DatasheetsPDF.com

MB88154 Dataheets PDF



Part Number MB88154
Manufacturers Fujitsu Media Devices
Logo Fujitsu Media Devices
Description Spread Spectrum Clock Generator
Datasheet MB88154 DatasheetMB88154 Datasheet (PDF)

www.DataSheet4U.com FUJITSU SEMICONDUCTOR DATA SHEET DS04-29115-2E Spread Spectrum Clock Generator MB88154 ■ DESCRIPTION MB88154 is a clock generator for EMI (Electro Magnetic Interference) reduction. The peak of unnecessary radiation noise (EMI) can be attenuated by making the oscillation frequency slightly modulate periodically with the internal modulator. It corresponds to both of the center spread which modulates input frequency as Middle Centered and down spread which modulates so as no.

  MB88154   MB88154


Document
www.DataSheet4U.com FUJITSU SEMICONDUCTOR DATA SHEET DS04-29115-2E Spread Spectrum Clock Generator MB88154 ■ DESCRIPTION MB88154 is a clock generator for EMI (Electro Magnetic Interference) reduction. The peak of unnecessary radiation noise (EMI) can be attenuated by making the oscillation frequency slightly modulate periodically with the internal modulator. It corresponds to both of the center spread which modulates input frequency as Middle Centered and down spread which modulates so as not to exceed input frequency. ■ FEATURE • Input frequency : 16.6 MHz to 67 MHz • Output frequency: 16.6 MHz to 67 MHz (One time input frequency) • Modulation rate can select from ± 0.5%, ± 1.0%, ± 1.5% or − 1.0%, − 2.0%, − 3.0%. (For center spread / down spread.) • Equipped with crystal oscillation circuit: Range of oscillation 16.6 M MHz to 48 MHz • The external clock can be input: 16.6 MHz to 67 MHz • Modulation clock output Duty : 40% to 60% • Modulation clock Cycle-Cycle Jitter : Less than 100 ps • Low current consumption by CMOS process : 5.0 mA (24 MHz : Typ-sample, no load) • Power supply voltage : 3.3 V ± 0.3 V • Operating temperature : − 40 °C to +85 °C • Package : SOP 8-pin ■ PACKAGE 8-pin plastic SOP (FPT-8P-M02) MB88154 ■ PRODUCT LINEUP MB88154 has two kinds of input frequency, and two kinds of modulation type (center/down spread), total four lineups. Product Input/Output frequency Modulation type MB88154-102 MB88154-103 MB88154-112 MB88154-113 33 MHz to 67 MHz 16.6 MHz to 40 MHz 33 MHz to 67 MHz 16.6 MHz to 40 MHz Down Center ■ PIN ASSIGNMENT TOP VIEW CKOUT 1 VDD 2 MB88154 VSS 3 XIN 4 8 SEL1 7 REFOUT 6 SEL0 5 XOUT FPT-8P-M02 ■ PIN DESCRIPTION Pin name CKOUT VDD VSS XIN XOUT SEL0 REFOUT SEL1 I/O O ⎯ ⎯ I O I O I Pin no. 1 2 3 4 5 6 7 8 Modulated clock output pin Power supply voltage pin GND pin Crystal resonator connection pin/clock input pin Crystal resonator connection pin Modulation rate setting pin Non-modulated clock output pin Modulation rate setting pin Description 2 MB88154 ■ I/O CIRCUIT TYPE Pin Circuit type Remarks • CMOS hysteresis input SEL0 SEL1 • CMOS output • IOL = 3 mA CKOUT REFOUT Note : For XIN and XOUT pins, see “■OSCILLATION CIRCUIT” 3 MB88154 ■ HANDLING DEVICES Preventing Latchup A latchup can occur if, on this device, (a) a voltage higher than VDD or a voltage lower than VSS is applied to an input or output pin or (b) a voltage higher than the rating is applied between VDD and VSS. The latchup, if it occurs, significantly increases the power supply current and may cause thermal destruction of an element. When you use this device, be very careful not to exceed the maximum rating. Handling unused pins Do not leave an unused input pin open, since it may cause a malfunction. Handle by, using a pull-up or pull-down resistor. Unused output pin should be opened. The attention when the external clock is used Input the clock to XIN pin, and XOUT pin should be opened when you use the external clock. Please pay attention so that an overshoot and an undershoot do not occur to an input clock of XIN pin. Power supply pins Please design connecting the power supply pin of this device by as low impedance as possible from the current supply source. We recommend connecting electrolytic capacitor (about 10 µF) and the ceramic capacitor (about 0.01 µF) in parallel between VSS and VDD near the device, as a bypass capacitor. Oscillation circuit Noise near the XIN and XOUT pins may cause the device to malfunction. Design printed circuit boards so that electric wiring of XIN or XOUT pin and the resonator do not intersect other wiring. Design the printed circuit board that surrounds the XIN and XOUT pins with ground. 4 MB88154 ■ BLOCK DIAGRAM VDD SEL1 Modulation rate setting PLL block Reference clock CKOUT Clock output SEL0 XOUT Reference clock output XIN REFOUT Rf = 1 MΩ VSS 1 − M Phase compare Charge pump V/I conversion IDAC ICO Modulation Reference clock 1 − N Loop filter Clock output 1 − L Modulation logic Modulation rate setting Modulation enable setting MB88154 PLL block A glitchless IDAC (current output D/A converter) provides precise modulation, thereby dramatically reducing EMI. 5 MB88154 ■ PIN SETTING SEL 0, SEL 1 Modulation rate setting modulation rate SEL1 L L H H Notes : SEL0 L H L H MB88154-102, MB88154-103 Down spread − 1.0% − 2.0% − 3.0% No spread MB88154-112, MB88154-113 Center spread ± 0.5% ± 1.0% ± 1.5% No spread • The modulation rate can be changed at the level of the pin. Spectrum does not spread when “H” level is set to SEL0 and SEL1 pin. The clock with low jitter can be obtained. • When changing the modulation rate setting, the stabilization wait time for the modulation clock is required. The stabilization wait time for the modulation clock take the maximum value of “■ ELECTRICAL CHARACTERISTICS • AC Characteristics Lock-Up time”. • Center spread Spectrum is spread (modulated) by centering on the input frequency. Modulation width 3.0% Radiation l.


MB203LCD MB88154 NS32382-10


@ 2014 :: Datasheetspdf.com :: Semiconductors datasheet search & download site.
(Privacy Policy & Contact)