TI CDCM7005ZVAT 3.3-v high performance clock synchronizer and jitter cleaner Datasheet

CDCM7005
www.ti.com
SCAS793A – JUNE 2005 – REVISED JUNE 2005
3.3-V HIGH PERFORMANCE CLOCK SYNCHRONIZER AND JITTER CLEANER
GND
GND
GND
GND
GND
GND
C
VBB
GND
AVCC
AVCC
AVCC
AVCC
AVCC
GND
STATUS_
REF or
PRI_SEC_
CLK
STATUS_
D
VCXO_IN
GND
GND
GND
GND
GND
VCXO
or
VCC
I_REF_CP
E
VCXO_IN
GND
VCC
VCC
VCC
VCC
VCC
VCC
F
Y0A
GND
GND
GND
GND
GND
VCC
Y4B
G
Y0B
VCC
VCC
VCC
VCC
VCC
VCC
Y4A
H
PD
Y1A
Y1B
Y2A
Y2B
Y3A
Y3B
RESET
or
HOLD
SEC_REF
CTRL_DATA
PLL_LOCK
CTRL_CLK
AVCC
AVCC
CTRL_LE
AVCC
P0022-01
36 35 34 33 32 31 30 29 28 27 26 25
24
37
GND
AVCC
38
23
AVCC
39
22
STATUS_REF or
PRI_SEC_CLK
STATUS_VCXO or
I_REF_CP
VBB
40
21
VCC
VCC
41
20
VCC
VCXO_IN
42
19
VCC
VCXO_IN
43
18
VCC
VCC
44
17
Y4B
VCC
45
16
Y4A
Y0A
46
15
VCC
Y0B
47
14
VCC
48
1
2
3
4
5
6
7
8
9
13
10 11 12
RESET or
HOLD
VCC
Y3A
Thermal Pad
must be
soldered to GND
Y3B
•
•
•
SEC_REF
VCC
•
B
VCC
•
CTRL_
DATA PLL_LOCK
Y2A
•
•
8
Y2B
•
7
PRI_REF REF_SEL VCC_CP CP_OUT CTRL_LE CTRL_CLK
CP_OUT
•
6
VCC
•
5
VCC
•
•
4
A
NC
•
3
VCC_CP
•
2
Y1A
•
1
Y1B
•
PIN ASSIGNMENTS (TOP VIEW)
PRI_REF
•
or 48-Pin QFN (RGZ)
Industrial Temperature Range –40°C to 85°C
REF_SEL
•
•
PD
•
High Performance LVPECL and LVCMOS PLL
Clock Synchronizer
Two Reference Clock Inputs (Primary and
Secondary Clock) for Redundancy Support
With Manual or Automatic Selection
Accepts LVCMOS Input Frequencies Up to
200 MHz
VCXO_IN Clock is Synchronized to One of the
Two Reference Clocks
VCXO_IN Frequencies Up to 2.2 GHz
(LVPECL)
Outputs Can Be a Combination of LVPECL
and LVCMOS (Up to Five Differential LVPECL
Outputs or Up to 10 LVCMOS Outputs)
Output Frequency is Selectable by x1, /2, /3,
/4, /6, /8, /16 on Each Output Individually
Efficient Jitter Cleaning From Low PLL Loop
Bandwidth
Low Phase Noise PLL Core
Programmable Phase Offset (PRI_REF and
SEC_REF to Outputs)
Wide Charge Pump Current Range From 200
µA to 3 mA
Dedicated Charge Pump Supply (VCC_CP) for
Wide Tuning Voltage Range VCOs
Presets Charge Pump to VCC_CP/2 for Fast
Center-Frequency Setting of VC(X)O
Analog and Digital PLL Lock Indication
Provides VBB Bias Voltage Output for
Single-Ended Input Signals (VCXO_IN)
Frequency Hold-Over Mode Improves
Fail-Safe Operation
Power-Up Control Forces LVPECL Outputs to
3-State at VCC < 1.5 V
SPI Controllable Device Setting
3.3-V Power Supply
Packaged in 64-Pin BGA (0,8 mm Pitch – ZVA)
VCC
FEATURES
•
P0023-01
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2005, Texas Instruments Incorporated
CDCM7005
www.ti.com
SCAS793A – JUNE 2005 – REVISED JUNE 2005
DESCRIPTION
The CDCM7005 is a high-performance, low phase noise and low skew clock synchronizer that synchronizes a
VCXO (voltage controlled crystal oscillator) or VCO (voltage controlled oscillator) frequency to one of the two
reference clocks. The programmable pre-divider M and the feedback-dividers N and P give a high flexibility to the
frequency ratio of the reference clock to VC(X)O:
• VC(X)O_IN / PRI_REF = (N x P) / M or
• VC(X)O_IN / SEC_REF = (N x P) / M
VC(X)O_IN clock operates up to 2.2 GHz. Through the selection of external VC(X)O and loop filter components,
the PLL loop bandwidth and damping factor can be adjust to meet different system requirements.
The CDCM7005 can lock to one of two reference clock inputs (PRI_REF and SEC_REF), supports frequency
hold-over mode and fast-frequency-locking for fail-safe and increased system redundancy. The outputs of the
CDCM7005 are user definable and can be any combination of up to five LVPECL outputs or up to 10 LVCMOS
outputs. The LVCMOS outputs are arranged in pairs (Y0A:Y0B, Y1A:Y1B, …), so that each pair has the same
frequency. But each output can be separately inverted and disabled. The built in synchronization latches ensure
that all outputs are synchronized for low output skew.
All device settings, like outputs signaling, divider value, input selection, and many more, are programmable by
SPI (3-wire serial peripheral interface). SPI allows individually control of the device settings.
The device operates in 3.3-V environment and is characterized for operation from –40°C to 85°C.
2
CDCM7005
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SCAS793A – JUNE 2005 – REVISED JUNE 2005
FUNCTIONAL BLOCK DIAGRAM
VCC
AVCC
VCC_CP
Selected REF Signal
REF_SEL
Manual &
Automatic
CLK Select
STATUS_REF/
PRI_SEC_CLK
STATUS_VCXO/
I_REF_CP
freq. Detect
> 2 Mhz
PLL_LOCK
freq. Detect
> 2 Mhz
LVCMOS
SEC_REF
R EF_M UX
PRI_REF
Reference
Clock
Feedback
Clock
Progr. Delay
M
Progr. Divider
Progr. Delay
N
Progr. Divider
LOCK
HOLD
PFD
Charge
Pump
10
M 2
N 2
Current
Reference
SPI LOGIC
CTRL_LE
CP_OUT
12
CTRL_DATA
CTRL_CLK
PECL
to
LVCMOS
LV
CMOS
RESET or
HOLD
FB_MUX
Y0_MUX
Y0A
PD
LV
PECL
Y0B
LV
CMOS
LV
CMOS
Y1_MUX
Y1A
÷1
LV
PECL
Y1B
÷2
LV
CMOS
÷3
LV
CMOS
÷4
VCXO_IN
PECL
INPUT
Y2A
Y2_MUX
VCXO_IN
÷6
LV
PECL
Y2B
/8
÷8
LV
CMOS
÷ 16
LV
CMOS
90o 90o
Y3A
Y3_MUX
÷4
÷8
P16-Div
LV
PECL
P Divider
Y3B
LV
CMOS
LV
CMOS
Bias Generator
VCC – 1.3V
Y4A
Y4_MUX
VBB
LV
PECL
Y4B
LV
CMOS
GND
B0057-01
3
CDCM7005
www.ti.com
SCAS793A – JUNE 2005 – REVISED JUNE 2005
Table 1. PIN ASSINGMENT
TERMINAL
NAME
I/O
DESCRIPTION
BGA
QFN
VCC
D7, E3,
E4, E5,
E6, E7,
E8, F7,
G2, G3,
G4, G5,
G6, G7
2, 5, 6,
9, 10,
13, 15,
18, 19,
20, 21,
41, 44,
45; 48
Power
3.3-V supply. There is no internal connection between VCC and AVCC. It is
recommended that AVCC use its own supply filter.
GND
B2, B3,
B4, B5,
B6, B7,
B8, C2,
D2, D3,
D4, D5,
D6, E2,
F2, F3,
F4, F5,
F6
Thermal
pad and
pin 24
Ground
Ground
AVCC
C3, C4,
C5, C6,
C7
27, 30,
32, 38,
39
Analog
Power
3.3-V analog power supply. There is no internal connection between AVCC and
VCC. It is recommended that AVCC use its own supply filter.
VCC_CP
A3
33
Power
This is the charge pump power supply pin used to have the same supply as the
external VCO. It can be set from 2.3 V to 3.6 V.
CTRL_LE
A5
29
I
LVCMOS input, control latch enable for serial programmable Interface (SPI), with
hysteresis
CTRL_CLK
A6
28
I
LVCMOS input, serial control clock input for SPI, with hysteresis
CTRL_DATA
A7
26
I
LVCMOS input, serial control data input for SPI, with hysteresis
I
LVCMOS input, asynchronous power down (PD) signal. This pin is low active and
can be activated external or by the corresponding bit in the SPI register (in case of
logic high, the SPI setting is valid). Switches the device into power-down mode.
Resets M- and N-Divider, 3-states charge pump, STATUS_REF, or
PRI_SEC_CLK pin, STATUS_VCXO or I_REF_CP pin, PLL_LOCK pin, VBB pin
and all Yx outputs. Sets the SPI register to default value; has internal 150-kΩ
pullup resistor.
PD
H1
1
This LVCMOS input can be programmed (SPI) to act as HOLD or RESET. RESET
is the default function. This pin is low active and can be activated external or via
the corresponding bit in the SPI register. In case of RESET, the charge pump (CP)
is switched to 3-state and all counters (N, M, P) are reset to zero (the initial divider
settings are maintained in SPI registers). The LVPECL outputs are static low and
high respectively and the LVCMOS outputs are all low or high if inverted. RESET
is not edge triggered and should have a pulse duration of at least 5 ns.
RESET or
HOLD
H8
VCXO_IN
E1
43
I
VCXO LVPECL input
VCXO_IN
D1
42
I
Complementary VCXO LVPECL input
PRI_REF
A1
36
I
LVCMOS input for the primary reference clock, with an internal 150-kΩ pullup
resistor and input hysteresis.
