DS1089LU-22F Maxim Integrated Products, DS1089LU-22F Datasheet - Page 7

• Manufacturer Part Number: DS1089LU-22F
• Description: Timers & Support Products 3.3V Center Spread-S pectrum EconOscillat
• Manufacturer: Maxim Integrated Products

The internal master oscillator is capable of generating a
square wave with a 33.3MHz to 66.6MHz frequency
range. The master oscillator frequency (f
programmed, and is specified in the Ordering Information.
The user can program the prescaler divider to produce
an output frequency (f
P0, P1, P2, and P3 in the PRESCALER register. The
output frequency can be calculated using Equation 1.
Any value programmed greater than 2
ed as 2
where x = P3, P2, P1, P0
SPRD
V
PDN
GND
SDA
SCL
3.3V Center Spread-Spectrum EconOscillator™
CC
OE
8
Output Frequency Hz f
. See Table 1 for prescaler divider settings.
V
CC
I
INTERFACE
2
C SERIAL
EEPROM
WRITE EE
COMMAND
I
ADDRESS
BITS
2
C
OUT
Detailed Description
EEPROM
WRITE
CONTROL
) as low as 130kHz using bits
(
ADDR
PRESCALER
J3
J1
)
J2
J0
OSC
Master Oscillator
CONTROL REGISTERS
LO/
HIZ
OE
_____________________________________________________________________
=
8
X
X
MOSC
will be decod-
f
MOSC
WC
P3
H/W GATED OUTPUT
Prescaler
2
Equation 1
x
S/W GATED OUTPUT
) is factory
A2
P2
DITHER RATE
A1
P1
DITHER %
A0
P0
PROGRAMMED
Table 1. Prescaler Divider Settings
OSCILLATOR
GENERATOR
33.3MHz TO
TRIANGLE-
FACTORY-
MASTER
66.6MHz
WAVE
BITS P3, P2,
f MOD
P1, P0
0000
0001
0010
0011
0100
0101
0110
0111
1000
1111
f
MOSC
PRESCALER SETTING
f
MOSC
DIVIDE BY 1, 2, 4,
2
128
256
256
16
32
64
x
1
2
4
8
PRESCALER
8, 16, 32, 64,
128, OR 256
=
OUTPUT CONFIGURATION
OUTPUT CONTROL
DS1089L
Block Diagram
f
OSC
SYNCED
OUTPUT
BUFFER
f
f
f
f
f
f
f
MOSC
MOSC
MOSC
OUT =
f
f
f
MOSC
MOSC
MOSC
MOSC
MOSC
MOSC
f
MOSC
f
/ 128
/ 256
/ 256
/ 16
/ 32
/ 64
OSC
/ 2
/ 4
/ 8
f OUT
OUT
7