MOTOROLA MC145202DT

Order this document
by MC145202/D
SEMICONDUCTOR TECHNICAL DATA
$" &
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Includes On–Board 64/65 Prescaler
The MC145202 is a low–voltage single–package synthesizer with serial
interface capable of direct usage up to 2.0 GHz.
The counters are programmed via a synchronous serial port which is SPI
compatible. The serial port is byte-oriented to facilitate control via an MCU. Due
to the innovative BitGrabber Plus registers, the MC145202 may be cascaded
with other peripherals featuring BitGrabber Plus without requiring leading
dummy bits or address bits in the serial data stream. In addition, BitGrabber
Plus peripherals may be cascaded with existing BitGrabber peripherals.
The device features a single–ended current source/sink phase detector A
output and a double–ended phase detector B output. Both phase detectors
have linear transfer functions (no dead zones). The maximum current of the
single–ended phase detector output is determined by an external resistor tied
from the Rx pin to ground. This current can be varied via the serial port.
Slew–rate control is provided by a special driver designed for the REFout pin.
This minimizes interference caused by REFout.
This part includes a differential RF input that may be operated in a
single–ended mode. Also featured are on–board support of an external crystal
and a programmable reference output. The R, A, and N counters are fully
programmable. The C register (configuration register) allows the part to be
configured to meet various applications. A patented feature allows the C
register to shut off unused outputs, thereby minimizing system noise and
interference.
In order to have consistent lock times and prevent erroneous data from being
loaded into the counters, on–board circuitry synchronizes the update of the A
register if the A or N counters are loading. Similarly, an update of the R register
is synchronized if the R counter is loading.
The double–buffered R register allows new divide ratios to be presented to
the three counters (R, A, and N) simultaneously.
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F SUFFIX
SOG PACKAGE
CASE 751J
20
1
DT SUFFIX
TSSOP
CASE 948D
20
1
ORDERING INFORMATION
MC145202F
MC145202DT
SOG Package
TSSOP
PIN ASSIGNMENT
REFout
1
20
REFin
LD
2
19
φR
Din
3
18
CLK
φV
4
17
ENB
VPD
PDout
5
16
OUTPUT A
6
15
OUTPUT B
GND
7
14
VDD
Rx
8
13
TEST 2
TEST 1
9
12
VCC
10
11
fin
fin
Maximum Operating Frequency: 2000 MHz @ – 10 dBm
Operating Supply Current: 4 mA Nominal at 3.0 V
Operating Supply Voltage Range (VDD and VCC Pins): 2.7 to 5.5 V
Operating Supply Voltage Range of Phase Detectors (VPD Pin): 2.7 to 5.5 V
Current Source/Sink Phase Detector Output Capability: 1.7 mA @ 5.0 V
1.0 mA @ 3.0 V
Gain of Current Source/Sink Phase/Frequency Detector Controllable via
Serial Port
Operating Temperature Range: – 40 to + 85°C
R Counter Division Range: 1 and 5 to 8191
Dual–Modulus Capability Provides Total Division up to 262,143
High–Speed Serial Interface: 4 Mbps
OUTPUT A Pin, When Configured as Data Out, Permits Cascading of Devices
Two General–Purpose Digital Outputs — OUTPUT A: Totem–Pole (Push–Pull)
with Four Output Modes
OUTPUT B: Open–Drain
Patented Power–Saving Standby Feature with Orderly Recovery for
Minimizing Lock Times, Standby Current: 30 µA
Evaluation Kit Available (Part Number MC145202EVK)
See Application Note AN1253/D for Low–Pass Filter Design, and
AN1277/D for Offset Reference PLLs for Fine Resolution or Fast Hopping
BitGrabber and BitGrabber Plus are trademarks of Motorola, Inc.
REV 3
1/98
TN98012300

Motorola, Inc. 1998
MOTOROLA
MC145202
1
BLOCK DIAGRAM
DATA OUT
REFin
REFout
20
OSC OR
4–STAGE
DIVIDER
(CONFIGURABLE)
1
fR
13–STAGE R COUNTER
Din
ENB
16
LOCK DETECTOR
AND CONTROL
2
18
SHIFT
REGISTER
AND
CONTROL
LOGIC
19
8
24
BitGrabber C REGISTER
8 BITS
STANDBY
LOGIC
17
OUTPUT A
13
3
DOUBLE–BUFFERED
BitGrabber R REGISTER
16 BITS
CLK
SELECT
LOGIC
PORT
fV
6
PHASE/FREQUENCY
DETECTOR A AND CONTROL
LD
Rx
PDout
POR
3 φ
R
4 φV
PHASE/FREQUENCY
DETECTOR B AND CONTROL
2
BitGrabber A REGISTER
24 BITS
INTERNAL
CONTROL
fin
fin
6
4
12
6–STAGE
A COUNTER
12–STAGE
N COUNTER
64/65
PRESCALER
MODULUS
CONTROL
LOGIC
15
OUTPUT B
(OPEN–
DRAIN
OUTPUT)
11
10
INPUT
AMP
13
9
TEST 2
TEST 1
SUPPLY CONNECTIONS:
PIN 12 = VCC (V+ TO INPUT AMP AND 64/65 PRESCALER)
PIN 5 = VPD (V+ TO PHASE/FREQUENCY DETECTORS A AND B)
PIN 14 = VDD (V+ TO BALANCE OF CIRCUIT)
PIN 7 = GND (COMMON GROUND)
MC145202
2
MOTOROLA
MAXIMUM RATINGS* (Voltages Referenced to GND, unless otherwise stated)
Symbol
Parameter
Value
Unit
– 0.5 to + 6.0
V
DC Supply Voltage (Pin 5)
VDD – 0.5 to + 6.0
V
Vin
DC Input Voltage
– 0.5 to VDD + 0.5
V
Vout
DC Output Voltage (except OUTPUT B,
PDout, φR, φV)
– 0.5 to VDD + 0.5
V
Vout
DC Output Voltage (OUTPUT B, PDout,
φR, φV)
– 0.5 to VPD + 0.5
V
DC Input Current, per Pin (Includes
VPD)
± 10
mA
Iout
DC Output Current, per Pin
± 20
mA
IDD
DC Supply Current, VDD and GND Pins
± 30
mA
PD
Power Dissipation, per Package
300
mW
Tstg
Storage Temperature
– 65 to + 150
°C
260
°C
VCC, VDD
VPD
Iin, IPD
TL
DC Supply Voltage (Pins 12 and 14)
Lead Temperature, 1 mm from Case for
10 Seconds
This device contains protection circuitry to
guard against damage due to high static voltages or electric fields. However, precautions
must be taken to avoid applications of any voltage higher than maximum rated voltages to this
high–impedance circuit.
* Maximum Ratings are those values beyond which damage to the device may occur.
Functional operation should be restricted to the limits in the Electrical Characteristics
tables or Pin Descriptions section.
