Datasheet MC12430FA, MC12430FN Datasheet (Motorola)

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Page 1



SEMICONDUCTOR TECHNICAL DATA

REV 1

 Motorola, Inc. 1997

2/97

   

The MC12430 is a general purpose synthesized clock source targeting applications that require both serial and parallel interfaces. Its internal VCO will operate over a range of frequencies from 400 to 800MHz. The differential PECL output can be configured to be the VCO frequency divided by 1, 2, 4 or 8. With the output configured to divide the VCO frequency by 2, and with a 16.000MHz external quartz crystal used to provide the reference frequency, the output frequency can be specified in 1MHz steps. The PLL loop filter is fully integrated so that no external components are required.

• 50 to 800MHz Differential PECL Outputs

• ±25ps Peak–to–Peak Output Jitter

• Fully Integrated Phase–Locked Loop

• Minimal Frequency Over–Shoot

• Synthesized Architecture

• Serial 3–Wire Interface

• Parallel Interface for Power–Up

• Quartz Crystal Interface

• 28–Lead PLCC Package

• Operates from 3.3V or 5.0V Power Supply

Functional Description

The internal oscillator uses the external quartz crystal as the basis of its frequency reference. The output of the reference oscillator is divided by 8 before being sent to the phase detector. With a 16MHz crystal, this provides a reference frequency of 2MHz. Although this data sheet illustrates functionality only for a 16MHz crystal, any crystal in the 10–20MHz range can be used.

The VCO within the PLL operates over a range of 400 to 800MHz. Its output is scaled by a divider that is configured by either the serial or parallel interfaces. The output of this loop divider is applied to the phase detector.

The phase detector and loop filter attempt to force the VCO output frequency to be M times the reference frequency by adjusting the VCO control voltage. Note that for some values of M (either too high or too low) the PLL will not achieve loop lock.

The output of the VCO is also passed through an output divider before being sent to the PECL output driver. This output divider (N divider) is configured through either the serial or the parallel interfaces, and can provide one of four division ratios (1, 2, 4 or 8). This divider extends performance of the part while providing a 50% duty cycle.

The output driver is driven differentially from the output divider, and is capable of driving a pair of transmission lines terminated in 50Ω to VCC – 2.0. The positive reference for the output driver and the internal logic is separated from the power supply for the phase–locked loop to minimize noise induced jitter.

The configuration logic has two sections: serial and parallel. The parallel interface uses the values at the M[8:0] and N[1:0] inputs to configure the internal counters. Normally, on system reset, the P_LOAD

input is held LOW until sometime after power

becomes valid. On the LOW–to–HIGH transition of P_LOAD

, the parallel inputs are captured. The parallel interface has priority over the serial interface. Internal pullup resistors are provided on the M[8:0] and N[1:0] inputs to reduce component count in the application of the chip.

The serial interface centers on a fourteen bit shift register. The shift register shifts once per rising edge of the S_CLOCK input. The serial input S_DATA must meet setup and hold timing as specified in the AC Characteristics section of this document. The configuration latches will capture the value of the shift register on the HIGH–to–LOW edge of the S_LOAD input. See the programming section for more information.

The TEST output reflects various internal node values, and is controlled by the T[2:0] bits in the serial data stream. See the programming section for more information.



HIGH FREQUENCY PLL

CLOCK GENERATOR

FN SUFFIX

28–LEAD PLCC PACKAGE

CASE 776–02

FA SUFFIX

32–LEAD TQFP PACKAGE

CASE 873A–02

Page 2

MC12430

MOTOROLA TIMING SOLUTIONS

BR1333 — Rev 6

N[1]

N[0]

M[8]

M[7]

M[6]

M[5]

M[4]XTAL1

XTAL_SEL

FREF_EXT

PLL–V

S_LOAD

S_DATA

S_CLOCK

11109

28–Lead Pinout (Top View)

P_LOAD

VCCFOUT FOUT GND VCCTEST GND

M[3]M[2]M[1]M[0]

XTAL2

N[1:0]

0 0 0 1 1 0 1 1

Output Division

2 4 8 1

Input

XTAL_SEL

FREF_EXT

Disabled

XTAL

Enabled

32–Lead Pinout

TBD

PIN DESCRIPTIONS

Pin Name Function

Inputs

XTAL1, XTAL2 These pins form an oscillator when connected to an external series–resonant crystal. S_LOAD

(Int. Pulldown)

This pin loads the configuration latches with the contents of the shift registers. The latches will be transparent when this signal is HIGH, thus the data must be stable on the HIGH–to–LOW transition of S_LOAD for proper operation.

