DS1094L Datasheet, PDF (1/11 Pages) Dallas Semiconductor – Multiphase Spread-Spectrum EconOscillator

Rev 1; 5/04
Multiphase Spread-Spectrum EconOscillator
General Description
The DS1094L is a silicon oscillator that generates four
multiphase, spread-spectrum, square-wave outputs.
Frequencies between 2MHz and 31.25kHz can be out-
put in either two, three, or four-phase mode. The inter-
nal master oscillator can be dithered by either 0, 2, 4,
or 8% to reduce the amount of peak spectral energy at
the fundamental and harmonic clock frequencies. This
significantly reduces the amount of electromagnetic
interference (EMI) radiation that is generated at the sys-
tem level. The DS1094L is ideally suited as a clock gen-
erator for switched-mode power supplies. The outputs
generated by the DS1094L are used by DC-DC circuit-
ry to efficiently shift voltages either up or down. The
DS1094L can be programmed using the I²C™-compati-
ble, 2-wire serial interface to select the output frequen-
cy, number of clock phases, and dither rate, or
optionally it can be shipped from the factory custom
programmed.
Applications
Switch-Mode Power Supplies
Servers
Printers
Automotive Telematics and Infotainment
Features
♦ EconOscillator™ with Two, Three, or Four Phase
Outputs
♦ Ideally Suited as the Clock Generator for Switch-
Mode Power Supplies
♦ Output Frequencies Programmable from 2MHz to
31.25kHz
♦ Dithered Output Significantly Reduces EMI
Emissions
♦ No External Timing Components Required
♦ Nonvolatile (NV) Configuration Settings
♦ User-Programmable—Factory Programmed
Options Available
♦ Operating Temperature Range: -40°C to +85°C
PART
DS1094LU
Ordering Information
TEMP RANGE
-40°C to +85°C
PIN-PACKAGE
8 µSOP
Typical Operating Circuit
Pin Configuration
V_IN
V_CC
V_OUT
R_PULLUP
V_{CC OUT1}
OUT2
OUT3
SCL _OUT4
SDA
GND
DS1094L
THREE-PHASE
EXAMPLE WITH
DITHERED CLOCKS TO
REDUCE EMI
PHASE 1
DC-DC
STEP-DOWN
CONVERTER
PHASE 2
DC-DC
STEP-DOWN
CONVERTER
PHASE 3
DC-DC
STEP-DOWN
CONVERTER
EconOscillator is a trademark of Dallas Semiconductor.
TOP VIEW
OUT1 1
OUT2 2
V_CC 3
GND 4
DS1094L
8 SCL
7 SDA
6 OUT4
5 OUT3
µSOP
I²C is a trademark of Philips Corp. Purchase of I²C compo-
nents of Maxim Integrated Products, Inc., or one of its subli-
censed Associated Companies, conveys a license under the
Philips I²C Patent Rights to use these components in an I²C
system, provided that the system conforms to the I²C Standard
Specification as defined by Philips.
______________________________________________ Maxim Integrated Products 1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.