ELECTRICAL CHARACTERISTICS
(VDD = VCC = 2.7 to 5.5 V, Voltages Referenced to GND, unless otherwise stated; VPD = 2.7 to 5.5 V, TA = – 40 to 85°C)
Symbol
Parameter
Test Condition
Guaranteed
Limit
Unit
VIL
Maximum Low–Level Input Voltage
(Din, CLK, ENB)
0.3 x VDD
V
VIH
Minimum High–Level Input Voltage
(Din, CLK, ENB)
0.7 x VDD
V
VHys
Minimum Hysteresis Voltage (CLK, ENB)
VDD = 2.7 V
VDD = 4.5 V
100
250
mV
VOL
Maximum Low–Level Output Voltage
(REFout, OUTPUT A)
Iout = 20 µA, Device in Reference Mode
0.1
V
VOH
Minimum High–Level Output Voltage
(REFout, OUTPUT A)
Iout = – 20 µA, Device in Reference Mode
VDD – 0.1
V
IOL
Minimum Low–Level Output Current
(REFout, LD)
Vout = 0.3 V
0.36
mA
IOL
Minimum Low–Level Output Current
(φR, φV)
Vout = 0.3 V
0.36
mA
IOL
Minimum Low–Level Output Current
(OUTPUT A)
Vout = 0.4 V
VDD = 4.5 V
1.0
mA
IOL
Minimum Low–Level Output Current
(OUTPUT B)
Vout = 0.4 V
1.0
mA
IOH
Minimum High–Level Output Current
(REFout, LD)
Vout = VDD – 0.3 V
– 0.36
mA
IOH
Minimum High–Level Output Current
(φR, φV)
Vout = VPD – 0.3 V
– 0.36
mA
IOH
Minimum High–Level Output Current
(OUTPUT A Only)
Vout = VDD – 0.4 V
VDD = 4.5 V
– 0.6
mA
(continued)
MOTOROLA
MC145202
3
ELECTRICAL CHARACTERISTICS (continued)
Symbol
Parameter
Test Condition
Guaranteed
Limit
Unit
Iin
Maximum Input Leakage Current
(Din, CLK, ENB, REFin)
Vin = VDD or GND, Device in XTAL Mode
± 1.0
µA
Iin
Maximum Input Current
(REFin)
Vin = VDD or GND, Device in Reference Mode
± 100
µA
Maximum Output Leakage Current (PDout)
Vout = VPD or GND, Output in Floating State
± 130
nA
Vout = VPD or GND, Output in High–Impedance State
±1
µA
Maximum Standby Supply Current
(VDD + VPD Pins)
Vin = VDD or GND; Outputs Open; Device in Standby Mode,
Shut–Down Crystal Mode or REFout–Static–Low Reference
Mode; OUTPUT B Controlling VCC per Figure 21
30
µA
Maximum Phase Detector
Quiescent Current (VPD Pin)
Bit C6 = High Which Selects Phase Detector A,
PDout = Open, PDout = Static State, Bit C4 = Low Which is
not Standby, IRx = 170 µA, VPD = 5.5 V
750
µA
Bit C6 = Low Which Selects Phase Detector B, φR and
φV = Open, φR and φV = Static Low or High, Bit
C4 = Low Which is not Standby
30
IOZ
(OUTPUT B)
ISTBY
IPD
IT
Total Operating Supply Current
(VDD + VPD + VCC Pins)
fin = 2.0 GHz; REFin = 13 MHz @ 1 Vp–p;
OUTPUT A = Inactive and No Connect; VDD = VCC,
REFout, φV, φR, PDout, LD = No Connect;
Din, ENB, CLK = VDD or GND, Phase Detector B Selected
(Bit C6 = Low)
*
mA
* The nominal values are:
4 mA at VDD = 3.0 V and VPD = 3.0 V
6 mA at VDD = 5.0 V and VPD = 5.0 V
These are not guaranteed limits.
ANALOG CHARACTERISTICS — CURRENT SOURCE/SINK OUTPUT — PDout
(Iout ≤ 1 mA @ VDD = 2.7 V and Iout ≤ 1.7mA @ VDD ≥ 4.5 V, VDD = VCC = 2.7 to 5.5 V, Voltages Referenced to GND)
Parameter
Maximum Source Current Variation (Part–to–Part)
Maximum Sink–vs–Source Mismatch (Note 3)
Output Voltage Range (Note 3)
VPD
Guaranteed
Limit
Unit
2.7
± 15
%
4.5
± 15
5.5
± 15
2.7
11
4.5
11
5.5
11
Iout Variation ≤ 15%
2.7
0.5 to 2.2
Iout Variation ≤ 20%
4.5
0.5 to 3.7
Iout Variation ≤ 22%
5.5
0.5 to 4.7
Test Condition
Vout = 0.5 x VPD
Vout = 0.5 x VPD
%
V
NOTES:
1. Percentages calculated using the following formula: (Maximum Value – Minimum Value)/Maximum Value.
2. See Rx Pin Description for external resistor values.
3. This parameter is guaranteed for a given temperature within – 40 to + 85°C.
MC145202
4
MOTOROLA
AC INTERFACE CHARACTERISTICS
(VDD = VCC = 2.7 to 5.5 V, TA = – 40 to + 85°C, CL = 25 pF, Input tr = tf = 10 ns; VPD = 2.7 to 5.5 V)
Symbol
fclk
Parameter
Guaranteed
Limit
Unit
1
dc to 4.0
MHz
tPLH, tPHL
Maximum Propagation Delay, CLK to OUTPUT A (Selected as Data Out)
1, 5
100
ns
tPLH, tPHL
Maximum Propagation Delay, ENB to OUTPUT A (Selected as Port)
2, 5
150
ns
tPZL, tPLZ
Maximum Propagation Delay, ENB to OUTPUT B
2, 6
150
ns
tTLH, tTHL
Maximum Output Transition Time, OUTPUT A and OUTPUT B; tTHLonly, on OUTPUT B
1, 5, 6
50
ns
10
pF
Figure
No.
Guaranteed
Limit
Unit
Minimum Setup and Hold Times, Din vs CLK
3
50
ns
Minimum Setup, Hold and Recovery Times, ENB vs CLK
4
100
ns
tw
Minimum Pulse Width, ENB
4
*
cycles
tw
Minimum Pulse Width, CLK
1
125
ns
Maximum Input Rise and Fall Times, CLK
1
100
µs
Cin
Serial Data Clock Frequency (Note: Refer to Clock tw below)
Figure
No.
Maximum Input Capacitance – Din, ENB, CLK
TIMING REQUIREMENTS
(VDD = VCC = 2.7 to 5.5 V, TA = – 40 to + 85°C, Input tr = tf = 10 ns, unless otherwise indicated)
Symbol
tsu, th
tsu, th, trec
tr, tf
Parameter
* The minimum limit is 3 REFin cycles or 195 fin cycles, whichever is greater.
MOTOROLA
MC145202
5
SWITCHING WAVEFORMS
tf
tr
VDD
90%
CLK 50%
10%
ENB
GND
GND
tw
tPLH
tw
OUTPUT A
1/fclk
tPLH
OUTPUT A
(DATA OUT)
VDD
50%
50%
tPHL
tPLZ
90%
50%
10%
OUTPUT B
tTLH
tPHL
tPZL
50%
10%
tTHL
Figure 1.
Figure 2.
tw
tw
VDD
VALID
ENB
50%
VDD
50%
Din
GND
tsu
th
trec
VDD
th
VDD
50%
CLK
GND
tsu
GND
CLK
50%
FIRST
CLK
LAST
CLK
Figure 3.
GND
Figure 4.
+VPD
TEST POINT
TEST POINT
7.5 kΩ
DEVICE
UNDER
TEST
CL *
* Includes all probe and fixture capacitance.
Figure 5.
MC145202
6
DEVICE
UNDER
TEST
CL *
* Includes all probe and fixture capacitance.
Figure 6.
MOTOROLA
LOOP SPECIFICATIONS (VDD = VCC = 2.7 to 5.5 V unless otherwise indicated, TA = – 40 to + 85°C)
S b l
Symbol
P
Parameter
T
Test
C
Condition
di i
Guaranteed
Operating
Range
Fig.
No.