S_DATA (Int. Pulldown)

This pin acts as the data input to the serial configuration shift registers.

S_CLOCK (Int. Pulldown)

This pin serves to clock the serial configuration shift registers. Data from S_DATA is sampled on the rising edge.

P_LOAD (Int. Pullup)

This pin loads the configuration latches with the contents of the parallel inputs .The latches will be transparent when this signal is LOW, thus the parallel data must be stable on the LOW–to–HIGH transition of P_LOAD

for proper operation.

M[8:0] (Int. Pullup)

These pins are used to configure the PLL loop divider. They are sampled on the LOW–to–HIGH transition of P_LOAD. M[8] is the MSB, M[0] is the LSB.

N[1:0] (Int. Pullup)

These pins are used to configure the output divider modulus. They are sampled on the LOW–to–HIGH transition of P_LOAD

OE (Int. Pullup)

Active HIGH Output Enable. The Enable is synchronous to eliminate possibility of runt pulse generation on the F

OUT

output.

Outputs

OUT

, F

OUT

These differential positive–referenced ECL signals (PECL) are the output of the synthesizer.

TEST The function of this output is determined by the serial configuration bits T[2:0]. The output is single–ended ECL.

Power

This is the positive supply for the internal logic and the output buffer of the chip, and is connected to +3.3V or 5.0V (VCC = PLL_VCC). Current drain through VCC ≈ 85mA.

PLL_V

This is the positive supply for the PLL, and should be as noise–free as possible for low–jitter operation. This supply is connected to +3.3V or 5.0V (VCC = PLL_VCC). Current drain through PLL_VCC ≈ 15mA.

GND These pins are the negative supply for the chip and are normally all connected to ground.

Other

FREF_EXT (Int. Pulldown)

LVCMOS/CMOS input which can be used as the PLL reference.

XTAL_SEL (Int. Pullup)

LVCMOS/CMOS input that selects between the crystal and the FREF_EXT source for the PLL reference signal. A HIGH selects the crystal input.

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MC12430

TIMING SOLUTIONS BR1333 — Rev 6

3 MOTOROLA

9–BIT SR 2–BIT SR 3–BIT SR

DIV 8

MC12430 BLOCK DIAGRAM

16MHz

S_LOAD P_LOAD

S_DATA

S_CLOCK

XTAL1

XTAL2

OSC

PHASE

DETECTOR

9–BIT DIV M

COUNTER

LATCH

VCO

DIV N

(1, 2, 4, 8)

LATCH

400–800

MHz

FOUT FOUT

+3.3 or 5.0V

25 24

CC0

LATCH

TEST

+3.3 or 5.0V

PLL_V

2MHz F

REF

CC1

+3.3 or 5.0V

M[8:0]

8:16

N[1:0]

17, 1821 22, 19

FREF_EXT

XTAL_SEL

PROGRAMMING INTERF ACE

Programming the device amounts to properly configuring the internal dividers to produce the desired frequency at the outputs. The output frequency can by represented by this formula:

FOUT = (F

XTAL

÷ 8) x M ÷ N (1)

Where F

XTAL

is the crystal frequency, M is the loop divider modulus, and N is the output divider modulus. Note that it is possible to select values of M such that the PLL is unable to achieve loop lock. To avoid this, always make sure that M is selected to be 200 ≤ M ≤ 400 for any input reference.

Assuming that a 16MHz reference frequency is used the

above equation reduces to:

FOUT = 2 x M ÷ N

Substituting the four values for N (1, 2, 4, 8) yields:

FOUT = 2M, FOUT = M, FOUT = M ÷ 2 and FOUT = M ÷ 4 for 200 < M < 400

The user can identify the proper M and N values for the desired frequency from the above equations. The four output frequency ranges established by N are 400–800MHz, 200–400MHz, 100–200MHz and 50–100MHz respectively. From these ranges the user will establish the value of N required, then the value of M can be calculated based on the appropriate equation above. For example if an output frequency of 131MHz was desired the following steps would be taken to identify the appropriate M and N values. 131MHz falls within the frequency range set by an N value of 4 so N [1:0] = 01. For N = 4 FOUT = M ÷ 2 and M = 2 x FOUT. Therefore M = 131 x 2 = 262, so M[8:0] = 100000110. Following this same procedure a user can generate any whole frequency desired between 50 and 800MHz. Note that for N > 2 fractional values of FOUT can be realized. The size of the programmable frequency steps (and thus the indicator of the fractional output frequencies acheivable) will be equal to FXTAL ÷ 8 ÷ N.