SEC_REF
B1
37
I
LVCMOS input for the secondary reference clock, with an internal 150-kΩ pullup
resistor and input hysteresis.
14
I
In case of HOLD, the CP is switched in to 3-state mode only. After HOLD is
released and with the next valid reference clock cycle the charge pump is
switched back in to normal operation (CP stays in 3-state as long as no reference
clock is valid). During HOLD, the P divider and all outputs Yx are at normal
operation. This mode allows an external control of the frequency hold-over mode.
The input has an internal 150-kΩ pullup resistor.
REF_SEL
A2
35
I
LVCMOS reference clock selection input. In the manual mode the REF_SEL
signal selects one of the two input clocks:
REF_SEL [1]: PRI_REF is selected;
REF_SEL [0]: SEC_REF is selected;
The input has an internal 150-kΩ pullup resistor.
CP_OUT
A4
31
O
Charge pump output
4
CDCM7005
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SCAS793A – JUNE 2005 – REVISED JUNE 2005
Table 1. PIN ASSINGMENT (continued)
TERMINAL
NAME
VBB
BGA
QFN
C1
40
I/O
DESCRIPTION
Bias voltage output to be used to bias unused complementary input VCXO_IN for
single ended signals. The output of VBB is VCC– 1.3 V. The output current is
limited to about 1.5 mA.
O
This output can be programmed (SPI) to provide either the STATUS_REF or
PRI_SEC_CLK information. This pin is set high if one of the STATUS conditions is
valid. STATUS_REF is the default setting.
STATUS_REF or
PRI_SEC_CLK
C8
23
In case of STATUS_REF, the LVCMOS output provides the Status of the
Reference Clock. If a reference clock with a frequency above 2 MHz is provided to
PRI_REF or SEC_REF STATUS_REF will be set high.
O
In case of PRI_SEC_CLK, the LVCMOS output indicates whether the primary
clock [high] or the secondary clock [low] is selected.
This LVCMOS output can be programmed (SPI) to provide either the
STATUS_VCXO information or serve as current path for the charge pump (CP).
STATUS_VCXO is the default setting.
STATUS_VCXO
or I_REF_CP
D8
22
In case of STATUS_VCXO, the LVCMOS output provides the status of the VCXO
input (frequencies above 2 MHz are interpreted as valid clock; active high).
O
In case of I_REF_CP, it provides the current path for the external reference
resistor (12 kΩ± 1%) to support an accurate charge pump current, optional. Do not
use any capacitor across this resistor to prevent noise coupling via this node. If
the internal 12 kΩ is selected (default setting), this pin can be left open.
LVCMOS output for PLL_LOCK information. This pin is set high if the PLL is in
lock (see feature description). This output can be programmed to be digital lock
detect or analog lock detect (see feature description).
PLL_LOCK
A8
25
The PLL is locked (set high), if the rising edge either of PRI_REF or SEC_REF
clock and VCXO_IN clock at the phase frequency detector (PFD) are inside the
lock detect window for a predetermined number of successive clock cycles.
I/O
The PLL is out-of-lock (set low), if the rising edge of either the PRI_REF or
SEC_REF) clock and VCXO_IN clock at the PFD are outside the lock detect
window or if a cycle-slip occurs.
Both, the lock detect window and the number of successive clock cycles are user
definable (via SPI).
Y0A:Y0B
Y1A:Y1B
Y2A:Y2B
Y3A:Y3B
Y4A:Y4B
F1, G1,
H2, H3,
H4, H5,
H6, H7,
G8, F8
46, 47,
3, 4,
7, 8,
11,12,
16, 17
The outputs of the CDCM7005 are user definable and can be any combination of
up to five LVPECL outputs or up to 10 LVCMOS outputs. The outputs are
selectable via SPI (Word 1, Bit 2-6). The power-up setting is all outputs are
LVPECL.
O
ABSOLUTE MAXIMUM RATINGS
over operating free-air temperature range (unless otherwise noted) (1)
VALUE / UNIT
(2)
VCC, AVCC, VCC_CP
Supply voltage range
VI
Input voltage range
VO
Output voltage range
(3)
–0.5 V to VCC + 0.5 V
IOUT
Output current for LVPECL/LVCMOS outputs
(0 < VO < VCC)
±50 mA
IIN
Input current (VI < 0, VI > VCC)
Tstg
Storage temperature range
TJ
Maximum junction temperature
(1)
(2)
(3)
(3)
–0.5 V to 4.6 V
–0.5 V to VCC + 0.5 V
±20 mA
–65°C to 150°C
125°C
Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratings
only, and functional operation of the device at these or any other conditions beyond those indicated under recommended operating
conditions is not implied. Exposure to absolute–maximum–rated conditions for extended periods may affect device reliability.
All supply voltages have to be supplied at the same time.
The input and output negative voltage ratings may be exceeded if the input and output clamp-current ratings are observed.
5
CDCM7005
www.ti.com
SCAS793A – JUNE 2005 – REVISED JUNE 2005
Package Thermal Resistance for RGZ (QFN) Package (1) (2)
(1)
(2)
(3)
Airflow (lfm)
θJA (°C/W)
θJC (°C/W)
22.4
θJP (°C/W)
ψJT (°C/W)
(3)
0
29.9
150
24.7
1.5
0.2
0.2
250
23.2
0.2
500
21.5
0.3
The package thermal impedance is calculated in accordance with JESD 51 and JEDEC2S2P (high-k board).
Connected to GND with nine thermal vias (0,3 mm diameter).
θJP (junction pad) is used for the QFN package, because the main heat flow is from the junction to the GND pad of the QFN.
Package Thermal Resistance for ZVA (BGA) Package (1)
(1)
(2)
Airflow (m/s)
θJA (°C/W)
θJC (°C/W)
θJB (°C/W)
0 m/s
53.9
28.3
ψJT (°C/W)
1 m/s
49.8
0.7
2 m/s
48.5
0.8
(2)
38.6
0.7
The package thermal impedance is calculated in accordance with JESD 51 and JEDEC2S2P (high-k board).
θJB (junction board) is used for the BGA package, because the main heat flow is from junction to the board.
RECOMMENDED OPERATING CONDITIONS
VCC, AVCC
VCC_CP
Supply voltage
MIN
NOM
MAX
3
3.3
3.6
2.3
VIL
Low-level input voltage LVCMOS, see
(1)
VIH
High-level input voltage LVCMOS, see
(1)
IOH
High-level output current LVCMOS (includes all status pins)
IOL
Low-level output current LVCMOS (includes all status pins)
VI
Input voltage range LVCMOS
VIL
UNIT
V
VCC
0.3 VCC
V
0.7 VCC
V
–8
mA
8
mA
0
3.6
V
Low-level input voltage LVPECL
VCC–1.81
VCC–1.475
V
VIH
High-level input voltage LVPECL
VCC–1.26
VCC–0.88
V
VINPP
Input amplitude LVPECL (VVCXO_IN– VVCXO_IN) (2)
0.5
1.3
V
VIC
Common-mode input voltage LVPECL
1
VCC–0.3
V
TA
Operating free-air temperature
–40
85
°C
(1)
(2)
VIL and VIH are required to maintain ac specifications; the actual device function tolerates a smaller input level of 1V, if an ac-coupling to
VCC/2 is provided.
VINPP minimum and maximum is required to maintain ac specifications; the actual device function tolerates at a minimum VINPP
of 150 mV.
TIMING REQUIREMENTS
over recommended ranges of supply voltage, load and operating free air temperature
PARAMETER
MIN
TYP
MAX
UNIT
200
MHz
PRI_REF/SEC_REF_IN REQUIREMENTS
fREF_IN
LVCMOS primary or secondary reference clock frequency (1) (2)
tr/ tf
Rise and fall time of PRI_REF or SEC_REF signals from 20% to 80% of VCC
dutyREF
Duty cycle of PRI_REF or SEC_REF at VCC/2
0
4
40%
60%
0
2200
ns
VCXO_IN, VCXO_IN REQUIREMENTS
fVCXO_IN
(1)
(2)
(3)
6
VCXO clock frequency (3)
MHz
At Reference Clock less than 2 MHz, the device stays in normal operation mode but the frequency detection circuitry resets the
STATUS_REF signal to low. In this case, the status of the STATUS_REF is no longer relevant.
fREF_IN can be up to 250 MHz in typical operating mode (25°C / 3.3-V VCC).
If the Feedback Clock (derives from VCXO input) is less than 2 MHz, the device stays in normal operation mode but the frequency
detection circuitry resets the STATUS_VCXO signal and PLL_LOCK signal to low. Both status signals are no longer relevant. This
effects the HOLD-over function as well, as the PLL_LOCK signal is no longer valid!
CDCM7005
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SCAS793A – JUNE 2005 – REVISED JUNE 2005
TIMING REQUIREMENTS (continued)
over recommended ranges of supply voltage, load and operating free air temperature
PARAMETER
MIN
tr/ tf
Rise and fall time 20% to 80% of VINPP at 80 MHz to 800 MHz (4)
dutyVCXO
Duty cycle of VCXO clock
TYP
MAX
3
40%
UNIT
ns
60%
SPI/CONTROL REQUIREMENTS (see Figure 14)
fCTRL_CLK
CTRL_CLK frequency
tsu1
CTRL_DATA to CTRL_CLK setup time
10
20
MHz
ns
th2
CTRL_DATA to CTRL_CLK hold time
10
ns
t3
CTRL_CLK high duration
25
ns
t4
CTRL_CLK low duration
25
ns
tsu5
CTRL_LE to CTRL_CLK setup time
10
ns
tsu6
CTRL_CLK to CTRL_LE setup time
10
ns
t7
CTRL_LE pulse width
20
tr/ tf
Rise and fall time of CTRL_DATA CTRL_CLK, CTRL_LE from 20% to 80% of VCC
ns
4
ns
4
ns
PD, RESET, HOLD, REF_SEL REQUIREMENTS
tr / tf
(4)
Rise and fall time of the PD, RESET, HOLD, REF_SEL signal from 20% to 80% of VCC
Use a square wave for lower frequencies (< 80 MHz).