Min
Max
U i
Unit
Pin
Input Sensitivity Range, fin
500 MHz ≤ fin ≤ 2000 MHz
7
– 10
4
dBm*
fref
Input Frequency, REFin Externally Driven in
Reference Mode
Vin ≥ 400 mV p–p
8
1.5
1.5
20
30
MHz
Crystal Frequency, Crystal Mode
C1 ≤ 30 pF, C2 ≤ 30 pF, Includes Stray
Capacitance
9
2
15
MHz
Output Frequency, REFout
CL = 20 pF, Vout ≥ 1 V p–p
10, 12
dc
10
MHz
dc
2
MHz
40
18
14
120
60
50
ns
—
80
ns
—
7
pF
fXTAL
fout
f
2.7 ≤ VDD < 4.5 V
4.5 ≤ VDD ≤ 5.5 V
Operating Frequency of the Phase Detectors
Output Pulse Width (φR, φV, and LD)
tw
tTLH,
tTHL
Cin
Output Transition Times (LD, φV, and φR)
fR in Phase with fV, CL = 20 pF, φR and φV
active for LD measurement, **
VPD = 2.7 to 5.5 V
VDD = 2.7 V
VDD = 4.5 V
VDD = 5.5 V
11, 12
CL = 20 pF, VPD = 2.7 V,
VDD = VCC = 2.7 V
11, 12
Input Capacitance, REFin
* Power level at the input to the dc block.
** When PDout is active, LD minimum pulse width is approximately 5 ns.
SINE WAVE
GENERATOR
DC
BLOCK
50 Ω PAD
50 Ω
fin
TEST
POINT
OUTPUT A
fin
DEVICE
UNDER
TEST
(fV)
0.01 µF
SINE WAVE
GENERATOR
REFin OUTPUT A
50 Ω
VCC GND VDD
V+
Vin
DEVICE
UNDER
TEST
REFout
VCC GND VDD
(fR)
TEST
POINT
TEST
POINT
V+
NOTE: Alternately, the 50 Ω pad may be a T network.
Figure 7. Test Circuit
Figure 8. Test Circuit — Reference Mode
TEST
POINT
REFin OUTPUT A
C1
C2
DEVICE UNDER
TEST
1 / f REFout
(fR)
REFout
REFout
VCC GND VDD
50%
Figure 10. Switching Waveform
V+
TEST POINT
Figure 9. Test Circuit — Crystal Mode
DEVICE
UNDER
TEST
tw
OUTPUT
50%
90%
10%
tTHL
Figure 11. Switching Waveform
MOTOROLA
CL*
* Includes all probe and
fixture capacitance.
tTLH
Figure 12. Test Circuit
MC145202
7
fin (PIN 11)
SOG PACKAGE
4
4
1
3
1
3
2
2
3V
5V
Figure 13. Normalized Input Impedance at fin — Series Format (R + jx)
Table 1. Input Impedence at fin — Series Format (R + jx), VCC = 3 V
Marker
Frequency
(GHz)
Resistance
(Ω)
Reactance
(Ω)
Capacitance/
Inductance
1
0.5
11.4
– 168
1.9 pF
2
1
12.4
– 59.4
2.68 pF
3
1.5
19.8
– 34.9
3.04 pF
4
2
18.1
9.43
751 pH
Table 2. Input Impedence at fin — Series Format (R + jx), VCC = 5 V
MC145202
8
Marker
Frequency
(GHz)
Resistance
(Ω)
Reactance
(Ω)
Capacitance/
Inductance
1
0.5
11.8
–175
1.82 pF
2
1
11.5
– 64.4
2.47 pF
3
1.5
22.2
– 36.5
2.91 pF
4
2
18.4
1.14
90.4 pH
MOTOROLA
PIN DESCRIPTIONS
DIGITAL INTERFACE PINS
Din
Serial Data Input (Pin 19)
The bit stream begins with the most significant bit (MSB)
and is shifted in on the low–to–high transition of CLK. The bit
pattern is 1 byte (8 bits) long to access the C or configuration
register, 2 bytes (16 bits) to access the first buffer of the R
register, or 3 bytes (24 bits) to access the A register (see
Table 3). The values in the C, R, and A registers do not
change during shifting because the transfer of data to the
registers is controlled by ENB.
CAUTION
The value programmed for the N counter must be
greater than or equal to the value of the A counter.
The 13 least significant bits (LSBs) of the R register are
double–buffered. As indicated above, data is latched into the
first buffer on a 16–bit transfer. (The 3 MSBs are not double–
buffered and have an immediate effect after a 16–bit
transfer.) The second buffer of the R register contains the 13
bits for the R counter. This second buffer is loaded with the
contents of the first buffer when the A register is loaded (a
24–bit transfer). This allows presenting new values to the R,
A, and N counters simultaneously. If this is not required, then
the 16–bit transfer may be followed by pulsing ENB low with
no signal on the CLK pin. This is an alternate method of transferring data to the second buffer of the R register (see Figure 16).
The bit stream needs neither address nor steering bits due
to the innovative BitGrabber Plus registers. Therefore, all bits
in the stream are available to be data for the three registers.
Random access of any register is provided (i.e., the registers
may be accessed in any sequence). Data is retained in the
registers over a supply range of 2.7 to 5.5 V. The formats are
shown in Figures 14, 15, and 16.
Din typically switches near 50% of VDD to maximize noise
immunity. This input can be directly interfaced to CMOS devices with outputs guaranteed to switch near rail–to–rail.
When interfacing to NMOS or TTL devices, either a level
shifter (MC74HC14A, MC14504B) or pull–up resistor of 1 kΩ
to 10 kΩ must be used. Parameters to consider when sizing
the resistor are worst–case IOL of the driving device, maximum tolerable power consumption, and maximum data rate.
Table 3. Register Access
(MSBs are shifted in first; C0, R0, and A0 are the LSBs)
Number
of Clocks
Accessed
Register
Bit
Nomenclature
8
16
24
Other Values ≤ 32
Values > 32
C Register
R Register
A Register
Not Allowed
See Figures
22 – 25
C7, C6, C5, . . ., C0
R15, R14, R13, . . ., R0
A23, A22, A21, . . ., A0
MOTOROLA
CLK
Serial Data Clock Input (Pin 18)
Low–to–high transitions on CLK shift bits available at the
Din pin, while high–to–low transitions shift bits from OUTPUT A (when configured as Data Out, see Pin 16). The
24–1/2–stage shift register is static, allowing clock rates
down to dc in a continuous or intermittent mode.
Eight clock cycles are required to access the C register.
Sixteen clock cycles are needed for the first buffer of the R
register. Twenty–four cycles are used to access the A register. See Table 3 and Figures 14, 15, and 16. The number of
clocks required for cascaded devices is shown in Figures 23
through 25.
CLK typically switches near 50% of V DD and has a
Schmitt–triggered input buffer. Slow CLK rise and fall times
are allowed. See the last paragraph of Din for more information.
NOTE
To guarantee proper operation of the power–on
reset (POR) circuit, the CLK pin must be held at
GND (with ENB being a don’t care) or ENB must
be held at the potential of the V+ pin (with CLK being a don’t care) during power–up. Floating, toggling, or having these pins in the wrong state
during power–up does not harm the chip, but
causes two potentially undesirable effects. First,
the outputs of the device power up in an unknown
state. Second, if two devices are cascaded, the A
Registers must be written twice after power up.
After these two accesses, the two cascaded chips
perform normally.
ENB
Active Low Enable Input (Pin 17)
This pin is used to activate the serial interface to allow the
transfer of data to/from the device. When ENB is in an inactive high state, shifting is inhibited and the port is held in the
initialized state. To transfer data to the device, ENB (which
must start inactive high) is taken low, a serial transfer is
made via Din and CLK, and ENB is taken back high. The
low–to–high transition on ENB transfers data to the C or A
registers and first buffer of the R register, depending on the
data stream length per Table 3.
Transitions on ENB must not be attempted while CLK is
high. This puts the device out of synchronization with the
microcontroller. Resynchronization occurs when ENB is high
and CLK is low.
This input is also Schmitt–triggered and switches near
50% of VDD, thereby minimizing the chance of loading erroneous data into the registers. See the last paragraph of Din
for more information.
For POR information, see the note for the CLK pin.
