTH are latched into VSTREG.
(1) t
s
f xtal
127
01
m
00
3
=
------------------------------------------ -
VSTH
Fig.8 TDAC output (not inverted) with coarse adjustment only; VSTL = 1111111; P14LVL = 0.
CASE 1
CASE 2
CASE 3
127
f
xtal
+
decimal value VSTH data latch
1
3
0
3/f xtal
VSTH
1
t
t
t
sub
sub
sub
VSTL
VSTL
(1)
Fig.7 Latching VSTH, VSTL into VSTREG.
2
VSTH
(1)
VSTH,VSTL is loaded
into VSTREG
VSTH,VSTL is loaded into VSTREG
VSTL
m
t subn
12
t
t
t
sub
sub
sub
m + 1
VSTH
(1)
m + 2
VSTH,VSTL is loaded into VSTREG
PCA84C646; PCA84C846
127
t
t
t
sub
sub
sub
Preliminary specification
0
MED180
1
MGC573