For input reference frequencies other than 16MHz the set of appropriate equations can be deduced from equation 1. For computer applications another useful frequency base would be 16.666MHz. From this reference one can generate a family of output frequencies at multiples of the 33.333MHz PCI clock. As an example to generate a 133.333MHz clock

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MC12430

MOTOROLA TIMING SOLUTIONS

BR1333 — Rev 6

from a 16.666MHz reference the following M and N values would be used:

FOUT = 16.666 ÷ 8 x M ÷ N = 2.083333 x M ÷ N

Let N = 4, M = 133.3333 ÷ 2.083333 x 4 = 256

The value for M falls within the constraints set for PLL stability, therefore N[1:0] = 01 and M[8:0} = 10000000. If the value for M fell outside of the valid range a different N value would be selected to try to move M in the appropriate direction.

The M and N counters can be loaded either through a parallel or serial interface. The parallel interface is controlled via the P_LOAD

signal such that a LOW to HIGH transition will latch the information present on the M[8:0] and N[1:0] inputs into the M and N counters. When the P_LOAD

signal is LOW the input latches will be transparent and any changes on the M[8:0] and N[1:0] inputs will affect the FOUT output pair. To use the serial port the S_CLOCK signal samples the information on the S_DA TA line and loads it into a 14 bit shift register. Note that the P_LOAD

signal must be HIGH for the serial load operation to function. The Test register is loaded with the first three bits, the N register with the next two and the M register with the final eight bits of the data streeam on the S_DATA input. For each register the most significant bit is loaded first (T2, N1 and M8). A pulse on the S_LOAD pin after the shift register is fully loaded will transfer the divide values into the counters. The HIGH to LOW transition on the S_LOAD input will latch the new divide values into the counters. NO TAG illustrates the timing diagram for both a parallel and a serial load of the MC12430 synthesizer.

M[8:0] and N[1:0] are normally specified once at power–up through the parallel interface, and then possibly again through the serial interface. This approach allows the application to come up at one frequency and then change or fine–tune the clock as the ability to control the serial interface becomes available. To minimize transients in the frequency domain, the output should be varied in the smallest step size possible. The bandwidth of the PLL is such that frequency stepping in 1MHz steps at the maximum S_CLOCK

frequency or less will cause smooth, controlled slewing of the output frequency.

The TEST output provides visibility for one of the several internal nodes as determined by the T[2:0] bits in the serial configuration stream. It is not configurable through the parallel interface. The T2, T1 and T0 control bits are preset to ‘000’ when P_LOAD

is LOW so that the PECL FOUT outputs are as jitter–free as possible. Any active signal on the TEST output pin will have detrimental affects on the jitter of the PECL output pair. In normal operations, jitter specifications are only guaranteed if the TEST output is static. The serial configuration port can be used to select one of the alternate functions for this pin.

Most of the signals available on the TEST output pin are useful only for performance verification of the MC12430 itself. However the PLL bypass mode may be of interest at the board level for functional debug. When T[2:0] is set to 110 the MC12430 is placed in PLL bypass mode. In this mode the S_CLOCK input is fed directly into the M and N dividers. The N divider drives the FOUT differential pair and the M counter drives the TEST output pin. In this mode the S_CLOCK input could be used for low speed board level functional test or debug. Bypassing the PLL and driving FOUT directly gives the user more control on the test clocks sent through the clock tree. NO TAG shows the functional setup of the PLL bypass mode. Because the S_CLOCK is a CMOS level the input frequency is limited to 250MHz or less. This means the fastest the FOUT pin can be toggled via the S_CLOCK is 250MHz as the minimum divide ratio of the N counter is 1. Note that the M counter output on the TEST output will not be a 50% duty cycle due to the way the divider is implemented.