MC145202
9
OUTPUT A
Configurable Digital Output (Pin 16)
OUTPUT A is selectable as fR, fV, Data Out, or Port. Bits
A22 and A23 in the A register control the selection; see
Figure 15.
If A23 = A22 = high, OUTPUT A is configured as fR. This
signal is the buffered output of the 13–stage R counter. The
fR signal appears as normally low and pulses high. The fR
signal can be used to verify the divide ratio of the R counter.
This ratio extends from 5 to 8191 and is determined by the
binary value loaded into bits R0–R12 in the R register. Also,
direct access to the phase detectors via the REFin pin is allowed by choosing a divide value of 1 (see Figure 16). The
maximum frequency at which the phase detectors operate is
2 MHz. Therefore, the frequency of fR should not exceed
2 MHz.
If A23 = high and A22 = low, OUTPUT A is configured as
fV. This signal is the buffered output of the 12–stage N
counter. The fV signal appears as normally low and pulses
high. The fV signal can be used to verify the operation of the
prescaler, A counter, and N counter. The divide ratio between
the fin input and the fV signal is N × 64 + A. N is the divide
ratio of the N counter and A is the divide ratio of the A
counter. These ratios are determined by bits loaded into the
A register. See Figure 15. The maximum frequency at which
the phase detectors operate is 2 MHz. Therefore, the frequency of fV should not exceed 2 MHz.
If A23 = low and A22 = high, OUTPUT A is configured as
Data Out. This signal is the serial output of the 24–1/2–stage
shift register. The bit stream is shifted out on the high–to–low
transition of the CLK input. Upon power up, OUTPUT A is
automatically configured as Data Out to facilitate cascading
devices.
If A23 = A22 = low, OUTPUT A is configured as Port. This
signal is a general–purpose digital output which may be used
as an MCU port expander. This signal is low when the Port
bit (C1) of the C register is low, and high when the Port bit is
high.
OUTPUT B
Open–Drain Digital Output (Pin 15)
This signal is a general–purpose digital output which may
be used as an MCU port expander. This signal is low when
the Out B bit (C0) of the C register is low. When the Out B bit
is high, OUTPUT B assumes the high–impedance state.
OUTPUT B may be pulled up through an external resistor or
active circuitry to any voltage less than or equal to the potential of the VPD pin. Note: the maximum voltage allowed on
the VPD pin is 5.5 V.
Upon power–up, power–on reset circuitry forces OUTPUT
B to a low level.
REFERENCE PINS
REFin and REFout
Reference Input and Reference Output (Pins 20 and 1)
Configurable pins for a Crystal or an External Reference.
This pair of pins can be configured in one of two modes: the
crystal mode or the reference mode. Bits R13, R14, and R15
in the R register control the modes as shown in Figure 16.
In crystal mode, these pins form a reference oscillator
when connected to terminals of an external parallel–reso-
MC145202
10
nant crystal. Frequency–setting capacitors of appropriate
values, as recommended by the crystal supplier, are connected from each of the two pins to ground (up to a maximum
of 30 pF each, including stray capacitance). An external resistor of 1 MΩ to 15 MΩ is connected directly across the pins
to ensure linear operation of the amplifier. The required connections for the components are shown in Figure 9.
To turn on the oscillator, bits R15, R14, and R13 must have
an octal value of one (001 in binary, respectively). This is the
active–crystal mode shown in Figure 16. In this mode, the
crystal oscillator runs and the R Counter divides the crystal
frequency, unless the part is in standby. If the part is placed in
standby via the C register, the oscillator runs, but the R
counter is stopped. However, if bits R15 to R13 have a value
of 0, the oscillator is stopped, which saves additional power.
This is the shut–down crystal mode (shown in Figure 16) and
can be engaged whether in standby or not.
In the reference mode, REFin (Pin 20) accepts a signal
from an external reference oscillator, such as a TCXO. A signal swinging from at least the VIL to VIH levels listed in the
Electrical Characteristics table may be directly coupled to the
pin. If the signal is less than this level, ac coupling must be
used as shown in Figure 8. Due to an on–board resistor
which is engaged in the reference modes, an external biasing resistor tied between REFin and REFout is not required.
With the reference mode, the REFout pin is configured as
the output of a divider. As an example, if bits R15, R14, and
R13 have an octal value of seven, the frequency at REFout is
the REFin frequency divided by 16. In addition, Figure 16
shows how to obtain ratios of eight, four, and two. A ratio of
one–to–one can be obtained with an octal value of three.
Upon power up, a ratio of eight is automatically initialized.
The maximum frequency capability of the REFout pin is listed
in the Loop Specifications table for an output swing of
1 V p–p and 20 pF loads. Therefore, for higher REFin frequencies, the one–to–one ratio may not be used for this
magnitude of signal swing and loading requirements. Likewise, for REFin frequencies above two times the highest
rated frequency, the ratio must be more than two.
The output has a special on–board driver that has slew–
rate control. This feature minimizes interference in the application.
If REFout is unused, an octal value of two should be used
for R15, R14, and R13 and the REFout pin should be floated.
A value of two allows REFin to be functional while disabling
REFout, which minimizes dynamic power consumption.
LOOP PINS
fin and fin
Frequency Inputs (Pins 11 and 10)
These pins are frequency inputs from the VCO. These pins
feed the on–board RF amplifier which drives the 64/65 prescaler. These inputs may be fed differentially. However, they
are usually used in a single–ended configuration (shown in
Figure 7). Note that fin is driven while fin must be tied to
ground via a capacitor.
Motorola does not recommend driving fin while terminating
fin because this configuration is not tested for sensitivity. The
sensitivity is dependent on the frequency as shown in the
Loop Specifications table.
MOTOROLA
PDout
Single–Ended Phase/Frequency Detector Output (Pin 6)
This is a three–state current–source/sink output for use as
a loop error signal when combined with an external low–pass
filter. The phase/frequency detector is characterized by a linear transfer function. The operation of the phase/frequency
detector is described below and is shown in Figure 17.
POL bit (C7) in the C register = low (see Figure 14)
Frequency of fV > fR or Phase of fV Leading fR: current–
sinking pulses from a floating state
Frequency of fV < fR or Phase of fV Lagging fR: current–
sourcing pulses from a floating state
Frequency and Phase of fV = fR: essentially a floating
state; voltage at pin determined by loop filter
POL bit (C7) = high
Frequency of fV > fR or Phase of fV Leading fR: current–
sourcing pulses from a floating state
Frequency of fV < fR or Phase of fV Lagging fR: current–
sinking pulses from a floating state
Frequency and Phase of fV = fR: essentially a floating
state; voltage at pin determined by loop filter
This output can be enabled, disabled, and inverted via the
C register. If desired, PDout can be forced to the high–impedance state by utilization of the disable feature in the C register (bit C6). This is a patented feature. Similarly, PDout is
forced to the high–impedance state when the device is put
into standby (STBY bit C4 = high).
The PDout circuit is powered by VPD. The phase detector
gain is controllable by bits C3, C2, and C1: gain (in amps per
radian) = PDout current divided by 2π.
φR and φV (Pins 3 and 4)
Double–Ended Phase/Frequency Detector Outputs
These outputs can be combined externally to generate a
loop error signal. Through use of a Motorola patented technique, the detector’s dead zone has been eliminated. Therefore, the phase/frequency detector is characterized by a
linear transfer function. The operation of the phase/frequency detector is described below and is shown in Figure 17.