DEVICE CHARACTERISTICS
over recommended operating free-air temperature range (unless otherwise noted)
PARAMETER
TYP (1)
MAX
UNIT
fVCXO = 245.76 MHz,
fREF_IN = 30.72 MHz,
PFD = 240 kHz, ICP = 2 mA, all outputs
are LVPECL and Div-by-8 (load, see
Figure 13)
210
260
mA
fVCXO = 245.76 MHz,
fREF_IN = 30.72 MHz,
PFD = 240 kHz, ICP = 2 mA, All outputs
are LVCMOS and Div-by-8 (load, 10 pF)
120
150
mA
fIN = 0 MHz, VCC = 3.6 V, AVCC = 3.6 V,
VCC_CP = 3.6 V,
VI = 0 V or VCC
100
300
µA
±40
µA
±100
µA
TEST CONDITIONS
MIN
OVERALL
ICC_LVPECL
Supply current (ICC over frequency see
Figure 1 through Figure 4)
ICC_LVCMOS
ICCPD
Power-down current
IOZ
High-impedance state output current
for Yx outputs
VO = 0 V or VCC– 0.8 V
VI_REF_CP
Voltage on I_REF_CP (external current
path for accurate charge pump current)
12 kΩ to GND at pin D8 (BGA), pin 22
(QFN)
VBB
Output reference voltage
VCC = 3 V – 3.6 V; IBB = –0.2 mA
CO
Output capacitance for Yx
VCC = 3.3 V, VO = 0 V or VCC
Input capacitance at PRI_REF and
SEC_REF
VI = 0 V or VCC, VI = 0 V or VCC
Input capacitance at CTRL_LE,
CTRL_CLOCK, CTRL_DATA
VI = 0 V or VCC
CI
VO = 0 V or VCC
1.21
V
VCC–1.3
V
2
pF
2.7
pF
2
LVCMOS
fclk
Output frequency, see
and Figure 7
VIK
II
(1)
(2)
(3)
(2), (3),
Figure 6,
Load = 5 pF to GND, 1 kΩ to VCC, 1 kΩ
to GND
250
MHz
LVCMOS input clamp voltage
VCC = 3 V, II = –18 mA
–1.2
V
LVCMOS input current for CTRL_LE,
CTRL_CLK, CTRL_DATA
VI = 0 V or VCC, VCC = 3.6 V
±5
µA
All typical values are at VCC = 3.3 V, temperature = 25°C.
fclk can be up to 400 MHz in the typical operating mode (25°C / 3.3-V VCC). The total power consumption limit of 700 mW for the BGA
package can be violated if several LVCMOS outputs switch at high frequency (see Figure 3 and Figure 4).
Operating the LVCMOS or LVPECL output above the maximum frequency will not cause a malfunction to the device, but the output
signal swing may no longer meet the output specification.
7
CDCM7005
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SCAS793A – JUNE 2005 – REVISED JUNE 2005
DEVICE CHARACTERISTICS (continued)
over recommended operating free-air temperature range (unless otherwise noted)
PARAMETER
TEST CONDITIONS
IIH
LVCMOS input current for PD, RESET,
HOLD, REF_SEL, PRI_REF,
SEC_REF, (see (4))
VI = VCC, VCC = 3.6 V
IIL
LVCMOS input current for PD, RESET,
HOLD, REF_SEL, PRI_REF,
SEC_REF, (see (4))
VI = 0 V, VCC = 3.6 V
VOH
High-level output voltage for LVCMOS
outputs
VCC = min to max,
IOH = –100 µA
VCC = 3 V, IOH = –6 mA
VCC = 3 V, IOH = –12 mA
MIN
TYP (1)
–15
MAX
UNIT
5
µA
–35
µA
VCC–0.1
V
2.4
2
VCC = min to max,
IOL = 100 µA
0.1
VCC = 3 V, IOL = 6 mA
0.5
VOL
Low-level output voltage for LVCMOS
outputs
IOH
High-level output current
VCC = 3.3 V, VO = 1.65 V
–30
mA
IOL
Low-level output current
VCC = 3.3 V, VO = 1.65 V
33
mA
tpho
Phase offset (REF_IN to Y output) (5)
VREF_IN = VCC/2, Y = VCC/2,
see Figure 11, Load = 10 pF
1.8
ns
tsk(p)
LVCMOS pulse skew, see Figure 10
Crosspoint to VCC/2 load, see Figure 12
tpd(HL)
Propagation delay from VCXO_IN to
Yx, see Figure 10
Crosspoint to VCC/2,
Load = 10 pF, see Figure 12 (PLL
bypass mode)
tsk(o)
LVCMOS single-ended output skew,
see (6) and Figure 10
All outputs have the same divider ratio
55
Outputs have different divider ratios
70
Duty cycle
LVCMOS
VCC/2 to VCC/2
Output rise/fall slew rate
20% to 80% of swing (load
see Figure 12)
VCC = 3 V, IOL = 12 mA
tpd(LH)
tslew-rate
V
0.8
2
2.5
49%
2.4
150
ps
3
ns
ps
51%
3.5
V/ns
LVPECL
(7)
fclk
Output frequency, see
II
LVPECL input current
and Figure 5
VI = 0 V or VCC
VOH
LVPECL high-level output voltage
Load, See Figure 13
VOL
LVPECL low-level output voltage
Load, See Figure 13
|VOD|
Differential output voltage
See Figure 9 and load, see Figure 13
500
tpho
Phase offset (REF_IN to Y output) (6)
VREF_IN = VCC/2 to cross point of Y,
see Figure 11
–200
tpd(LH)
tpd(HL)
Propagation delay time, VCXO_IN to
Yx, see Figure 10
Cross point-to-cross point, load
see Figure 13
tsk(p)
LVPECL pulse skew, see Figure 10
tsk(o)
LVPECL output skew (6)
tr / tf
Rise and fall time
CI
Input capacitance at VCXO_IN,
VCXO_IN
Load, see Figure 13
0
1500
MHz
±20
µA
VCC–1.18
VCC–0.81
V
VCC–2
VCC–1.55
V
mV
100
ps
640
ps
Cross point-to-cross point, load
see Figure 13
10
ps
Load see Figure 13, all outputs have the
same divider ratio
20
Load see Figure 13, outputs have
different divider ratios
50
20% to 80% of VOUTPP, see Figure 9
340
490
ps
120
170
220
1.5
ps
pF
LVCMOS-TO-LVPECL
tsk(P_C)
(4)
(5)
(6)
(7)
(8)
8
Output skew between LVCMOS and
LVPECL outputs, see (8) and Figure 10
Cross point to VCC/2; load,
see Figure 12 and Figure 13
1.7
2
2.4
ns
These inputs have an internal 150-kΩ pullup resistor.
This is valid only for the same frequency of REF_IN clock and Y output clock. It can be adjusted by the SPI controller (reference delay M
and VCXO delay N).
The tsk(o) specification is only valid for equal loading of all outputs.
Operating the LVCMOS or LVPECL output above the maximum frequency will not cause a malfunction to the device, but the output
signal swing may no longer meet the output specification.
The phase of LVCMOS is lagging in reference to the phase of LVPECL.
CDCM7005
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SCAS793A – JUNE 2005 – REVISED JUNE 2005
DEVICE CHARACTERISTICS (continued)
over recommended operating free-air temperature range (unless otherwise noted)
PARAMETER
TEST CONDITIONS
TYP (1)
MIN
MAX
UNIT
PLL ANALOG LOCK
IOH
High-level output current
VCC = 3.6 V, VO = 1.8 V
–110
µA
IOL
Low-level output current
VCC = 3.6 V, VO = 1.8 V
110
µA
IOZH
LOCK
High-impedance state output current
for PLL LOCK output (9)
VO = 3.6 V (PD is set low)
IOZL
LOCK
High-impedance state output current
for PLL LOCK output (9)
VO = 0 V (PD is set low)
VIT+
Positive input threshold voltage
VCC = min to max
VCC×0.55
V
VIT–
Negative input threshold voltage
VCC = min to max
VCC×0.35
V
45
65
µA
±5
µA
PHASE DETECTOR
fCPmax
Maximum charge pump frequency
Default PFD pulse width delay
ICP
Charge pump sink/source current
range (10)
VCP = 0.5 VCC_CP
ICP3St
Charge pump 3-state current
0.5 V < VCP < VCC_CP– 0.5 V
100
MHz
±3
mA
10
nA
CHARGE PUMP
±0.2
VCP = 0.5 VCC_CP, internal reference
resistor, SPI default settings
ICPA
ICP absolute accuracy
10%
VCP = 0.5 VCC_CP, external reference
resistor 12 kΩ (1%) at I_REF_CP, SPI
default settings
5%
ICPM
Sink/source current matching
0.5 V < VCP < VCC_CP– 0.5 V, SPI default
settings
IVCPM
ICP vs VCP matching
0.5 V < VCP < VCC_CP– 0.5 V
2.5%
5%
(9) Lock output has an 80-kΩ pulldown resistor.
(10) Defined by SPI settings.
TYPICAL CHARACTERISTICS
LVPECL SUPPLY CURRENT
vs
NUMBER OF ACTIVE OUTPUTS
250
All Output Pairs Active (4 div-by-8 / 1 div-by-3)
230
∆ For div-by-3/6
ICC − Supply Current − mA
210
190
All Output Pairs Active (div-by-8)
170
All Output Pairs Active (div-by-1)
150
VCC = 3.3 V
TA = 25°C
∆ for div-by-2/4/8/16
130
One Output Pair Active (div-by-8)
110
90
∆ For 1 Output Pair
No Output Active
70
50
50
250
450
650
850
1050
1250
1450
1650
1850
2050
VCXO_IN Input Frequency − MHz
G001
A.
If div-by-2/4/8/16 is activated for one or more outputs, '∆ for div-by-2/4/8/16' has to be added to ICC of div-by-1. If
div-by-3 or div-by-6 is activated, '∆ for div-by-2/4/8/16' and '∆ for div-by3/6' has to be added to ICC of div-by-1.
Figure 1.