T2 T1 T0 TEST (Pin 20)

0 0 0 0 1 1 1 1

0 0 1 1 0 0 1 1

0 1 0 1 0 1 0 1

SHIFT REGISTER OUT HIGH FREF M COUNTER OUT FOUT LOW PLL BYPASS FOUT/4

Figure 1. Timing Diagram

S_CLOCK

S_DATA

S_LOAD

M[8:0]

N[1:0]

P_LOAD

T2 T1 T0 N1 N0 M8 M7 M6 M5 M4 M3 M2 M1

M, N

First

Bit

Last

Bit

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MC12430

TIMING SOLUTIONS BR1333 — Rev 6

5 MOTOROLA

Figure 2. Serial Test Clock Block Diagram

FDIV4 MCNT

LOW FOUT MCNT

FREF

HIGH

TEST

MUX

TEST

FOUT

(VIA ENABLE GATE)

N DIVIDE

(1, 2, 4, 8)

0 1

PLL 12430

LATCH

Reset

PLOADB

M COUNTER

SLOAD

T0 T1 T2

VCO_CLK

SHIFT

REG

14–BIT

DECODE

SDATA

SCLOCK

MCNT

FREF

SEL_CLK

•

T2=T1=1, T0=0: Test Mode

•

SCLOCK is selected, MCNT is on TEST output, SCLOCK DIVIDE BY N is on FOUT pin

PLOADB acts as reset for test pin latch. When latch reset T2 data is shifted out TEST pin.

DC CHARACTERISTICS (TA = 0° to 70°C, VCC = 3.3V to 5.0V ±5%)

Symbol Characteristic Min Typ Max Unit Condition

Input HIGH Voltage 2.0 V VCC = 3.3 to 5.0V

Input LOW Voltage 0.8 V VCC = 3.3 to 5.0V

Input Current 1.0 mA

Output HIGH Voltage 2.17 2.50 V V

CC0

= 3.3V

Output LOW Voltage 1.41 1.76 V V

CC0

= 3.3V

Power Supply Current V

PLL_V

85 15

100

1. Output levels will vary 1:1 with V

CC0

variation.

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MC12430

MOTOROLA TIMING SOLUTIONS

BR1333 — Rev 6

AC CHARACTERISTICS (TA = 0° to 70°C, VCC = 3.3V to 5.0V ±5%)

Symbol Characteristic Min Max Unit Condition

MAXI

Maximum Input Frequency S_CLOCK

Xtal Oscillator

FREF_EXT

10 10

10 20

Note 3.

MHz Note 2.

MAXO

Maximum Output Frequency VCO (Internal)

FOUT

400

800 800

MHz

LOCK

Maximum PLL Lock Time 10 ms

jitter

Cycle–to–Cycle Jitter (Peak–to–Peak) Note 4. ±25

±65

ps N = 2, 4, 8; Note 5.

N = 1; Note 5.

Setup Time S_DATA to S_CLOCK

S_CLOCK to S_LOAD

M, N to P_LOAD

20 20 20

Hold Time S_DATA to S_CLOCK

M, N to P_LOAD

20 20

tpw

MIN

Minimum Pulse Width S_LOAD

P_LOAD

50 50

tr, t

Output Rise/Fall FOUT 300 800 ps 20%–80%

2. 10MHz is the maximum frequency to load the feedback devide registers. S_CLOCK can be switched at higher frequencies when used as a test clock in TEST_MODE 6.

3. Maximum frequency on FREF_EXT is a function of the internal M counter limitations. The phase detector can handle up to 100MHz on the input, but the M counter must remain in the valid range of 200 ≤ M ≤ 400. See the programming section on page 3 of this data sheet fore more details.

4. See Applications Information below for additional information.

5. 50Ω to VCC – 2.0V pull–down.

APPLICATIONS INFORMATION

Using the On–Board Crystal Oscillator

The MC12430 features a fully integrated on–board crystal oscillator to minimize system implementation costs. The oscillator is a series resonant, multivibrator type design as opposed to the more common parallel resonant oscillator design. The series resonant design provides better stability and eliminates the need for large on chip capacitors. The oscillator is totally self contained so that the only external component required is the crystal. As the oscillator is somewhat sensitive to loading on its inputs the user is advised to mount the crystal as close to the MC12430 as possible to avoid any board level parasitics. To facilitate co–location surface mount crystals are recommended, but not required.

