SG500
Low Jitter Spectrum Clock Generator for Power PC Designs
Cypress S emiconducto r Corporat i o n
525 Los Coches St. Docum ent #: 38-07015 Rev. ** 7/12/1998
Milpitas, CA 95035. Tel: 408-263-6300, Fax: 408-263-6571 Page 5 of 9
http://www.cypress.com
PPROVED PRODUC
TB4L1 BUFFER CHARACTERISTICS FOR CPU, PCI, PCIF, REF and 48M
Characteristics Symbol Min Typ Max Units Conditions
Pull-Up Current Min IOHmin -33 - - mA Vout = 1.0 V
Pull-Up Current Max IOHmax - - -33 mA Vout = 3.135 V
Pull-Down Current Min IOLmin 30 - - mA Vout = 1.95 V
Pull-Down Current Max IOLmax - - 38 mA Vout = .4 V
Rise/Fall Time Min
between 0.4V and 2.4V TRFmin 0.5 - - nS 15 pF Load
Rise/Fall Time Max
between 0.4V and 2.4V TRFmax - - 2.0 nS 30 pF Load
VDD = VDDC =CVDDP = VDDPF = VDDF = VDDR = 3.15-3.45V, TA = 0°
°°
°c TO +70°
°°
°C
Crystal and Reference Oscillator Parameters
Characteristics Symbol Min Typ Max Units Conditions
Frequency Fo12.0 14.31818 16.00 MHz
TC - - +/-100 PPM Calibration note 1
TS - - +/-100 PPM Stability (Ta-10 to +60C) Note1
Tolerance
TA - - 5 PPM Aging ( First year@ 25C) note 1
Mode OM - - - Parallel Resonant
Pin Capacitance CP 36 pF Capacitance of XIN and XOUT
pins to ground ( Each)
DC Bias Voltage VBias 0.3Vdd Vdd/2 0.7Vdd V
Start up time Ts - - 30 µS
Load Capacitance CL - 20 - pF The crystals rated load note 1
Effective Series
Resistance (ESR) R1 - - 40 Ohms
Power Dissipation DL - - 0.10 mW Note 1
Shunt Capacitance CO - - 8 pF Crystals internal package
capacitance ( total)
For maximum accuracy, the total circuit loading capacitance should be equal to CL. This loading capacitance is the
effective capacitance across the crystal pins and includes the device pin capacitance (CP) in parallel with any circuit
traces, the clock generator and any onboard discrete load capacitors.
Budgeting Calculations:
Typical trace capacitance, ( <half inch) is 4 pF, Load to the crystal is therefore = 2.0 pF
Clock generator internal pin capacitance of 36 pF, load to the crystal is therefore = 18.0 pF
The total parasitic capacitance would therefore be = 20.0 pF
Note 1. It is recommended but not mandatory that a crystal meets these specifications.