POL bit (C7) in the C register = low (see Figure 14)
Frequency of fV > fR or Phase of fV Leading fR: φV = negative pulses, φR = essentially high
Frequency of fV < fR or Phase of fV Lagging fR: φV = essentially high, φR = negative pulses
Frequency and Phase of fV = fR: φV and φR remain essentially high, except for a small minimum time period when
both pulse low in phase
POL bit (C7) = high
Frequency of fV > fR or Phase of fV Leading fR: φR = negative pulses, φV = essentially high
Frequency of fV < fR or Phase of fV Lagging fR: φR = essentially high, φV = negative pulses
Frequency and Phase of fV = fR: φV and φR remain essentially high, except for a small minimum time period when
both pulse low in phase
These outputs can be enabled, disabled, and interchanged via C register bits C6 or C4. This is a patented fea-
MOTOROLA
ture. Note that when disabled or in standby, φR and φV are
forced to their rest condition (high state).
The φR and φV output signal swing is approximately from
GND to VPD.
LD
Lock Detector Output (Pin 2)
This output is essentially at a high level with narrow low–
going pulses when the loop is locked (fR and fV of the same
phase and frequency). The output pulses low when fV and fR
are out of phase or different frequencies. LD is the logical
ANDing of φR and φV (see Figure 17).
This output can be enabled and disabled via the C register.
This is a patented feature. Upon power up, on–chip initialization circuitry disables LD to a static low logic level to prevent
a false “lock” signal. If unused, LD should be disabled and
left open.
The LD output signal swing is approximately from GND to
VDD.
Rx
External Resistor (Pin 8)
A resistor tied between this pin and GND, in conjunction
with bits in the C register, determines the amount of current
that the PDout pin sinks and sources. When bits C2 and C3
are both set high, the maximum current is obtained at PDout;
see Tables 4 and 5 for other current values. The recommended value for Rx is 3.9 kΩ . A value of 3.9 kΩ provides
current at the PDout pin of approximately 1 mA @ VDD = 3 V
and approximately 1.7 mA @ VDD = 5 V in the 100% current
mode. Note that VDD, not VPD, is a factor in determining the
current.
When the φR and φV outputs are used, the Rx pin may be
floated.
Table 4. PDout Current*, C1 = Low with
OUTPUT A not Selected as “Port”;
Also, Default Mode When OUTPUT A
Selected as “Port”
Bit C3
Bit C2
PDout Current*
0
0
1
1
0
1
0
1
70%
80%
90%
100%
* At the time the data sheet was printed, only the 100%
current mode was guaranteed. The reduced current
modes were for experimentation only.
Table 5. PDout Current*, C1 = High with
OUTPUT A not Selected as “Port”
Bit C3
Bit C2
PDout Current*
0
0
1
1
0
1
0
1
25%
50%
75%
100%
* At the time the data sheet was printed, only the 100%
current mode was guaranteed. The reduced current
modes were for experimentation only.
MC145202
11
TEST POINT PINS
TEST 1
Modulus Control Signal (Pin 9)
This pin may be used in conjunction with the Test 2 pin for
access to the on–board 64/65 prescaler. When Test 1 is low,
the prescaler divides by 65. When high, the prescaler divides
by 64.
CAUTION
This pin is an unbuffered output and must be
floated in an actual application. This pin must be
attached to an isolated pad with no trace.
TEST 2
Prescaler Output (Pin 13)
This pin may be used to access the on–board 64/65 prescaler output.
CAUTION
This pin is an unbuffered output and must be
floated in an actual application. This pin must be
attached to an isolated pad with no trace.
POWER SUPPLY PINS
VDD
Positive Power Supply (Pin 14)
This pin supplies power to the main CMOS digital portion
of the device. Also, this pin, in conjunction with the Rx resistor, determines the internal reference current for the PDout
pin. The voltage range is + 2.7 to + 5.5 V with respect to the
GND pin.
MC145202
12
For optimum performance, VDD should be bypassed to
GND using a low–inductance capacitor mounted very close
to these pins. Lead lengths on the capacitor should be
minimized.
VCC
Positive Power Supply (Pin 12)
This pin supplies power to the RF amp and 64/65 prescaler. The voltage range is + 2.7 to + 5.5 V with respect to the
GND pin. In standby mode, the VCC pin still draws a few milliamps from the power supply. This current drain can be eliminated with the use of transistor Q1 as shown in Figure 21.
For optimum performance, VCC should be bypassed to
GND using a low–inductance capacitor mounted very close
to these pins. Lead lengths on the capacitor should be
minimized.
VPD
Positive Power Supply (Pin 5)
This pin supplies power to both phase/frequency detectors
A and B. The voltage applied on this pin may be more or less
than the potential applied to the VDD and VCC pins. The voltage range for VPD is 2.7 to 5.5 V with respect to the GND pin.
For optimum performance, VPD should be bypassed to
GND using a low–inductance capacitor mounted very close
to these pins. Lead lengths on the capacitor should be
minimized.
GND
Ground (Pin 7)
Common ground.
MOTOROLA
ENB
1
CLK
2
3
4
5
6
7
MSB
Din
C7
8
*
LSB
C6
C5
C4
C3
C2
C1
C0
* At this point, the new byte is transferred to the C register and stored. No other registers
are affected.
C7 – POL:
Selects the output polarity of the phase/frequency detectors. When set high, this bit inverts PDout
and interchanges the φR function with φV as depicted in Figure 17. Also see the phase detector output
pin descriptions for more information. This bit is cleared low at power up.
C6 – PDA/B:
Selects which phase/frequency detector is to be used. When set high, enables the output of phase/frequency detector A (PDout) and disables phase/frequency detector B by forcing φR and φV to the static
high state. When cleared low, phase/frequency detector B is enabled (φR and φV) and phase/frequency
detector A is disabled with PDout forced to the high–impedance state. This bit is cleared low at power
up.
C5 – LDE:
Enables the lock detector output when set high. When the bit is cleared low, the LD output is forced
to a static low level. This bit is cleared low at power up.
C4 – STBY:
When set, places the CMOS section of device, which is powered by the VDD and VPD pins, in the
standby mode for reduced power consumption: PDout is forced to the high–impedance state, φR and
φV are forced high, the A, N, and R counters are inhibited from counting, and the Rx current is shut
off. In standby, the state of LD is determined by bit C5. C5 low forces LD low (no change). C5 high
forces LD static high. During standby, data is retained in the A, R, and C registers. The condition
of REF/OSC circuitry is determined by the control bits in the R register: R13, R14, and R15. However,
if REFout = static low is selected, the internal feedback resistor is disconnected and the input is inhibited
when in standby; in addition, the REFin input only presents a capacitive load. NOTE: Standby does
not affect the other modes of the REF/OSC circuitry.
When C4 is reset low, the part is taken out of standby in two steps. First, the REFin (only in one
mode) resistor is reconnected, all counters are enabled, and the Rx current is enabled. Any fR and
fV signals are inhibited from toggling the phase/frequency detectors and lock detector. Second, when
the first fV pulse occurs, the R counter is jam loaded, and the phase/frequency and lock detectors
are initialized. Immediately after the jam load, the A, N, and R counters begin counting down together.
At this point, the fR and fV pulses are enabled to the phase and lock detectors. (Patented feature.)
C3, C2 – I2, I1:
Controls the PDout source/sink current per Tables 4 and 5. With both bits high, the maximum current
is available. Also, see C1 bit description.
C1 – Port:
When the OUTPUT A pin is selected as “Port” via bits A22 and A23, C1 determines the state of
OUTPUT A. When C1 is set high, OUTPUT A is forced high; C1 low forces OUTPUT A low. When
OUTPUT A is not selected as “Port,” C1 controls whether the PDout step size is 10% or 25%. (See
Tables 4 and 5.) When low, steps are 10%. When high, steps are 25%. Default is 10% steps when
OUTPUT A is selected as “Port.” The Port bit is not affected by the standby mode.
C0 – Out B:
Determines the state of OUTPUT B. When C0 is set high, OUTPUT B is high–impedance; C0 low
forces OUTPUT B low. The Out B bit is not affected by the standby mode. This bit is cleared low
at power up.