The oscillator circuit is a series resonant circuit and thus for optimum performance a series resonant crystal should be used. Unfortunately most crystals are characterized in a parallel resonant mode. Fortunately there is no physical difference between a series resonant and a parallel resonant crystal. The difference is purely in the way the devices are characterized. As a result a parallel resonant crystal can be used with the MC12430 with only a minor error in the desired frequency. A parallel resonant mode crystal used in a series resonant circuit will exhibit a frequency of oscillation a few

hundred ppm lower than specified, a few hundred ppm translates to kHz inaccuracies. In a general computer application this level of inaccuracy is immaterial. Table 1 below specifies the performance requirements of the crystals to be used with the MC12430.

Table 1. Crystal Specifications

Parameter Value

Crystal Cut Fundamental AT Cut Resonance Series Resonance* Frequency Tolerance ±75ppm at 25°C Frequency/Temperature Stability ±150pm 0 to 70°C Operating Range 0 to 70°C Shunt Capacitance 5–7pF Equivalent Series Resistance (ESR) 50 to 80Ω Correlation Drive Level 100µW Aging 5ppm/Yr (First 3 Y ears)

* See accompanying text for series versus parallel resonant

discussion.

Page 7

MC12430

TIMING SOLUTIONS BR1333 — Rev 6

7 MOTOROLA

Power Supply Filtering

The MC12430 is a mixed analog/digital product and as such it exhibits some sensitivities that would not necessarily be seen on a fully digital product. Analog circuitry is naturally susceptible to random noise, especially if this noise is seen on the power supply pins. The MC12430 provides separate power supplies for the digital ciruitry (VCC) and the internal PLL (PLL_VCC) of the device. The purpose of this design technique is to try and isolate the high switching noise digital outputs from the relatively sensitive internal analog phase–locked loop. In a controlled environment such as an evaluation board this level of isolation is sufficient. However, in a digital system environment where it is more difficult to minimize noise on the power supplies a second level of isolation may be required. The simplest form of isolation is a power supply filter on the PLL_VCC pin for the MC12430.

NO TAG illustrates a typical power supply filter scheme. The MC12430 is most susceptible to noise with spectral content in the 1KHz to 1MHz range. Therefore the filter should be designed to target this range. The key parameter that needs to be met in the final filter design is the DC voltage drop that will be seen between the VCC supply and the PLL_VCC pin of the MC12430. From the data sheet the I

PLL_VCC

current (the current sourced through the PLL_VCC pin) is typically 15mA (20mA maximum), assuming that a minimum of 3.0V must be maintained on the PLL_VCC pin very little DC voltage drop can be tolerated when a 3.3V V

supply is used. The resistor shown in NO TAG must have a resistance of 10–15Ω to meet the voltage drop criteria. The RC filter pictured will provide a broadband filter with approximately 100:1 attenuation for noise whose spectral content is above 20KHz. As the noise frequency crosses the series resonant point of an individual capacitor it’s overall impedance begins to look inductive and thus increases with increasing frequency. The parallel capacitor combination shown ensures that a low impedance path to ground exists for frequencies well above the bandwidth of the PLL.

Figure 3. Power Supply Filter

PLL_VCC

VCC

MC12430

0.01µF

0.01

3.3V or

5.0V

RS=10–15

Ω

A higher level of attenuation can be acheived by replacing the resistor with an appropriate valued inductor. A 1000µH choke will show a significant impedance at 10KHz frequencies and above. Because of the current draw and the voltage that must be maintained on the PLL_VCC pin a low DC resistance inductor is required (less than 15Ω). Generally

the resistor/capacitor filter will be cheaper, easier to implement and provide an adequate level of supply filtering.

The MC12430 provides sub–nanosecond output edge rates and thus a good power supply bypassing scheme is a must. NO TAG shows a representaive board layout for the MC12430. There exists many different potential board layouts and the one pictured is but one. The important aspect of the layout in NO TAG is the low impedance connections between VCC and GND for the bypass capacitors. Combining good quality general purpose chip capacitors with good PCB layout techniques will produce effective capacitor resonances at frequencies adequate to supply the instantaneous switching current for the 12430 outputs. It is imperative that low inductance chip capacitors are used; it is equally important that the board layout does not introduce back all of the inductance saved by using the leadless capacitors. Thin interconnect traces between the capacitor and the power plane should be avoided and multiple large vias should be used to tie the capacitors to the buried power planes. Fat interconnect and large vias will help to minimize layout induced inductance and thus maximize the series resonant point of the bypass capacitors.