9
CDCM7005
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SCAS793A – JUNE 2005 – REVISED JUNE 2005
TYPICAL CHARACTERISTICS (continued)
LVPECL DEVICE POWER CONSUMPTION
vs
NUMBER OF ACTIVE OUTPUTS
PDEV − Device Power Consumption − mW
750
VCC = 3.3 V
TA = 25°C
650
All Output Pairs Active (4 div-by-8 / 1 div-by-3)
550
All Output Pairs Active (div-by-8)
450
All Output Pairs Active (div-by-1)
One Output Pair Active (div-by-8)
350
250
150
No Output Active
50
50
250
450
650
850
1050
1250
1450
1650
1850
2050
VCXO_IN Input Frequency − MHz
G002
Figure 2.
LVCMOS SUPPLY CURRENT / DEVICE POWER CONSUMPTION
vs
NUMBER OF ACTIVE OUTPUTS (Load = 5 pF)
Icc − Supply Current − mA
200
all outputs active div−by−3
700
600
for div−by−3/6
150
all outputs active div−by−1 one output pair active div−by−1
100
500
400
300
for 1 output
50
for 1 output pair
200
100
one output active div−by−1
no output active
0
50
100
150
200
250
Output Frequency − MHz
10
A.
To estimate ICC with different P-divider settings use '∆ for div-by-2/4/8/16' and '∆ for div-by-3/6' of Figure 1.
B.
It is not recommended to exceed power dissipation of 700 mW for the BGA package at TA 85°C.
Figure 3.
0
300
PDEV − Power Device Consumption
− mW
800
Vcc = 3.3V
TA = 25C
load = 5 pF
CDCM7005
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SCAS793A – JUNE 2005 – REVISED JUNE 2005
TYPICAL CHARACTERISTICS (continued)
LVCMOS SUPPLY CURRENT / DEVICE POWER CONSUMPTION
vs
NUMBER OF ACTIVE OUTPUTS (Load = 10 pF)
900
VCC = 3.3 V
TA = 25C
Load = 10 pF
all outputs active div−by−3
800
700
200
600
for div−by−3/6
500
150
all outputs active div−by−1
400
one output pair active div−by−1
100
300
for 1 output
50
for 1 output pair
PDEV − Device Power
Consumption − mW
Icc − Supply Current − mA
250
200
100
one output active div−by−1
no output active
0
40
60
80
100
120
140
160
180
200
220
240
260
280
0
300
Output Frequency − MHz
A.
To estimate ICC with different P-divider settings use '∆ for div-by-2/4/8/16' and '∆ for div-by-3/6' of Figure 1.
B.
It is not recommended to exceed power dissipation of 700 mW for the BGA package at TA 85°C.
Figure 4.
DIFFERENTIAL LVPECL OUTPUT VOLTAGE
vs
OUTPUT FREQUENCY
VOD − Differential Output Voltage − V
0.90
VCC = 3.3 V
TA = 25°C
Termination = 50 to VCC − 2 V
0.85
0.80
0.75
0.70
0.65
0.60
0.55
0.50
50
250
450
650
850
1050
1250
fOut − Output Frequency − MHz
1450
1650
1850
G005
Figure 5.
11
CDCM7005
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SCAS793A – JUNE 2005 – REVISED JUNE 2005
TYPICAL CHARACTERISTICS (continued)
LVCMOS OUTPUT SWING
vs
FREQUENCY
3.6
VCC = 3.6 V
3.4
LVCMOS Output Swing − V
3.2
3.0
2.8
2.6
VCC = 3.3 V
2.4
VCC = 3 V
2.2
2.0
1.8
TA = 25°C
Load = 5 pF (See Figure 12)
1.6
1.4
50
100
150
200
250
300
350
400
450
500
f − Frequency − MHz
G006
Figure 6.
LVCMOS OUTPUT SWING
vs
FREQUENCY
3.6
3.4
VCC = 3.6 V
LVCMOS Output Swing − V
3.2
3.0
2.8
2.6
2.4
VCC = 3.3 V
2.2
VCC = 3 V
2.0
1.8
TA = 25°C
Load = 10 pF (See Figure 12)
1.6
1.4
50
100
150
200
250
300
350
400
450
500
f − Frequency − MHz
G007
Figure 7.
12
CDCM7005
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SCAS793A – JUNE 2005 – REVISED JUNE 2005
TYPICAL CHARACTERISTICS (continued)
OUTPUT REFERENCE VOLTAGE (VBB)
vs
LOAD
4.0
VCC = 3.3 V
TA = 25°C
VBB − Output Reference Voltage − V
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0.0
−5
0
5
10
15
20
25
30
35
I − Load − mA
G008
Figure 8.
PARAMETER MEASUREMENT INFORMATION
Yx
VOH
VOD
Yx
VOL
80%
20%
0V
tr
VOUTpp
tf
T0058-01
Figure 9. LVPECL Differential Output Voltage and Rise/Fall Time
13
CDCM7005
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SCAS793A – JUNE 2005 – REVISED JUNE 2005
PARAMETER MEASUREMENT INFORMATION (continued)
LVPECL
VCXO_IN
/VCXO_IN
tpd(LH) / tpd(HL); tsk(p) = | tpd(HL) − tpd(LH) |
YxA
LVPECL
YxB
YxA
LVPECL
YxB
tsk(o)LVPECL
YxA
LVPECL
YxB
YxA
LVCMOS
tsk p_c
LVCMOS
VCXO_IN
/VCXO_IN
tpd(LH); tsk(p) = | tpd(HL) − tpd(LH) |
YxA/B
LVCMOS
tsk(o)LVCMOS
YxA/B
LVCMOS
A.
Output skew, tsk(o), is calculated as the greater of:
The difference between the fastest and the slowest tpd(LH)n (n = 0...4)
The difference between the fastest and the slowest tpd(HL)n (n = 0...4)
B.
Pluse skew, tsk(p), is calculated as the magnitude of the absolute time difference between the high-to-low (tpd(HL)) and
the low-to-high (tpd(LH)) propagation delays when a single switching input causes one or more outputs to switch,
tsk(p) = |tpd(HL) – tpd(LH) |. Pulse skew is sometimes refered to as pulse width distortion or duty cycle skew.
Figure 10. Output Skew
14
CDCM7005
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SCAS793A – JUNE 2005 – REVISED JUNE 2005
PARAMETER MEASUREMENT INFORMATION (continued)
VIH
50% VCC
VIL
REF_IN
tpho LVPECL
VOH
YxB
LVPECL
VOL
YxA
tpho LVCMOS
VOH
LVCMOS
VOL
T0060-01
Figure 11. Phase Offset
CDCM7005
1kW
LVCMOS
Y3
1kW
10pF
S0079-01
Figure 12. LVCMOS Output Loading During Device Test
15
CDCM7005
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SCAS793A – JUNE 2005 – REVISED JUNE 2005
PARAMETER MEASUREMENT INFORMATION (continued)
VCC
ZO = 50W
Yx
CDCM7005
Driver
LVPECL
Receiver
ZO = 50W
Yx
50W
50W
VEE
VT = VCC – 2V
S0078-01
Figure 13. LVPECL Output Loading During Device Test
SPI CONTROL INTERFACE
The serial interface of the CDCM7005 is a simple SPI-compatible interface for writing to the registers of the
device and consists of three control lines: CTRL_CLK, CTRL_DATA, and CTRL_LE. There are four 32-bit wide
registers, which can be addressed by the two LSBs of a transferred word (bit 0 and bit 1). Every transmitted word
must have 32 bits, starting with MSB first. Each word can be written separately. Bit 7, 8, 10, and Bit 12 to 31 of
Word 3 are reserved for factory test purposes and must be filled with zeros. The transfer is initiated with the
falling edge of CTRL_LE; as long as CTRL_LE is high, no data can be transferred. During CTRL_LE, low data
can be written. The data has to be applied at CTRL_DATA and has to be stable before the rising edge of
CTRL_CLK. The transmission is finished by a rising edge of CTRL_LE. With the rising edge of CTRL_LE, the
new word is asynchronously transferred to the internal register (e.g., N, M, P, ...). Each word has to be
separately transmitted by this procedure.
16
CDCM7005
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SCAS793A – JUNE 2005 – REVISED JUNE 2005
PARAMETER MEASUREMENT INFORMATION (continued)
t4
t3
CTRL_CLK
th2
tsu1
CTRL_DATA
Bit31 (MSB)
Bit30
Bit2
Bit1
Bit0
t7
CTRL_LE
tsu5
tsu6
T0061-01
Figure 14. Timing Diagram SPI Control Interface
The SPI serial protocol accepts word Write operation only. There is neither a read, acknowledge, nor a
handshake operation.
The following four words include the register settings of the programmable functions of the CDCM7005. It can be
modified to the customer application by changing one or more bits. It comes up with a default register setting
after power up or if the power down (PD) control signal is applied. The default setting is shown in column five of
the following words.
A low active function is shown as [0] and a high active function is shown as [1].
17
CDCM7005
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SCAS793A – JUNE 2005 – REVISED JUNE 2005
PARAMETER MEASUREMENT INFORMATION (continued)
Word 0
BIT
(1)
18
BIT NAME
DESCRIPTION/FUNCTION
POWER UP
CONDITION
0
C0
Register Selection
0
1
C1
Register Selection
0
2
M0
Reference Divider M Bit 0
1
3
M1
Reference Divider M Bit 1
1
4
M2
Reference Divider M Bit 2
1
5
M3
Reference Divider M Bit 3
1
6
M4
Reference Divider M Bit 4
1
7
M5
Reference Divider M Bit 5
1
8
M6
Reference Divider M Bit 6
1
Reference Divider M
PIN AFFECTED
BGA
QFN
9
M7
Reference Divider M Bit 7
0
10
M8
Reference Divider M Bit 8
0
11
M9
Reference Divider M Bit 9
0
12
N0
VCXO Divider N Bit 0
1
13
N1
VCXO Divider N Bit 1
1
14
N2
VCXO Divider N Bit 2
1
15
N3
VCXO Divider N Bit 3
1
16
N4
VCXO Divider N Bit 4
1
17
N5
VCXO Divider N Bit 5
1
18
N6
VCXO Divider N Bit 6
1
19
N7
VCXO Divider N Bit 7
0
20
N8
VCXO Divider N Bit 8
0
21
N9
VCXO Divider N Bit 9
0
22
N10
VCXO Divider N Bit 10
0
23
N11
VCXO Divider N Bit 11
0
24
DLYM0
Reference Phase Delay M Bit 0
0
25
DLYM1
Reference Phase Delay M Bit 1
0
26
DLYM2
Reference Phase Delay M Bit 2
0
27
DLYN0
Feedback Phase Delay N Bit 0
0
28
DLYN1
Feedback Phase Delay N Bit 1
0
29
DLYN2
Feedback Phase Delay N Bit 2
0
30
MANAUT
Manual or Auto Ref.