Figure 14. C Register Access and Format (8 Clock Cycles are Used)
MOTOROLA
MC145202
13
MC145202
14
CLK
ENB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
NOTE 3
D in
0
1
0
1
PORT
DATA OUT
fV
fR
A22
1
1
BOTH BITS
MUST BE
HIGH
A20
A21
A19
A18
A17
A16
F
F
F
0
0
0
0
0
0
0
0
.
.
.
F
0
0
0
0
0
0
0
0
.
.
.
A14
A13
F
E
0
1
2
3
4
5
6
7
.
.
.
A11
A10
A9
N COUNTER = ÷4095
N COUNTER = ÷4094
NOT ALLOWED
NOT ALLOWED
NOT ALLOWED
NOT ALLOWED
NOT ALLOWED
N COUNTER = ÷5
N COUNTER = ÷6
N COUNTER = ÷7
A12
HEXADECIMAL VALUE
FOR N COUNTER
A15
A8
A7
A6
0
1
2
3
.
.
.
E
F
0
1
.
.
.
F
3
3
4
4
.
.
.
F
A3
0
0
0
0
.
.
.
A4
A1
= ÷0
= ÷1
= ÷2
= ÷3
A0
NOT ALLOWED
NOT ALLOWED
NOT ALLOWED
A COUNTER = ÷ 62
A COUNTER = ÷ 63
A COUNTER
A COUNTER
A COUNTER
A COUNTER
A2
HEXADECIMAL VALUE
FOR A COUNTER
A5
LSB
NOTES:
1. A power-on initialize circuit forces the OUTPUT A function to default to Data Out.
2. The values programmed for the N counter must be greater than or equal to the values programmed for the A counter. This results in a total divide value = N x 64 + A.
3. At this point, the three new bytes are transferred to the A register. In addition, the 13 LSBs in the first buffer of the R register are transferred to the R register’s second buffer.
Thus, the R, N, and A counters can be presented new divide ratios at the same time. The first buffer of the R register is not affected. The C register is not affected.
BINARY OUTPUT A
VALUE FUNCTION
(NOTE 1)
0
0
1
1
A23
MSB
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
Figure 15. A Register Access and Format (24 Clock Cycles are Used)
MOTOROLA
ENB
CLK
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
MSB
Din
R15
16
NOTE NOTE
4
5
LSB
R14
R13
R12
R11
R10
0 CRYSTAL MODE, SHUT DOWN
1 CRYSTAL MODE, ACTIVE
2 REFERENCE MODE, REFin ENABLED and REFout
STATIC LOW
3 REFERENCE MODE, REFout = REFin (BUFFERED)
4 REFERENCE MODE, REFout = REFin/2
5 REFERENCE MODE, REFout = REFin/4
6 REFERENCE MODE, REFout = REFin/8 (NOTE 3)
7 REFERENCE MODE, REFout = REFin/16
OCTAL VALUE
R9
0
0
0
0
0
0
0
0
0
·
·
·
1
1
R8
0
0
0
0
0
0
0
0
0
·
·
·
F
F
R7
0
0
0
0
0
0
0
0
0
·
·
·
F
F
0
1
2
3
4
5
6
7
8
·
·
·
E
F
R6
R5
R4
R3
R2
R1
R0
NOT ALLOWED
R COUNTER = ÷ 1 (NOTE 6)
NOT ALLOWED
NOT ALLOWED
NOT ALLOWED
R COUNTER = ÷ 5
R COUNTER = ÷ 6
R COUNTER = ÷ 7
R COUNTER = ÷ 8
R COUNTER = ÷ 8190
R COUNTER = ÷ 8191
BINARY VALUE
HEXADECIMAL VALUE
NOTES:
1. Bits R15 through R13 control the configurable “OSC or 4–stage divider” block (see Block Diagram).
2. Bits R12 through R0 control the “13–stage R counter” block (see Block Diagram).
3. A power–on initialize circuit forces a default REFin to REFout ratio of eight.
4. At this point, bits R13, R14, and R15 are stored and sent to the “OSC or 4–Stage Divider” block in the Block Diagram. Bits R0 – R12
are loaded into the first buffer in the double–buffered section of the R register. Therefore, the R counter divide ratio is not altered yet
and retains the previous ratio loaded. The C and A registers are not affected.
5. Optional load pulse. At this point, bits R0 – R12 are transferred to the second buffer of the R register. The R counter begins dividing
by the new ratio after completing the rest of the present count cycle. CLK must be low during the ENB pulse, as shown. The C and A
registers are not affected. The first buffer of the R register is not affected. Also, see note 3 of Figure 15 for an alternate method of loading
the second buffer in the R register.
6. Allows direct access to reference input of phase/frequency detectors.
Figure 16. R Register Access and Format (16 Clock Cycles are Used)
MOTOROLA
MC145202
15
fR
REFERENCE
REFin ÷ R
VH
VL
fV
FEEDBACK
fin ÷ (N x 64 + A)
VH
VL
*
PDout
SOURCING CURRENT
FLOAT
SINKING CURRENT
φR
VH
VL
φV
VH
VL
LD
VH
VL
VH = High voltage level
VL = Low voltage level
*At this point, when both fR and fV are in phase, the output source and sink circuits are turned on for a short interval.
NOTE: The PDout either sources or sinks current during out–of–lock conditions. When locked in phase and frequency, the output is in
the floating condition and the voltage at that pin is determined by the low–pass filter capacitor. PDout, φR, and φV are shown with
the polarity bit (POL) = low; see Figure 14 for POL.
Figure 17. Phase/Frequency Detectors and Lock Detector Output Waveforms
MC145202
16
MOTOROLA
DESIGN CONSIDERATIONS
CRYSTAL OSCILLATOR CONSIDERATIONS
The following options may be considered to provide a reference frequency to Motorola’s CMOS frequency synthesizers.
Use of a Hybrid Crystal Oscillator
Commercially available temperature–compensated crystal
oscillators (TCXOs) or crystal–controlled data clock oscillators provide very stable reference frequencies. An oscillator
capable of CMOS logic levels at the output may be direct or
dc coupled to REFin. If the oscillator does not have CMOS
logic levels on the outputs, capacitive or ac coupling to REFin
may be used (see Figure 8).
For additional information about TCXOs and data clock
oscillators, please consult the latest version of the eem Electronic Engineers Master Catalog, the Gold Book, or similar
publications.
by the crystal manufacturer represents the maximum stress
that the crystal can withstand without damage or excessive
shift in operating frequency. R1 in Figure 18 limits the drive
level. The use of R1 is not necessary in most cases.
To verify that the maximum dc supply voltage does not
cause the crystal to be overdriven, monitor the output
frequency (fR) at OUTPUT A as a function of supply voltage.
(REFout is not used because loading impacts the oscillator.)
The frequency should increase very slightly as the dc supply
voltage is increased. An overdriven crystal decreases in frequency or becomes unstable with an increase in supply voltage. The operating supply voltage must be reduced or R1
must be increased in value if the overdriven condition exists.
The user should note that the oscillator start–up time is proportional to the value of R1.
Through the process of supplying crystals for use with
CMOS inverters, many crystal manufacturers have developed expertise in CMOS oscillator design with crystals. Discussions with such manufacturers can prove very helpful
(see Table 6).
Design an Off–Chip Reference
FREQUENCY SYNTHESIZER
The user may design an off–chip crystal oscillator using
discrete transistors or ICs specifically developed for crystal
oscillator applications, such as the MC12061 MECL device.
The reference signal from the MECL device is ac coupled to
REFin (see Figure 8). For large amplitude signals (standard
CMOS logic levels), dc coupling may be used.
REFin
R1*
Use of the On–Chip Oscillator Circuitry
The on–chip amplifier (a digital inverter) along with an appropriate crystal may be used to provide a reference source
frequency. A fundamental mode crystal, parallel resonant at
the desired operating frequency, should be connected as
shown in Figure 18.