Figure 4. PCB Board Layout for MC12430

Xtal

C1 C1

R1 = 10–15

Ω

C1 = 0.01µF C2 = 22

C3 = 0.1

= V

= GND = Via

Note the dotted lines circling the crystal oscillator connection to the device. The oscillator is a series resonant circuit and the voltage amplitude across the crystal is relatively small. It is imperative that no actively switching signals cross under the crystal as crosstalk energy coupled to these lines could significantly impact the jitter of the device. Special attention should be paid to the layout of the crystal to ensure a stable, jitter free interface between the crystal and the on–board oscillator.

Although the MC12430 has several design features to minimize the susceptibility to power supply noise (isolated power and grounds and fully differential PLL) there still may be applications in which overall performance is being degraded due to system power supply noise. The power supply filter and bypass schemes discussed in this section

Page 8

MC12430

MOTOROLA TIMING SOLUTIONS

BR1333 — Rev 6

should be adequate to eliminate power supply noise related problems in most designs.

Jitter Performance of the MC12430

The MC12430 exhibits long term and cycle–to–cycle jitter which rivals that of SAW based oscillators. This jitter performance comes with the added flexibility one gets with a synthesizer over a fixed frequency oscillator.

Figure 5. RMS PLL Jitter versus VCO Frequency

400 500 600 700 800

N=2 N=4 N=8

VCO Frequency (MHz)

RMS Jitter (ps)

Figure 5 illustrates the RMS jitter performance of the MC12430 across its specified VCO frequency range. Note that the jitter is a function of both the output frequency as well as the VCO frequency, however the VCO frequency shows a much stronger dependence. The data presented has not been compensated for trigger jitter, this fact provides a measure of guardband to the reported data. In addition the data represents long term period jitter, the cycle–to–cycle jitter could not be measured to the level of accuracy required with available test equipment but certainly will be smaller than the long term period jitter.

The most commonly specified jitter parameter is cycle–to–cycle jitter. Unfortunately with today’s high performance measurement equipment there is no way to measure this parameter for jitter performance in the class demonstrated by the MC12430. As a result different methods are used which approximate cycle–to–cycle jitter. The typical method of measuring the jitter is to accumulate a large number of cycles, create a histogram of the edge placements and record peak–to–peak as well as standard deviations of the jitter. Care must be taken that the measured edge is the edge immediately following the trigger edge. The oscilloscope cannot collect adjacent pulses, rather it collects pulses from a very large sample of pulses. It is safe to assume that collecting pulse information in this mode will produce period jitter values somewhat larger than if consecutive cycles (cycle–to–cycle jitter) were measured. All of the jitter data reported on the MC12430 was collected in this manner.

Figure 6. RMS Jitter versus Output Frequency

25 50 75 100 125 150 175 200 225 250 275 300 325 350 375 400

Output Frequency (MHz)

RMS Jitter (ps)

6.25ps Reference

Figure 6 shows the jitter as a function of the output frequency. For the 12430 this information is probably of more importance. The flat line represents an RMS jitter value that corresponds to an 8 sigma ±25ps peak–to–peak long term period jitter. The graph shows that for output frequencies from 87.5 to 400MHz the jitter falls within the ±25ps peak–to–peak specification. The general trend is that as the output frequency is decreased the output edge jitter will increase.

The jitter data from Figure 5 and Figure 6 do not include the performance of the 12430 when the output is in the divide by 1 mode. In divide by one mode the output signal is a digitally doubled version of the VCO output. The period of the outputs of the digital doubler is dependent on the duty cycle of the VCO output. Since the VCO output duty cycle cannot be guaranteed to be always 50% the resulting 12430 output in divide by one mode will be bimodal at times. Since a bimodal distribution cannot be acurately represented with an rms value, peak–to–peak values of jitter for the divide by one mode are presented.

NO TAG shows the peak–to–peak jitter of the 12430 output in divide by one mode as a function of output frequency. Notice that as with the other modes the jitter improves with increasing frequency. The ± 65ps shown in the data sheet table represents a conservative value of jitter, especially for the higher vco, and thus output frequencies.

Figure 7. Peak–to–Peak Jitter versus

Output Frequency

100

120

140

400 500 600 700 800

Spec Limit N=1

Output Frequency (MHz)

Peak–to–Peak Jitter (ps)

The jitter data presented should provide users with enough information to determine the effect on their overall

Page 9

MC12430

TIMING SOLUTIONS BR1333 — Rev 6

9 MOTOROLA

timing budget. The jitter performance meets the needs of most system designs while adding the flexibility of frequency margining and field upgrades. These features are not available with a fixed frequency SAW oscillator.