Manual Reference Clock Selection [0]
Automatic Reference Clock Selection [1]
0
A1, B1
36, 37
31
REFDEC
Freq. Detect
Reference Frequency Detection on [0], off [1]
0
C8
23
VC(X)O Divider N
Progr. Delay M
Progr. Delay N
(1)
If set to low, STATUS_REF will be in normal operation. If set to high, STATUS_REF will be high, even if no valid clock is
detected (<2 MHz). This is useful for reference inputs frequencies less than 2 MHz where the frequency detection circuitry normally
resets the STATUS_REF signal to low.
CDCM7005
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SCAS793A – JUNE 2005 – REVISED JUNE 2005
Word 1
BIT
BIT NAME
DESCRIPTION/FUNCTION
POWER UP
CONDITION
PIN AFFECTED
BGA
QFN
1
F1, G1
46, 47
For Outputs Y1A, Y1B:
LVPECL = enabled [1]; LVCMOS = enabled [0];
1
H2, H3
3, 4
OUTSEL2
For Outputs Y2A, Y2B:
LVPECL = enabled [1]; LVCMOS = enabled [0];
1
H4, H5
7, 8
5
OUTSEL3
For Outputs Y3A, Y3B:
LVPECL = enabled [1]; LVCMOS = enabled [0];
1
H6, H7
11, 12
6
OUTSEL4
For Outputs Y4A, Y4B:
LVPECL = enabled [1]; LVCMOS = enabled [0];
1
G8, F8
16,17
7
OUT0A0
Output Y0A Mode Bit 0
0
F1
46
8
OUT0A1
Output Y0A Mode Bit 1
0
F1
46
0
C0
Register Selection
1
1
C1
2
OUTSEL0
Register Selection
0
For Output Y0A, Y0B:
LVPECL = enabled [1]; LVCMOS = enabled [0];
3
OUTSEL1
4
Output (Yx) Signaling Selection
Output Y0 Mode
9
OUT0B0
Output Y0B Mode Bit 0
0
G1
47
10
OUT0B1
Output Y0B Mode Bit 1
0
G1
47
11
OUT1A0
Output Y1A Mode Bit 0
0
H2
3
12
OUT1A1
Output Y1A Mode Bit 1
0
H2
3
13
OUT1B0
Output Y1B Mode Bit 0
0
H3
4
14
OUT1B1
Output Y1B Mode Bit 1
0
H3
4
15
OUT2A0
Output Y2A Mode Bit 0
0
H4
7
16
OUT2A1
Output Y2A Mode Bit 1
0
H4
7
17
OUT2B0
Output Y2B Mode Bit 0
0
H5
8
18
OUT2B1
Output Y2B Mode Bit 1
0
H5
8
19
OUT3A0
Output Y3A Mode Bit 0
0
H6
11
20
OUT3A1
Output Y3A Mode Bit 1
0
H6
11
21
OUT3B0
Output Y3B Mode Bit 0
0
H7
12
22
OUT3B1
Output Y3B Mode Bit 1
0
H7
12
23
OUT4A0
Output Y4A Mode Bit 0
0
G8
16
24
OUT4A1
Output Y4A Mode Bit 1
0
G8
16
25
OUT4B0
Output Y4B Mode Bit 0
0
F8
17
26
OUT4B1
Output Y4B Mode Bit 1
0
F8
17
27
SREF
Displays the status of the reference clock at the
STATUS_REF output [0]
0
C8
23
0
D8, A8
22, 25
Output Y1 Mode
Output Y2 Mode
Output Y3 Mode
Output Y4 Mode
Status Ref.
Displays the selected clock (high for PRI_REF and
low for SEC_REF clock) at the STATUS_REF
output [1]
28
(1)
SXOIREF
Status VCXO or
I_REF_CP
Selects STATUS_VCXO [0]
Selects I_REF_CP [1] which enable external reference resistor used for charge pump current and
analog PLL lock detect output current.
29
ADLOCK
Analog or Digital
Lock
Selects Digital PLL_LOCK [0]
Selects Analog PLL_LOCK [1]
0
A8
25
30
90DIV4
90 degree shift
div-4
90 degree output phase shift in div-4 mode on [1];
off [0] (1)
0
Yx
Yx
31
90DIV8
90 degree shift
div-8
90 degree output phase shift in div-8 mode on [1];
off [0] (1)
0
Yx
Yx
The P 16-Div has to be selected to obtain the 90 degree phase shift. If bit 30 or bit 31 is set, the Div-by-16 mode is no longer available.
The outputs are switched in pairs. Only one bit can be set at a time. If both bits set to [1] at the same time, no 90 degree phase shift
mode is selected (equal to off-mode setting).
19
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SCAS793A – JUNE 2005 – REVISED JUNE 2005
Word 2
BIT
BIT
NAME
DESCRIPTION/FUNCTION
POWER UP
CONDITION
PIN AFFECTED
BGA
QFN
0
C0
Register Selection
0
1
C1
Register Selection
1
2
CP_DIR
Determines in which direction CP current regulates (Reference
Clock leads to Feedback Clock – see Figure 23)
0
A4
31
Preset charge pump output voltage to VCC_CP/2, on [1], off [0]
0
A4
31
CP Current Setting Bit 0
0
A4
31
CP Direction
– positive CP output current [0];
– negative CP output current [1];
20
3
PRECP
4
CP0
5
CP1
CP Current Setting Bit 1
1
A4
31
6
CP2
CP Current Setting Bit 2
0
A4
31
7
CP3
CP Current Setting Bit 3
1
A4
31
8
PFD0
PFD Pulse
Width
PFD Pulse Width PFD Bit 0
0
A4
31
PFD Pulse Width PFD Bit 1
0
A4
31
FB_MUX
Feedback MUX Select Bit 0
1
CP Current
9
PFD1
10
FBMUX0
11
FBMUX1
Feedback MUX Select Bit 1
0
12
FBMUX2
Feedback MUX Select Bit 2
1
13
Y0MUX0
Output Y0x Select Bit 0
1
F1, G1
46, 47
14
Y0MUX1
Output Y0x Select Bit 1
0
F1, G1
46, 47
15
Y0MUX2
Output Y0x Select Bit 2
1
F1, G1
46, 47
16
Y1MUX0
Output Y1x Select Bit 0
1
H2, H3
3, 4
17
Y1MUX1
Output Y1x Select Bit 1
0
H2, H3
3, 4
18
Y1MUX2
Output Y1x Select Bit 2
1
H2, H3
3, 4
19
Y2MUX0
Output Y2x Select Bit 0
1
H4, H5
7, 8
20
Y2MUX1
Output Y2x Select Bit 1
0
H4, H5
7, 8
21
Y2MUX2
Output Y2x Select Bit 2
1
H4, H5
7, 8
22
Y3MUX0
Output Y3x Select Bit 0
1
H6, H7
11, 12
23
Y3MUX1
Output Y3x Select Bit 1
0
H6, H7
11, 12
24
Y3MUX2
Output Y3x Select Bit 2
1
H6, H7
11, 12
25
Y4MUX0
Output Y4x Select Bit 0
1
G8, F8
16, 17
26
Y4MUX1
Output Y4x Select Bit 1
0
G8, F8
16, 17
27
Y4MUX2
Output Y4x Select Bit 2
1
G8, F8
16, 17
28
PD
Power Down mode on [0], off [1]
1
Yx
Yx
29
RESHOL
RESET or HOLD Pin definition: RESET [0] or HOLD [1]
0
H8
14
30
RESET
Resets all dividers [0] - (equal to RESET pin function)
1
31
HOLD
3-state charge pump [0] - (equal to HOLD pin function)
1
A4
31
Y0_MUX
Y1_MUX
Y2_MUX
Y3_MUX
Y4_MUX
CDCM7005
www.ti.com
SCAS793A – JUNE 2005 – REVISED JUNE 2005
Word 3
BIT
BIT
NAME
DESCRIPTION/FUNCTION
0
1
Lock Window
(2)
PIN AFFECTED
BGA
QFN
1
A8
25
Lock-detect window Bit 1
0
A8
25
Number of coherent lock events Bit 0
0
A8
25
Number of coherent lock events Bit 1
1
A8
25
Cycle slip mode only for out-of-lock detection on [1] or
off [0] (1)
0
A8
25
Register selection
1
Register selection
1
Lock-detect window Bit 0
2
LOCKW 0
3
LOCKW 1
4
LOCKC0
5
LOCKC1
6
CSLIP
7
RES
RESERVED
0
RES
RES
8
RES
RESERVED
0
RES
RES
9
HOLDF
Enables the frequency hold-over function on [1], off [0]
0
RESERVED
0
RES
RES
HOLD function always activated [1]; (2)
Triggered by analog PLL lock detect outputs [0] (if
analog PLL Lock signal is set then HOLD is activated;
if analog PLL lock signal is reset then HOLD is
de-activated).