The crystal should be specified for a loading capacitance
(CL ) which does not exceed approximately 20 pF when used
at the highest operating frequencies listed in the Loop Specifications table. Assuming R1 = 0 Ω, the shunt load capacitance (CL ) presented across the crystal can be estimated to
be:
CL = CinCout + Ca + Cstray + C1 • C2
C1 + C2
Cin + Cout
C1
MOTOROLA
C2
* May be needed in certain cases. See text.
Figure 18. Pierce Crystal Oscillator Circuit
Ca
REFin
REFout
Cin
Cout
Cstray
where
Cin = 5 pF (see Figure 19)
Cout = 6 pF (see Figure 19)
Ca = 1 pF (see Figure 19)
C1 and C2 = external capacitors (see Figure 18)
Cstray = the total equivalent external circuit stray
capacitance appearing across the crystal
terminals
The oscillator can be “trimmed” on–frequency by making a
portion or all of C1 variable. The crystal and associated components must be located as close as possible to the REFin
and REFout pins to minimize distortion, stray capacitance,
stray inductance, and startup stabilization time. Circuit stray
capacitance can also be handled by adding the appropriate
stray value to the values for Cin and Cout. For this approach,
the term Cstray becomes 0 in the above expression for CL.
Power is dissipated in the effective series resistance of the
crystal, Re, in Figure 20. The maximum drive level specified
REFout
Rf
Figure 19. Parasitic Capacitances of the
Amplifier and Cstray
RS
1
2
CS
LS
1
2
CO
1
Re
Xe
2
NOTE: Values are supplied by crystal manufacturer
(parallel resonant crystal).
Figure 20. Equivalent Crystal Networks
MC145202
17
RECOMMENDED READING
Technical Note TN–24, Statek Corp.
Technical Note TN–7, Statek Corp.
E. Hafner, “The Piezoelectric Crystal Unit–Definitions and
Method of Measurement”, Proc. IEEE, Vol. 57, No. 2, Feb.
1969.
D. Kemper, L. Rosine, “Quartz Crystals for Frequency
Control”, Electro–Technology, June 1969.
P. J. Ottowitz, “A Guide to Crystal Selection”, Electronic
Design, May 1966.
D. Babin, “Designing Crystal Oscillators”, Machine Design,
March 7, 1985.
D. Babin, “Guidelines for Crystal Oscillator Design”,
Machine Design, April 25, 1985.
Table 6. Partial List of Crystal Manufacturers
Motorola — Internet Address http://motorola.com
(Search for resonators)
United States Crystal Corp.
Crystek Crystal
Statek Corp.
Fox Electronics
NOTE: Motorola cannot recommend one supplier over another and in no way suggests
that this is a complete listing of crystal manufacturers.
MC145202
18
MOTOROLA
PHASE–LOCKED LOOP — LOW–PASS FILTER DESIGN
(A)
PDout
Kφ KVCO
NC
ωn =
VCO
R
ζ =
C
Kφ KVCOC
N
R
2
=
ωnRC
2
1 + sRC
Z(s) =
sC
NOTE:
For (A), using Kφ in amps per radian with the filter’s impedance transfer function, Z(s), maintains units of volts per radian for the detector/filter
combination. Additional sideband filtering can be accomplished by adding a capacitor C′ across R. The corner ωc = 1/RC′ should be chosen
such that ωn is not significantly affected.
R2
(B)
φR
R1
–
φV
+
R1
R2
ωn =
C
A
VCO
ζ =
Kφ KVCO
NCR1
ωnR2C
2
ASSUMING GAIN A IS VERY LARGE, THEN:
C
F(s) =
R2sC + 1
R1sC
NOTE:
For (B), R1 is frequently split into two series resistors; each resistor is equal to R1 divided by 2. A capacitor CC is then placed from the midpoint
to ground to further filter the error pulses. The value of CC should be such that the corner frequency of this network does not significantly
affect ωn.
DEFINITIONS:
N = Total Division Ratio in Feedback Loop
Kφ (Phase Detector Gain) = IPDout / 2π amps per radian for PDout
Kφ (Phase Detector Gain) = VPD / 2π volts per radian for φV and φR
2π∆fVCO
KVCO (VCO Transfer Function) =
radians per volt
∆VVCO
For a nominal design starting point, the user might consider a damping factor ζ ≈ 0.7 and a natural loop frequency ωn ≈ (2πfR / 50) where fR
is the frequency at the phase detector input. Larger ωn values result in faster loop lock times and, for similar sideband filtering, higher fR–related
VCO sidebands.
Either loop filter (A) or (B) is frequently followed by additional sideband filtering to further attenuate fR–related VCO sidebands. This additional
filtering may be active or passive.
RECOMMENDED READING:
Gardner, Floyd M., Phaselock Techniques (second edition). New York, Wiley–Interscience, 1979.
Manassewitsch, Vadim, Frequency Synthesizers: Theory and Design (second edition). New York, Wiley–Interscience, 1980.
Blanchard, Alain, Phase–Locked Loops: Application to Coherent Receiver Design. New York, Wiley–Interscience, 1976.
Egan, William F., Frequency Synthesis by Phase Lock. New York, Wiley–Interscience, 1981.
Rohde, Ulrich L., Digital PLL Frequency Synthesizers Theory and Design. Englewood Cliffs, NJ, Prentice–Hall, 1983.
Berlin, Howard M., Design of Phase–Locked Loop Circuits, with Experiments. Indianapolis, Howard W. Sams and Co., 1978.
Kinley, Harold, The PLL Synthesizer Cookbook. Blue Ridge Summit, PA, Tab Books, 1980.
Seidman, Arthur H., Integrated Circuits Applications Handbook, Chapter 17, pp. 538–586. New York, John Wiley & Sons.
Fadrhons, Jan, “Design and Analyze PLLs on a Programmable Calculator,” EDN. March 5, 1980.
AN535, Phase–Locked Loop Design Fundamentals, Motorola Semiconductor Products, Inc., 1970.
AR254, Phase–Locked Loop Design Articles, Motorola Semiconductor Products, Inc., Reprinted with permission from Electronic Design,
1987.
AN1253, An Improved PLL Design Method Without ωn and ζ, Motorola Semiconductor Products, Inc., 1995.
MOTOROLA
MC145202
19
THRESHOLD
DETECTOR
+3 V
1 REF
out
2 LD
INTEGRATOR
3 φR
4 φV
ENB
6
LOW–PASS
FILTER
7
8
NC
20
Din 19
18
CLK
5
+3V
REFin
9
10
VPD
OUTPUT A
PDout
OUTPUT B
VDD
GND
Rx
TEST 2
TEST 1
VCC
MCU
17
16
GENERAL–PURPOSE
DIGITAL OUTPUT
15
+3 V
14
13
NC
Q1
NOTE 2
12
fin 11
fin
1000 pF
UHF
VCO
UHF OUTPUT
BUFFER
NOTES:
1. When used, the φR and φV outputs are fed to an external combiner/loop filter. See the Phase–
Locked Loop — Low–Pass Filter Design page for additional information.
2. Transistor Q1 is required only if the standby feature is needed. Q1 permits the bipolar section
of the device to be shut down via use of the general–purpose digital pin, OUTPUT B. If the standby feature is not needed, tie Pin 12 directly to the power supply.
3. For optimum performance, bypass the VCC, VDD, and VPD pins to GND with low–inductance capacitors.
4. The R counter is programmed for a divide value = REFin / fR. Typically, fR is the tuning resolution
required for the VCO. Also, the VCO frequency divided by fR = NT = N x 64 + A; this determines
the values (N, A) that must be programmed into the N and A counters, respectively.
Figure 21. Example Application
DEVICE #1
Din
CLK
ENB
DEVICE #2
OUTPUT A
(DATA OUT)
Din
CLK
ENB
OUTPUT A
(DATA OUT)
CMOS
MCU
OPTIONAL
NOTE: See related Figures 23, 24, and 25.
