W183 CYPRESS | Alldatasheet
Document overview
- Manufacturer or author: Provided By ALLDATASHEET.COM(FREE DATASHEET DOWNLOAD SITE)
- PDF pages: 9
Technical content
Features
Cypress PREMIS™ family offering Generates an EMI optimized clocking signal at the out- put Selectable output frequency range Single 1.25%, 3.75% down or center spread output Integrated loop filter components Operates with a 3.3 or 5V supply Low power CMOS design Available in 14-pin SOIC (Small Outline Integrated Circuit) Key Specifications or VDD = 5V±10% Table 1. Modulation Width Selection Table 2. Frequency Range Selection PREMIS is a trademark of Cypress Semiconductor Corporation.
10 VDD
40 MHz
Document #: 38-07158 Rev. *A Page 2 of 9 Pin Definitions Pin Name Pin No. Pin Type Pin Description CLKOUT 8 O Output Modulated Frequency: Frequency modulated copy of the input clock (SSON# asserted). REFOUT 14 O Non-Modulated Output: This pin provides a copy of the reference frequency. This output will not have the Spread Spectrum feature regardless of the state of logic input SSON#. CLKIN or X1 2 I Crystal Connection or External Reference Frequency Input: This pin has dual functions. It may either be connected to an external crystal, or to an external reference clock. NC or X2 3 I Crystal Connection: Input connection for an external crystal. If using an ex- ternal reference, this pin must be left unconnected. SSON# 12 I Spread Spectrum Control (Active LOW): Asserting this signal (active LOW) turns the internal modulation waveform on. This pin has an internal pull-down resistor. SS% 6 I Modulation Width Selection: When Spread Spectrum feature is turned on, this pin is used to select the amount of variation and peak EMI reduction that is desired on the output signal. This pin has an internal pull-up resistor. OE# 13 I Output Enable (Active LOW): When this pin is held HIGH, the output buffers are placed in a high-impedance mode. This pin has an internal pull-down re- sistor. Reset 11 I Modulation Profile Restart: A rising edge on this input restarts the modulation pattern at the beginning of its defined path. This pin has an internal pull-down resistor. FS1:2 7, 1 I Frequency Selection Bits: These pins select the frequency range of opera- tion. Refer to Table 2. These pins have internal pull-up resistors. VDD 9, 10 P Power Connection: Connected to 3.3V or 5V power supply. GND 4, 5 G Ground Connection: Connect all ground pins to the common ground plane.
without resorting to costly shielding or redesign. but also in all signals which are synchronized to the clock. plified Block Diagram shows a simple implementation. reference signal is divided by Q and fed to the phase detector. modulating waveform is superimposed at the input to the VCO. cess has little impact on system performance. frequency, the modulation percentage may be varied. Figure 1. Functional Block Diagram
Document #: 38-07158 Rev. *A Page 5 of 9 Absolute Maximum Ratings[1] Stresses greater than those listed in this table may cause per- manent damage to the device. These represent a stress rating only. Operation of the device at these or any other conditions above those specified in the operating sections of this specifi- cation is not implied. Maximum conditions for extended peri- ods may affect reliability. Parameter Description Rating Unit VDD , VIN Voltage on any pin with respect to GND –0.5 to +7.0 V TSTG Storage Temperature –65 to +150 °C TA Operating Temperature 0 to +70 °C TB Ambient Temperature under Bias –55 to +125 °C PD Power Dissipation 0.5 W Parameter Description Test Condition Min. Typ. Max. Unit IDD Supply Current 18 32 mA tON Power Up Time First locked clock cycle after Power Good 5m s VIL Input Low Voltage 0.8 V VIH Input High Voltage 2.4 V VOL Output Low Voltage 0.4 V VOH Output High Voltage 2.4 V IIL Input Low Current Note 2 –50 µA IIH Input High Current Note 2 50 µA IOL Output Low Current @ 0.4V, V DD = 3.3V 15 mA IOH Output High Current @ 2.4V, V DD = 3.3V 15 mA C I Input Capacitance 7p F R P Input Pull-Up Resistor 500 k Ω ZOUT Clock Output Impedance 25 Ω Note: 1. Single Power Supply: The voltage on any input or I/O pin cannot exceed the power pin during power up. 2. Inputs FS1:2 have a pull-up resistor, Input SSON# has a pull-down resistor.
Document #: 38-07158 Rev. *A Page 6 of 9 Parameter Description Test Condition Min. Typ. Max. Unit IDD Supply Current 30 50 mA tON Power Up Time First locked clock cycle after Power Good 5m s VIL Input Low Voltage 0.15V DD V VIH Input High Voltage 0.7V DD V VOL Output Low Voltage 0.4 V VOH Output High Voltage 2.4 V IIL Input Low Current Note 3 –50 µA IIH Input High Current Note 3 50 µA IOL Output Low Current @ 0.4V, V DD = 5V 24 mA IOH Output High Current @ 2.4V, V DD = 5V 24 mA C I Input Capacitance 7p F R P Input Pull-Up Resistor 500 k Ω ZOUT Clock Output Impedance 25 Ω Symbol Parameter Test Condition Min. Typ. Max. Unit fIN Input Frequency Input Clock 28 75 MHz fOUT Output Frequency Spread Off 28 75 MHz fXOSC Crystal Oscillator Frequency 28 40 MHz tR Output Rise Time 15-pF load, 0.8V –2.4V 2 5 ns tF Output Fall Time 15-pF load, 2.4V –0.8V 2 5 ns tOD Output Duty Cycle 15-pF load 40 60 % tID Input Duty Cycle 40 60 % tJCYC Jitter, Cycle-to-Cycle 250 300 ps Harmonic Reduction f out = 40 MHz, third harmonic measured, reference board, 15-pF load 8d B Note: 3. Inputs FS2:1 have a pull-up resistor, Input SSON# has a pull-down resistor.
Document #: 38-07158 Rev. *A Page 8 of 9 © Cypress Semiconductor Corporation, 2001. The information contained herein is subject to change without notice. Cypress Semiconductor Corporation assumes no responsibility for the use of any circuitry other than circuitry embodied in a Cypress Semiconductor product. Nor does it convey or imply any license under patent or other rights. Cypress Semiconductor does not authorize its products for use as critical components in life-support systems where a malfunction or failure may reasonably be expected to result in significant injury to the user. The inclusion of Cypress Semiconductor products in life-support systems application implies that the manufacturer assumes all risk of such use and in doing so indemnifies Cypress Semiconductor against all charges. Package Diagram 14-Pin Small Outline Integrated Circuit (SOIC, 150-mil)
Document #: 38-07158 Rev. *A Page 9 of 9 Document Title: W183 Full Feature Peak Reducing EMI Solution Document Number: 38-07158 REV. ECN NO. Issue Date Orig. of Change Description of Change ** 110268 12/15/01 SZV Change from Spec number: 38-00798 to 38-07158 *A 122690 12/27/02 RBI Added power up requirements to maximum ratings information.