ds1075 ETC-unknow, ds1075 Datasheet - Page 4

• Manufacturer Part Number: ds1075
• Description: Econoscillator/divider
• Manufacturer: ETC-unknow

MUX WORD Figure 2
E/I
This bit selects either the internal oscillator or the exter-
nal/crystal reference.
1=External/Crystal
Table 1
DIV1
This bit allows the master clock to be routed directly to
the output (DIV1=1). The N programmable divider is
bypassed so the programmed value of N is ignored. The
frequency of the output (f
EXTCLK depending on which reference has been
selected. If the Internal clock is selected the M prescaler
is also bypassed (the bit values of MSEL and M are
ignored) so in this case f
equals MCLK and INTCLK). If DIV1=0 the prescaler
and programmable divider function normally.
Table 2
*Assuming PDN bit = 1, otherwise internal/external selection will be controlled by the PDN/SELX pin.
DIV WORD Figure 3
DS1075
101697 4/16
(MSB)
(MSB)
0*
PDN
DIV1
BIT
BIT
0
0
1
1
1
0
0
0
0
1
1
0*
BIT*
E/I
E/I
X
X
X
0
1
0
0
0
1
0
1
OUT
OUT
0*
=INTOSC (which also
) will be INTCLK or
PDN/SELX
EN0
MSEL
BIT
PIN
0
0
1
X
X
X
0
1
0
1
1
N (9–BITS)
* These bits must be set to zero
PDN
EXTERNAL/CRYSTAL
INTERNAL
POWER–DOWN
INTERNAL
EXTERNAL/CRYSTAL
BIT
M
X
X
X
X
0
1
0=Internal Oscillator
however, if the PDN bit is set to zero the E/I bit will be
overridden by the logic level on the PDN/SELX pin.
MSEL
This bit determines whether or not the M prescaler is
bypassed.
MSEL=0 will switch in the prescaler (unless overridden
by DIV1=1), with a divide–by number determined by the
M bit.
M
This bit sets the divide–by number for the prescaler.
M=0 results in divide–by–4, M=1 results in divide–by–2.
The setting of this bit is irrelevant if either DIV1=1 or
MSEL=1.
INTERNAL OSCILLATOR DIVIDED BY 4*N
INTERNAL OSCILLATOR DIVIDED BY 2*N
INTERNAL OSCILLATOR DIVIDED BY N
EXTERNAL OSCILLATOR DIVIDED BY N
INTERNAL OSCILLATOR DIVIDED BY 1
EXTERNAL OSCILLATOR DIVIDED BY 1
M
MSEL=1 will bypass the prescaler.
OSCILLATOR
MSEL
MODE
OPERATION
DIV1
(LSB)
(LSB)
E/I