Output Voltage Swing vs Frequency

In the divide by one mode the output rise and fall times will limit the peak to peak output voltage swing. For a 400MHz output the peak to peak swing of the 12430 output will be approximately 700mV. This swing will gradually degrade as the output frequency increases, at 800MHz the output swing

will be reduced to approximately 400mV. For a worst case analysis it would be safe to assume that the 12430 output will always generate at least a 400mV output swing. Note that most high speed ECL receivers require only a few hundred millivolt input swings for reliable operation. As a result the output generated by the 12430 will, under all conditions, be sufficient for clocking standard ECL devices. Note that if a larger swing is desired the 12430 could drive a single gate ECLinPS Lite amplifier like the MC100LVEL16. The LVEL16 will speed up the output edge rates and produce a full swing ECL output at 800MHz.

Page 10

MC12430

MOTOROLA TIMING SOLUTIONS

BR1333 — Rev 6

OUTLINE DIMENSIONS

FN SUFFIX

PLASTIC PLCC PACKAGE

CASE 776–02

ISSUE D

0.007 (0.180) T L

–M

SNSM

0.007 (0.180) T L

–M

SNSM

0.007 (0.180) T L

–M

SNSM

0.010 (0.250) T L

–M

SNSS

0.007 (0.180) T L

–M

SNSM

0.010 (0.250) T L

–M

SNSS

0.007 (0.180) T L

–M

SNSM

0.007 (0.180) T L

–M

SNSM

0.004 (0.100)

SEATING PLANE

–T

–

12.32

4.20

2.29

0.33

0.66

0.51

0.64

11.43

1.07

1.07 — 2

10.42

1.02

12.57

4.57

2.79

0.48

0.81 — —

11.58

1.21

1.42

0.50

10.92 —

1.27 BSC

A B C E F

H J K R U V

X Y

Z G1 K1

MIN MINMAX MAX

INCHES MILLIMETERS

DIM

NOTES:

1. DATUMS –L–, –M–, AND –N– DETERMINED WHERE TOP OF LEAD SHOULDER EXITS PLASTIC BODY AT MOLD PARTING LINE.

2. DIM G1, TRUE POSITION TO BE MEASURED AT DATUM –T–, SEATING PLANE.

3. DIM R AND U DO NOT INCLUDE MOLD FLASH. ALLOWABLE MOLD FLASH IS 0.010 (0.250) PER SIDE.

4. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982.

5. CONTROLLING DIMENSION: INCH.

6. THE PACKAGE TOP MAY BE SMALLER THAN THE PACKAGE BOTTOM BY UP TO 0.012 (0.300). DIMENSIONS R AND U ARE DETERMINED AT THE OUTERMOST EXTREMES OF THE PLASTIC BODY EXCLUSIVE OF MOLD FLASH, TIE BAR BURRS, GATE BURRS AND INTERLEAD FLASH, BUT INCLUDING ANY MISMATCH BETWEEN THE TOP AND BOTTOM OF THE PLASTIC BODY.

7. DIMENSION H DOES NOT INCLUDE DAMBAR PROTRUSION OR INTRUSION. THE DAMBAR PROTRUSION(S) SHALL NOT CAUSE THE H DIMENSION TO BE GREATER THAN 0.037 (0.940). THE DAMBAR INTRUSION(S) SHALL NOT CAUSE THE H DIMENSION TO BE SMALLER THAN 0.025 (0.635).

VIEW S

VIEW D–D

VIEW S

0.485

0.165

0.090

0.013

0.026

0.020

0.025

0.450

0.042

0.042 — 2

0.410

0.040

0.495

0.180

0.110

0.019

0.032 — —

0.456

0.048

0.056

0.020

0.430 —

0.050 BSC

–N

–

Y BRK

–M

–

–L

–

28 1

Page 11

MC12430

TIMING SOLUTIONS BR1333 — Rev 6

11 MOTOROLA

OUTLINE DIMENSIONS

FA SUFFIX

TQFP PACKAGE

CASE 873A–02

ISSUE A

DETAIL Y

BASE

METAL

SECTION AE–AE

SEATING

PLANE

0.250 (0.010)

GAUGE PLANE

DETAIL AD

NOTES:

1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982.