Figure 22. Cascading Two Devices
MC145202
20
MOTOROLA
MOTOROLA
CLK
ENB
C7
1
C6
2
7
C0
8
X
9
X
10
15
X
16
17
X
18
23
X
24
25
C6
26
31
32
*
Figure 23. Accessing the C Registers of Two
Cascaded MC145202 Devices
CLK
ENB
1
A22
2
7
8
9
15
16
17
23
24
25
31
C0
32
38
39
C REGISTER BITS OF DEVICE #1
IN FIGURE 22
C7
*At this point, the new bytes are transferred to the C registers of both devices and stored. No other registers are affected.
C REGISTER BITS OF DEVICE #2
IN FIGURE 22
X
40
47
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
D in
48
*
A23
A15
A8
A REGISTER BITS OF DEVICE #2
IN FIGURE 22
A16
A7
A0
A23
A9
A8
A REGISTER BITS OF DEVICE #1
IN FIGURE 22
A16
* At this point, the new bytes are transferred to the A registers of both devices and stored. Additionally, for both devices, the
13 LSBs in each of the first buffers of the R registers are transferred to the respective R register’s second buffer. Thus, the
R, N, and A counter can be presented new divide ratios at the same time. The first buffer of each R register is not affected.
Neither C register is affected.
Din
A0
ÇÇ
ÇÇ
ÇÇ
ÇÇ
ÇÇ
ÇÇ
ÇÇ
ÇÇ
ÇÇ
ÇÇ
ÇÇ
ÇÇ
ÇÇ
ÇÇ
ÇÇ
ÇÇ
ÇÇ
ÇÇ
ÇÇ
ÇÇ
ÇÇ
ÇÇ
ÇÇ
ÇÇ
ÇÇ
ÇÇ
ÇÇ
Figure 24. Accessing the A Registers of Two
Cascaded MC145202 Devices
MC145202
21
MC145202
22
1
2
7
R8
8
R7
9
15
16
17
23
24
25
31
32
33
39
R15
R14
R REGISTER BITS OF DEVICE #2
IN FIGURE 22
R0
X
X
R15
R7
R REGISTER BITS OF DEVICE #1
IN FIGURE 22
R8
40
R0
2. Optional load pulse. At this point, the bits R0 through R12 are transfered to the second buffer of the R register. The R counter begins dividing
by the new ratio after completing the rest of the present count cycle. CLK must be low during the ENB pulse, as shown. The C and A registers
are not affected. The first buffer of the R register is not affected. Also, see note of Figure 24 for an alternate method of loading the second
buffer in the R register.
NOTES APPLICABLE TO EACH DEVICE:
1. At this point, bits R13, R14 and R15 are stored and sent to the ‘‘OSC or 4–Stage Divider” block in the Block Diagram. Bits R0 through
R12 are loaded into the first buffer in the double–buffered section of the R register. Therfore, the R counter divide is not altered yet and
retains the previous ratio loaded. The C and A registers are not affected.
Din
CLK
ENB
Note 1 Note 2
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
ÇÇÇ
Figure 25. Accessing the R Registers of Two Cascaded
MC145202 Devices
MOTOROLA
PACKAGE DIMENSIONS
F SUFFIX
SOG (SMALL OUTLINE GULL–WING) PACKAGE
CASE 751J–01
–A
–
20
11
1
10
G
S 10 PL
0.13 (0.005)
B
M
NOTES:
1. DIMENSIONS “A” AND “B” ARE DATUMS AND
“T” IS A DATUM SURFACE.
2. DIMENSIONING AND TOLERANCING PER
ANSI Y14.5M, 1982.
3. CONTROLLING DIM: MILLIMETER.
4. DIMENSION A AND B DO NOT INCLUDE MOLD
PROTRUSION.
5. MAXIMUM MOLD PROTRUSION 0.15 (0.006)
PER SIDE.
–B
–
M
J
C
0.13 (0.005)
M
0.10 (0.004)
–T
–
L
D 20 PL
T B
S
A
DIM
A
B
C
D
G
J
K
L
M
S
M
SEATING
PLANE
S
K
MILLIMETERS
MIN
MAX
12.55 12.80
5.10
5.40
—
2.00
0.35
0.45
1.27 BSC
0.18
0.23
0.55
0.85
0.05
0.20
0°
7°
7.40
8.20
INCHES
MIN
MAX
0.494 0.504
0.201 0.213
—
0.079
0.014 0.018
0.050 BSC
0.007 0.009
0.022 0.033
0.002 0.008
0°
7°
0.291 0.323
DT SUFFIX
TSSOP (THIN SHRUNK SMALL OUTLINE PACKAGE)
CASE 948D–03
A
20X
0.200 (0.004)
20
NOTES:
1. DIMENSIONING AND TOLERANCING PER ANSI
Y14.5M, 1982.
2. CONTROLLING DIMENSION: MILLIMETER.
3. DIMENSION A DOES NOT INCLUDE MOLD
FLASH, PROTRUSIONS OR GATE BURRS.
MOLD FLASH OR GATE BURRS SHALL NOT
EXCEED 0.15 (0.006) PER SIDE.
4. DIMENSION B DOES NOT INCLUDE
INTERLEAD FLASH OR PROTRUSION.
INTERLEAD FLASH OR PROTRUSION SHALL
NOT EXCEED 0.25 (0.010) PER SIDE.
5. DIMENSION K DOES NOT INCLUDE DAMBAR
PROTRUSION. ALLOWABLE DAMBAR
PROTRUSION SHALL BE 0.08 (0.003) TOTAL IN
EXCESS OF THE K DIMENSION AT MAXIMUM
MATERIAL CONDITION.
6. TERMINAL NUMBERS ARE SHOWN FOR
REFERENCE ONLY.
7. DIMENSIONS A AND B ARE TO BE
DETERMINED AT DATUM PLANE –U–.
K REF
M
T
11
L
B
PIN 1
IDENTIFICATION
10
1
C
-U0.100 (0.004)
-T-
D
SEATING
PLANE
H
G
A
K
K1
J1
M
J
SECTION A-A
MOTOROLA
A
F
DIM
A
B
C
D
F
G
H
J
J1
K
K1
L
M
MILLIMETERS
MIN
MAX
–––
6.60
4.30
4.50
–––
1.20
0.05
0.25
0.45
0.55
0.65 BSC
0.275
0.375
0.09
0.24
0.09
0.18
0.16
0.32
0.16
0.26
6.30
6.50
0°
10 °
INCHES
MIN
MAX
–––
0.260
0.169
0.177
–––
0.047
0.002
0.010
0.018
0.022
0.026 BSC
0.011
0.015
0.004
0.009
0.004
0.007
0.006
0.013
0.006
0.010
0.248
0.256
0°
10 °
MC145202
23
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. “Typical” 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.
Mfax is a trademark of Motorola, Inc.
How to reach us:
USA / EUROPE / Locations Not Listed: Motorola Literature Distribution;
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Mfax: [email protected] – TOUCHTONE 1–602–244–6609
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– US & Canada ONLY 1–800–774–1848
– http://sps.motorola.com/mfax/
HOME PAGE: http://motorola.com/sps/
MC145202
24
◊
JAPAN: Nippon Motorola Ltd.: SPD, Strategic Planning Office, 141,
4–32–1 Nishi–Gotanda, Shagawa–ku, Tokyo, Japan. 03–5487–8488
ASIA/PACIFIC: Motorola Semiconductors H.K. Ltd.; 8B Tai Ping Industrial Park,
51 Ting Kok Road, Tai Po, N.T., Hong Kong. 852–26629298
CUSTOMER FOCUS CENTER: 1–800–521–6274
MC145202/D
MOTOROLA