0
Lock Cycles
Cycle Slip
HOLD Function
10
(1)
POWER UP
CONDITION
11
HOLDTR
HOLD Trigger Condition
12
RES
RESERVED
0
RES
RES
13
RES
RESERVED
0
RES
RES
14
RES
RESERVED
0
RES
RES
15
RES
RESERVED
0
RES
RES
16
RES
RESERVED
0
RES
RES
17
RES
RESERVED
0
RES
RES
18
RES
RESERVED
0
RES
RES
19
RES
RESERVED
0
RES
RES
20
RES
RESERVED
0
RES
RES
21
RES
RESERVED
0
RES
RES
22
RES
RESERVED
0
RES
RES
23
RES
RESERVED
0
RES
RES
24
RES
RESERVED
0
RES
RES
25
RES
RESERVED
0
RES
RES
26
RES
RESERVED
0
RES
RES
27
RES
RESERVED
0
RES
RES
28
RES
RESERVED
0
RES
RES
29
RES
RESERVED
0
RES
RES
30
RES
RESERVED
0
RES
RES
31
RES
RESERVED
0
RES
RES
If Cycle Slip mode only for out-of-lock detection is on, the selected lock detect window is valid for lock detect. Independent from this, out
of lock is detected if a cycle slip occurs.
HOLD function always activated is recommended for test purposes only.
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CDCM7005
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SCAS793A – JUNE 2005 – REVISED JUNE 2005
FUNCTIONAL DESCRIPTION OF THE LOGIC
Reference Divider M (Word 0) (3)
M9
M8
M7
M6
M5
M4
M3
M2
M1
M0
Div by
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
1
2
0
0
0
0
0
0
0
0
1
0
3
0
0
0
0
0
0
0
0
1
1
4
1
1
1
1
128
Default
•
•
•
0
0
0
1
1
1
Yes
•
•
•
(3)
1
1
1
1
1
1
1
1
0
1
1022
1
1
1
1
1
1
1
1
1
0
1023
1
1
1
1
1
1
1
1
1
1
1024
If the divider value is Q, then the code will be the binary value of (Q–1).
VC(X)O Feedback Divider N (Word 0) (1)
N11
N10
N0
N8
N7
N6
N5
N4
N3
N2
N1
N0
Div by
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
1
0
1
2
0
0
0
0
0
0
0
0
1
0
1
0
3
0
0
0
0
0
0
0
0
1
1
1
1
4
1
1
1
1
1
128
Default
•
•
•
0
0
0
0
0
1
1
•
•
•
(1)
22
1
1
1
1
1
1
1
1
1
1
0
1
4094
1
1
1
1
1
1
1
1
1
1
1
0
4095
1
1
1
1
1
1
1
1
1
1
1
1
4096
If the divider value is Q, then the code will be the binary value of (Q–1).
Yes
CDCM7005
www.ti.com
SCAS793A – JUNE 2005 – REVISED JUNE 2005
Output Mode Selection for LVCMOS and LVPECL Outputs: Y0A, Y0B, Y1A …Y4B (Word 1) (1)
OUTSELx
OUTxB1
OUTxB0
LVCMOS
[YxB]
OUTxA1
OUTxA0
0
0
0
0
0
Active
0
0
Active
1
3-state
0
1
3-state
0
1
0
Inverting
1
0
Inverting
0
1
1
Low
1
1
Low
OUTSELx
OUTxB1
OUTxB0
OUTxA1
OUTxA0
LVCMOS
[YxA]
Default
1
x
x
x
0
Active
Yx
1
x
x
x
1
3-state
LVCMOS
LVPECL
(1)
LVCMOS
[YxA]
Default
If the differential LVPECL output e.g. Y0A:Y0B is selected (bit 2 of word 1), then only bit 7 of word 1 defines the output mode for
Y0A:Y0B. The settings of bit 8, bit 9, and bit 10 of word 1 are therefore not relevant to the Y0A:Y0B. This applies for the other LVPECL
outputs as well.
Reference Delay M (PRI_REF or SEC_REF) and Feedback Delay N (VCXO) Phase Adjustment (Word 0) (1)
(1)
DLYM2 / DLYN2
DLYM1 / DLYN1
DLYM0 / DLYN0
Phase Offset
Default
0
0
0
0 ps
Yes
0
0
1
±160 ps
0
1
0
±320 ps
0
1
1
±480 ps
1
0
0
±830 ps
1
0
1
±1130 ps
1
1
0
±1450 ps
1
1
1
±1750 ps
If Progr. Delay M is set, all Yx outputs are lagging to the reference clock according to the value set. If Progr. If Delay N is set; all Yx
outputs are leading to the reference clock according to the value set. Above are typical values at VCC = 3.3 V, Temp = 25°C,
PECL-output relate to Div4 mode.
PFD Pulse Width Delay (Word 2)
(1)
(2)
PFD1 (1)
PFD0 (1)
PFD Pulse Width (1) (2)
Default (1)
0
0
1.5 ns
Yes
0
1
3 ns
1
0
4.5 ns
1
1
6 ns
The PFD pulse width delay gets around the dead zone of the PFD transfer function and reduces phase noise and reference spurs.
Typical values at V = 3.3 VCC, Temp = 25°C .
Lock-Detect Window (Word 3)
(1)
(2)
LOCKW1
LOCKW0
Phase-Offset at PFD Input (1)
Default
0
0
3.5 ns
Yes
0
1
8.5 ns
1
0
18.5 ns
1
1
Cycle slip (2)
Typical Values at VCC = 3.3 V, Temp = 25°C.
Cycle slip occurs when the phase shift at the PFD is greater than one period of the frequency. It is a complete (integer number) cycle
jump, i.e., cause by a loss-of-lock of the PLL.
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CDCM7005
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SCAS793A – JUNE 2005 – REVISED JUNE 2005
Number of Successive Lock Events Inside the Lock Detect Window (Word 3)
(1)
LOCKC1 (1)
LOCKC0 (1)
No. of Successive Lock Events (1)
0
0
1
0
1
16
1
0
64
1
1
256
Default (1)
Yes
This does not apply to Out-of-Lock condition.
Charge Pump Current (Word 2)
CP3
CP2
CP1
CP0
Typical Charge Pump Current
0
0
0
0
0 µA (3-state)
0
0
0
1
200 µA
0
0
1
0
400 µA
0
0
1
1
600 µA
0
1
0
0
800 µA
0
1
0
1
1 mA
0
1
1
0
1.2 mA
0
1
1
1
1.4 mA
1
0
0
0
1.6 mA
1
0
0
1
1.8 mA
1
0
1
0
2.0 mA
1
0
1
1
2.2 mA
1
1
0
0
2.4 mA
1
1
0
1
2.6 mA
1
1
1
0
2.8 mA
1
1
1
1
3 mA
Default
Yes
FB_MUX Selection (Word 2)
FBMUX2
FBMUX1
FBMUX0
Selected VC(X)O Signal for the
Phase Discriminator
0
0
0
Div by 1
0
0
1
Div by 2
0
1
0
Div by 3
0
1
1
Div by 4
1
0
0
Div by 6
1
0
1
Div by 8
1
1
0
Div by 16 (1)
1
1
1
Div by 8
(1)
Default
Yes
This divider setting depends on the selected P-divider mode for the “Div-by-16” divider. In the default mode (after power up), Div-by-16
is selected. But if bit 30 or bit 31 of word 1 is set to [1], then the Div-by-4 and 90 degree phase shift or Div-by-8 and 90 degree phase
shift is selected.
Yx_MUX – Output Divider Selection for Y0, Y1, Y2, Y3, Y4 (Word 2)
24
YxMUX2
YxMUX1
YxMUX0
Selected Divided V(C)XO Signal for the
Yx Outputs
0
0
0
Div by 1
0
0
1
Div by 2
0
1
0
Div by 3
0
1
1
Div by 4
1
0
0
Div by 6
1
0
1
Div by 8
Default
all Yx
CDCM7005
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SCAS793A – JUNE 2005 – REVISED JUNE 2005
YxMUX2
YxMUX1
YxMUX0
Selected Divided V(C)XO Signal for the
Yx Outputs
1
1
0
Div by 16 (1)
1
1
1
Div by 8
(1)
Default
This divider setting depends on the selected P-divider mode for the “Div-by-16” divider. In the default mode (after power up), Div-by-16
is selected. But if bit 30 or bit 31 of word 1 is set to [1], then the Div-by-4 and 90 degree phase shift or Div-by-8 and 90 degree phase
shift is selected.
FEATURE DESCRIPTION
Automatic/Manual Reference Clock Switching
The CDCM7005 supports two reference clock inputs, the primary clock input, PRI_REF, and the secondary clock
input, SEC_REF. The clocks can be selected manually or automatically. The respective mode is selected by the
dedicated SPI register bit (Word 0, Bit 30).
In the manual mode, the external REF_SEL signal selects one of the two input clocks:
REF_SEL [1] -> primary clock is selected
REF_SEL [0] -> secondary clock is selected
In the automatic mode, the primary clock is selected by default even if both clocks are available. In case the
primary clock is not available or fails, then the input switches to the secondary clock as long until the primary
clock is back. Figure 15 shows the automatic clock selection.
1
PRI_REF
SEC_REF
1
2
3
4
2
Internal
Reference Clock
STATUS_REF
PRI_SEC_CLK
Primary Clock
Secondary Clock
Primary Clock
T0062-01
NOTE: PRI_REF is the preferred clock input.
Figure 15. Behavior of STATUS_REF and PRI_SEC_CLK
In the automatic mode, the frequencies of both clock signals have to be similar, but may differ by up to 20%. The
phase of the clock signal can be any.
The clock input circuitry is design to suppress glitches during switching between the primary and secondary clock
in the manual and automatic mode. This avoids an undefined switching of the following circuitries.
The phase of the output clock slowly follows the new input phase. There will be no phase-jump at the output.
How quick the phase adjustment is done depends on the selected loop parameter, i.e., at a loop bandwidth of
<100 Hz; the phase adjustment can take several ms. There is no phase build-out function supported (like in
SONET/SDH applications).
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CDCM7005
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SCAS793A – JUNE 2005 – REVISED JUNE 2005
1
PRI_REF
1
SEC_REF
2
3
4
2
Internal
Reference Clock
PRI_SEC_CLK
Secondary Clock
Primary Clock
Primary Clock
Yx Output
T0063-01
Figure 16. Phase Approach of Output to New Reference Clock
PLL Lock for Analog and Digital Detect
The CDCM7005 supports two PLL lock indications: the digital lock signal or the analog lock signal. Both signals
indicate logic high-level at PLL_LOCK if the PLL locks according the selected lock condition.