2. CONTROLLING DIMENSION: MILLIMETER.

3. DATUM PLANE –AB– IS LOCATED AT BOTTOM OF LEAD AND IS COINCIDENT WITH THE LEAD WHERE THE LEAD EXITS THE PLASTIC BODY AT THE BOTTOM OF THE PARTING LINE.

4. DATUMS –T–, –U–, AND –Z– TO BE DETERMINED AT DATUM PLANE –AB–.

5. DIMENSIONS S AND V TO BE DETERMINED AT SEATING PLANE –AC–.

6. DIMENSIONS A AND B DO NOT INCLUDE MOLD PROTRUSION. ALLOWABLE PROTRUSION IS

0.250 (0.010) PER SIDE. DIMENSIONS A AND B DO INCLUDE MOLD MISMATCH AND ARE DETERMINED AT DATUM PLANE –AB–.

7. DIMENSION D DOES NOT INCLUDE DAMBAR PROTRUSION. DAMBAR PROTRUSION SHALL NOT CAUSE THE D DIMENSION TO EXCEED

0.520 (0.020).

8. MINIMUM SOLDER PLATE THICKNESS SHALL BE

0.0076 (0.0003).

9. EXACT SHAPE OF EACH CORNER MAY VARY FROM DEPICTION.

DIMAMIN MAX MIN MAX

INCHES

7.000 BSC 0.276 BSC

MILLIMETERS

B 7.000 BSC 0.276 BSC C 1.400 1.600 0.055 0.063

D 0.300 0.450 0.012 0.018

E 1.350 1.450 0.053 0.057

F 0.300 0.400 0.012 0.016 G 0.800 BSC 0.031 BSC H 0.050 0.150 0.002 0.006

J 0.090 0.200 0.004 0.008 K 0.500 0.700 0.020 0.028 M 12 REF 12 REF N 0.090 0.160 0.004 0.006

P 0.400 BSC 0.016 BSC Q 1 5 1 5

R 0.150 0.250 0.006 0.010

V 9.000 BSC 0.354 BSC V1 4.500 BSC 0.177 BSC

____

DETAIL AD

B1 3.500 BSC 0.138 BSC

A1 3.500 BSC 0.138 BSC

S 9.000 BSC 0.354 BSC S1 4.500 BSC 0.177 BSC

W 0.200 REF 0.008 REF

X 1.000 REF 0.039 REF

–T–

–Z–

–U–

T–U0.20 (0.008) ZAC

T–U0.20 (0.008) ZAB

0.10 (0.004) AC

–AC–

–AB–

–T–, –U–, –Z–

T–U

0.20 (0.008) ZAC

Page 12

MC12430

MOTOROLA TIMING SOLUTIONS

BR1333 — Rev 6

Motorola reserves the right to make changes without further notice to any products herein. Motorola makes no warranty , representation or guarantee regarding the suitability of its products for any particular purpose, nor does Motorola assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation consequential or incidental damages. “T ypical” parameters which may be provided in Motorola data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including “Typicals” must be validated for each customer application by customer’s technical experts. Motorola does not convey any license under its patent rights nor the rights of others. Motorola products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the Motorola product could create a situation where personal injury or death may occur. Should Buyer purchase or use Motorola products for any such unintended or unauthorized application, Buyer shall indemnify and hold Motorola and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that Motorola was negligent regarding the design or manufacture of the part. Motorola and are registered trademarks of Motorola, Inc. Motorola, Inc. is an Equal Opportunity/Affirmative Action Employer.

How to reach us: USA/EUROPE /Locations Not Listed: Motorola Literature Distribution; JAPAN: Nippon Motorola Ltd.; Tatsumi–SPD–JLDC, 6F Seibu–Butsuryu–Center,

P.O. Box 5405; Denver, Colorado 80217. 303–675–2140 or 1–800–441–2447 3–14–2 Tatsumi Koto–Ku, T okyo 135, Japan. 81–3–3521–8315

Mfax: RMFAX0@email.sps.mot.com – TOUCHTONE 602–244–6609 ASIA/PACIFIC: Motorola Semiconductors H.K. Ltd.; 8B Tai Ping Industrial Park, INTERNET: http://www.mot.com/sps/ 51 Ting Ko k Road, Tai Po, N.T., Hong Kong. 852–26629298

MC12430/D

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