PLL Lock/Out-of-Lock Definition
The PLL is locked (set high), if the rising edge of the Reference Clock (PRI_REF or SEC_REF clock) and
Feedback Clock (VCXO_IN clock) at the PFD (phase frequency detect) are inside a predefined lock detect
window, or if no cycle-slip appears, for a pre-defined number of successive clock cycles.
The PLL is out-of-lock (set low), if the rising edge of the Reference Clock (PRI_REF or SEC_REF clock) and
Feedback Clock (VCXO_IN clock) at the PFD are outside the predefined lock detect window or if a cycle-slip
appears.
Both, the lock detect window and the number of successive clock cycles are user definable (Word 3, Bit 2-6).
Selected REF at PFD
(clock fed through M Divider and M Delay)
t(lockdetect)
VCXO_IN at PFD
(clock fed through N Divider and N Delay)
T0064-01
Figure 17. Lock Detect Window
The lock detect window describes the maximum allowed time difference for lock detect between the rising edge
of PRI_REF or SEC_REF and VCXO_IN. The time difference is detected at the phase frequency detector. The
rising edge of PRI_REF or SEC_REF is taken as reference. The rising edge of VCXO_IN is outside the lock
detect window if there is a phase displacement of more than +0.5 × t(lockdetect) or -0.5 x t(lockdetect).
Digital vs Analog Lock
Figure 18 and Figure 19 show the circuit for the digital and analog lock. The analog lock operates with an
external load capacitor.
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CDCM7005
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SCAS793A – JUNE 2005 – REVISED JUNE 2005
When selecting the digital PLL lock option, PLL_LOCK will possibly jitter several times between lock and out of
lock until a stable lock is detected. A single low-to-high step can be reached with a wide lock detect window and
high number of successive clock cycles. PLL_LOCK returns to out of lock if just one cycle is outside the lock
detect window or a cycle slip occurs.
VOut
CDCM7005
Power_Down
PLL_LOCK
Output
Lock_Out
Digital Lock Detection
Lock
80kW
5pF
Out-of-Lock
t
Lock_In
Vhigh = 0.55 VCC
Vlow = 0.35 VCC
S0080-01
Figure 18. Digital Lock-Detect
When selecting the analog PLL Lock option, the high-pulses load the external capacitor via the internal 110-µA
current source until logic high-level is reached. Therefore, more time is needed to detect logic high level, but
jittering of PLL_LOCK will be suppressed in case of digital lock. The time PLL_LOCK needs to return to out of
lock depends on the level of VOut, when the current source starts to unload the external capacitor.
VCC
100mA
(Lock)
Out-of-Lock
PLL_LOCK
Output
Power_Down
CDCM7005
Lock
VOut
Lock_Out
80kW
100mA
(Out-of-Lock)
C
5pF
VOut = 1/C ´ I ´ t
t
Lock_In
Vhigh = 0.55 VCC
Example:
for I = 110mA, C = 10nF, VCC = 3.3 V,
and Vhigh = Vout = 0.55 ´ Vcc = 1.8V
³ t = 164ms
Vlow = 0.35 VCC
S0081-01
Figure 19. Analog Lock-Detect
Differential LVPECL Outputs and Single-Ended LVCMOS Outputs
The CDCM7005 supports up to 5 × LVPECL outputs or 10 × LVCMOS/LVTTL outputs or any combination of
these. The single-ended LVCMOS outputs are arranged in pairs which mean both outputs of a LVCMOS pair
have the same frequency but can separately be disabled or inverted. The power up output arrangement is five
LVPECL (default setting).
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CDCM7005
www.ti.com
SCAS793A – JUNE 2005 – REVISED JUNE 2005
The LVPECL outputs are designed to terminate in to a 50-Ω load to VCC– 2 V. The LVCMOS outputs supports
the standard LVCMOS load (see Figure 12). The LVPECL and LVCMOS outputs can be enabled (normal
operation) or disabled (3-state).
In addition, the output phase can be shifted by 90 degrees when using the additional div-by-4 or div-by-8 mode
of the P16-Div (see Figure 20). In the default mode (after power up), the div-by-16 mode of the P16-Div is active.
To change it to a 90 degree phase shift, bit 30 or bit 31 of word 1 has to be programmed accordingly. The P
16-Div has to be selected via the dedicated YxMUX to obtain the 90 degree phase shift. The outputs are
switched in pairs. When selecting the 90 degree phase shift mode, the div-by-16 functions will no longer be
available. The 90 degree phase shifted signal is lagging to the non-shifted signal.
÷1
÷2
÷3
÷4
VCXO_IN
VCXO_IN
PECL
Input
÷6
÷ /88
÷4
90o
÷8
90o
÷ 16
P16-Div
P Divider
B0058-01
Figure 20. 90 Degree Phase Shift Option of P-Divider
The following diagram shows the LVCMOS and LVPECL output signal when 90 degree phase shift is on.
Reference Clock
VCXO Clock
Y-Output div4
90 deg
90 deg
Y-Output div4
(90 deg shift)
Y-Output div8
90 deg
90 deg
Y-Output div8
(90 deg shift)
LVCMOS Outputs
LVPECL Outputs
T0065-01
Figure 21. Output Switching Diagram
In addition, the LVCMOS supports disabled-to-low and 180 degree output phase shift for each output individually.
When selecting the 180 degree phase shift together with the 90 degree phase shift, the respective outputs has a
total phase shift of 270 degree (see Table 2).
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CDCM7005
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SCAS793A – JUNE 2005 – REVISED JUNE 2005
Table 2. LVCMOS Phase Shift Options
Phase
P-Divider
180°Phase-Shift
P16-Div - Function
0°
Any P-Divider
No
div-by-16
90°
P16-Div
No
div-by-4 or div-by-8
180°
Any P-Divider
Yes
div-by-16
270°
P16-Div
Yes
div-by-4 or div-by-8
If the P16-Div is selected by the FB_MUX and div-by-4 or div-by-8 is active, the 90 degree phase shifted clock
will be synchronized to PRI_REF or SEC_REF. This means all outputs Yxx, which are switched to div-by-4 or
div-by-8, are in phase to PRI_REF or SEC_REF. All other outputs are 90 degree phase shifted with leading
phase.
Frequency Hold-Over Mode
The HOLD function is a useful feature which helps the designer to improve the system reliability. The HOLD
function holds the output frequency in case the input reference clock fails or is disrupted. During HOLD, the
charge pump is switched off (3-state) freezing the last valid output frequency. The hold function will be released
after a valid reference clock is back. For proper HOLD function, the analog PLL lock detect mode has to be
active.
The following register settings are involved with the HOLD function:
• Lock Detect Window (Word 3, Bit 2, 3, 6): Defines the window in ns inside the lock is valid. The size is
3.5 ns, 8.5 ns, 18.5 ns, or a complete cycle-slip. Lock is set if reference clock and the feedback clock are
inside this predefined lock-detect window for a pre-selected number of successive cycles or if a cycle-slip no
longer occurs.
• Out-of-Lock: Defines the out-of-lock condition: If the reference clock and the feedback clock at the PFD are
outside the predefined Lock Detect Window or if a cycle-slip occurs.
• Cycle-Slip (Word 3, Bit 6): Cycle-slip occurs when the phase shift at the PFD is greater than one period of
the frequency. It is a complete (integer number) cycle jump, i.e. caused by an out-of-lock of the PLL.
Cycle-slip is equivalent to the PLL pull-in time.
• Number of Clock Cycles (Word 3, Bit 4, 5): Defines the number of successive PFD cycles which have to
occur inside the lock window to set Lock detect. This applies not for out-of-lock condition.
• Hold-Function (Word 3, Bit 9): Selects HOLD function (see more details below).
• Hold-Trigger (Word 3, Bit 11): Defines whether the HOLD function is always activated (Bit 11 = [1]) or
whether it is dependent on the state of the analog PLL lock detect output (Bit 11 = [0]). In the latter case,
HOLD is activated, if lock is set (high) and de-activated if Lock is reset (low).
• Analog PLL Lock Detect (Word 1, Bit 29): Analog lock output charges or discharges an external capacitor
with every valid lock cycle. The time constant for Lock detect can be set by the value of the capacitor.
The CDCM7005 supports two types of HOLD functions, one external controllable HOLD mode and one internal
mode, HOLD.
With the external HOLD function the charge pump can directly be switched into 3-state (pin H8 [BGA] or pin 14
[QFN] can be programmed for HOLD [Word 2, Bit 29]). This function is also available via SPI register (Word 2,
Bit 31).
If logic low is applied to the HOLD pin, the charge pump will be switched to 3-state. After the HOLD pin is
released, the charge pump is switched back in to normal operation with the next valid reference clock cycle at
PRI_REF or SEC_REF and the next valid feedback clock cycle at the PFD. During HOLD, the P divider and all
outputs Yx are at normal operation.
HOLD-Over-Function: The PLL has to be in lock to start the HOLD function. It switches the charge pump in to
3-State when an out-of-lock event occurs. It leaves the 3-state charge pump state when the reference clock is
back. Then it starts a locking sequence of 64 cycles before it goes back to the beginning of the HOLD-over loop.
The dedicated looking sequence and a digital phase alignment enable a fast lock.
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CDCM7005
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SCAS793A – JUNE 2005 – REVISED JUNE 2005
Start
PLL
Out-of-Lock?
Frequency Hold-Over Function works in
combination with the Analog Lock-Detect
function only!
No
PLL is out-of-lock if the phase
difference of Reference Clock and
Feedback Clock at PFD are outside the
predefined Lock-Detect-Window or if a
Cycle-Slip occurs.
Yes
PLL-Lock
Output
Set?
No
(The ‘PLL-Lock Output Set?’ enquiry can be bypassed by
setting the HOLDTR bit to [1] (Word 3, Bit 11)
Yes
3-State Charge-Pump
Reference Clock
Back?
PLL has to be in LOCK to start
HOLD-Function.
(The Analog Lock output is not reset by the first Out-ofLock event. It stays ‘High’ depending on the analog time
delay (output C-load). The time delay must be long enough
to assure proper HOLD function)
Charge-Pump is switched into 3-State.
P-divider and Yx output are at normal operation.
No
The Charge-Pump remains in 3-State
until the Reference Clock is back. The 1st
valid Reference Clock at the PFD releases
the Charge-Pump.
Yes
64 PFD
Lock-Cycles
The PLL acquire 64 lock cycles to phase
align to the input clock.
F0004-01
Figure 22. Frequency HOLD-Over Function
Charge Pump Preset to VCC_CP/2
The preset charge pump to VCC_CP/2 is a useful feature to quickly set the center frequency of the VC(X)O after
powerup or reset. The adequate control voltage for the VC(X)O will be provided to the charge-pump output by an
internal voltage divider of 1 kΩ/1 kΩ to VCC_CP and GND (VCC_CP/2).
This feature helps to get the initial frequency accuracy, i.e. required at CPRI (Common Public Radio Interface) or
OBSAI (Open Base Station Architecture Initiative).
The preset charge pump to VCC_CP/2 can be set and reset by SPI register (word 2, bit 3). This feature must be
disabled for PLL locking.
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CDCM7005
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Charge Pump Current Direction
The direction of the charge pump (CP) current pulse can be changed by the SPI register (word 2, bit 2). It
determines in which direction the CP current regulates (reference clock leads to feedback clock). Most
applications use the positive CP output current (power-up condition) because of the use of a passive loop filter.
The negative CP current is useful when using an active loop filter concept with inverting operational amplifier.
Figure 23 shows the internal PFD signal and the corresponding CP current.
PRI_REF or SEC_REF
Clock Fed Through the
M Divider and Delay
VCXO_IN Clock Fed Through
the N Divider and Delay
V(PFD1) (Internal Signal)
0V
PFD Pulse
Width Delay
PFD Pulse
Width Delay
V(PFD2) (Internal Signal)
VCC
CP_DIR (Bit 2 of Word 2 = 0,
Default State)
CP_DIR (Bit 2 of Word 2 = 1)
T0076-01
NOTE: The purpose of the PFD pluse width delay is to improve spurious suppression.
Figure 23. Charge Pump Current Direction (VCXO and VCO Support)
31
CDCM7005
www.ti.com
SCAS793A – JUNE 2005 – REVISED JUNE 2005
APPLICATION INFORMATION
Phase Noise Reference Circuit
Phase Noise Reference Circuit (See the EVM)
VCXO
Low-Pass Filter
245.76MHz
Gain = 21.3kHz/V
R2
160W
V_CTRL
PECL_OUT_B
PECL_OUT
C3
100nF
CDCM7005
PRI_REF
R1
4.7kW
CTRL_LE
CTRL_DATA
CTRL_CLK
SPI
VOC
R
130W
VOC
R
130W
C2
100nF
CP_OUT
C1
22mF
PLL_LOCK
Measurement
Equipment
STATUS_REF
10nF
STATUS_VCXO
VCXO_IN
YnA
VCXO_IN
YnB
10nF
R
82W
R
82W
R
150W
R
150W
R
50W
R
50W
S0082-01
Figure 24. Typical Applications Diagram With Passive Loop Filter
32
CDCM7005
www.ti.com
SCAS793A – JUNE 2005 – REVISED JUNE 2005
APPLICATION INFORMATION (continued)
Phase Noise Performance
PARAMETER (1)
REF_IN PHASE
NOISE
AT 30.72 MHz
TEST CONDITIONS
VCXO PHASE
NOISE
AT 245.76 MHz
Yx PHASE NOISE
AT 30.72 MHz
LVCMOS LVPECL
TYP (2)
TYP (2)
UNIT
phn10
Phase noise at 10 Hz
–109
–75
–104
–100
dBc/Hz
phn100
Phase noise at 100 Hz
–125
–97
–116
–116
dBc/Hz
phn1k
Phase noise at 1 kHz
–134
–117
–140
–140
dBc/Hz
phn10k
Phase noise at 10 kHz
–136
–138
–153
–152
dBc/Hz
phn100k
Phase noise at 100 kHz
–138
–148
–156
–153
dBc/Hz
phn1Mk
Phase noise at 1 MHz
–144
–148
–156
–153
dBc/Hz
phn10M
Phase noise at 10 MHz
–144
–148
–156
–153
dBc/Hz
Y = 30.72 MHz; fPFD = 200
kHz, Loop BW = 20 Hz,
Feedback Divider = 8 x 128
(N x P), fREF_IN = 30.72 MHz,
M-Divider = 128, ICP = 2 mA
PLL Stabilization Time
tstabi
(2)
(3)
Y = 30.72 MHz, fPFD = 200
kHz, Loop BW = 20 Hz,
Feedback Divider = 8 x 128
(N x P), fREF_IN = 30.72 MHz,
M-Divider = 128, ICP = 2 mA
400
ms
Output phase noise is dependent on the noise of the REF_IN clock and VCXO clock noise floor. The phase noise performance of the
BGA and the QFN package is equal. The phase noise measurements were taken with the CDCM7005 EVM and CDCM7005 SPI default
settings.
The typical stabilization time is based on the above application example. The stabilization criterion was a stable high level of
PLL_LOCK.
For further explanations, as well as phase noise/jitter test results using various VCXOs, see application note SCAA067.
−70
Ref_Clk
−80
VCXO
−90
LPF
CDCM7005
Phase-Noise
Analyzer
E5052A
VXCO
245.76MHz (581fs)
−100
L(f) − dB
(1)
PLL stabilization time (3)
CDCM7005 in PLL−Closed Loop
CDCM7005 EVM
REF_IN: AgilentE8257C−61.44MHz
VCXO: Toyocom TCO−2111 245.76MHz
CDCM7005 Out is Y0A: 61.44MHz
Loop bandwidth ~ 30Hz
Date: 30. Mar 2005
−110
Phase Jitter (rms) − 1kHz − 10MHz
−120
−140
LVCMOS
61.44MHz
(230fs)
LVPECL
61.44MHz (282fs)
−130
Input−Clk
61.44MHz (769fs)
−150
−160
10
100
1k
10k
100k
1M
10M
f − Frequency − Hz
G009
Figure 25. Phase Noise (61.44-MHz REF_IN and 61.44-MHz Output Frequency)
33
CDCM7005
www.ti.com
SCAS793A – JUNE 2005 – REVISED JUNE 2005
In-Band Noise Performance
PARAMETER
TEST CONDITIONS
pnin-band In-band phase noise test conditions
pnf400
Phase noise floor at 400 kHz fPFD, in-band
noise – 20log(feedback div) (1)
pnf1
Phase noise floor at 1 Hz fPFD, in-band
noise – 20log(feedback div) – 10log(fPFD) (2)
(1)
(2)
MIN
Y = 900 MHz, fPFD = 400 kHz, Loop
BW = 27 kHz, Feedback Divider = 8 x 282
(N x P), fREF_IN = 10 MHz; M-Divider = 25, ICP =
3 mA
TYP
MAX
UNIT
–95
dBc/Hz
–162
dBc/Hz
–218
dBc/Hz
The synthesizer phase noise floor can be estimated by measuring the in-band noise at the output of the CDCM7005 and subtracting
20log(Feedback Divider) N (in case of CDCM7005 it is the N+P divider). The calculated phase noise floor still based on the PFD update
frequency, in the above specification, is 400 kHz.
The in-band noise can also be normalized to a comparison frequency of 1 Hz. The resulting phase noise floor is: pnfloor = PNmeasured
- 20log(N+P) - 10log(fPFD)
where:
pnNfloor = normalized phase noise floor in dBc/Hz
PNmeasured = in-band phase noise measurement in dBc/Hz
20log(N+P) = divider ratio of feedback loop
10log(fPFD) = PFD update frequency in Hz
APPLICATION INFORMATION ON THE CLOCK GENERATION FOR INTERPOLATING DACS
WITH THE CDCM7005
The CDCM7005, with its specified phase noise performance, is an ideal sampling clock generator for high speed
ADCs and DACs. The CDCM7005 is especially of interest for the new high speed DACs, which have integrated
interpolation filter. Such DACs achieve sampling rates up to 500 MSPS. This high data rate can typically not be
supported from the digital side driving the DAC (e.g., DUC, digital up-converter). Therefore, one approach to
interface the DUC to the DAC is the integration of an interpolation filter within the DAC to reduce the data rate at
the digital input of the DAC. In 3G systems, for example, a common sampling rate of a high speed DAC is
491.52 MSPS. With a four times interpolation of the digital data, the required input data rate results into
122.88 MSPS, which can be supported easily from the digital side. The DUC GC5016, which supports up to four
WCDMA carriers, provides a maximum output data rate of 150 MSPS. An example is shown in Figure 26, where
the CDCM7005 supplies the clock signal for the DUC/DDC and ADC/DAC.
GC5016
RF
To
BB
I
ADS5423
DDC
THS4509
LNA
14-Bit
ADC
Duplexer
IF1
Q
TRF3750
(PLL)
61.44MHz
3.84 MHz
LO1
CDCM7005
VCXO
491.52 MHz
122.88 MHz
From
BB
I
122.88 MHz
FIR
FIR
491.52 MHz
16-Bit
DAC
PA
DUC
FIR
Q
FIR
S
16-Bit
DAC
0
GC5016
DAC5687
90
TRF3702
LO1
(PLL)
B0064-01
Figure 26. CDCM7005 as a Clock Generator for High Speed ADCs and DACs
34
CDCM7005
www.ti.com
SCAS793A – JUNE 2005 – REVISED JUNE 2005
The generation of the two required clock signals (data input clock, clock for DAC) for such an interpolating DAC
can be done in different ways. The recommended way is to use the CDCM7005, which generates the fast
sampling clock for the DAC from the data input clock signal. The DAC5687 demands that the edges of the two
input clocks must be phase aligned within ±500 ps for latching the data properly. This phase alignment is well
achieved with the CDCM7005, which assures a maximum skew of 70 ps of the different different outputs to each
other.
AC-Coupled Interface to ADC/DAC
Another advantage of this clock solution is that the ADC or DAC can be driven directly in an ac-coupling interface
as shown in Figure 27, with an external termination in a differential configuration. There is no need for a
transformer to generate a differential signal from a single-ended clock source.
83 VCC
CDCM7005
LVPECL
Driver
130 150 YxA
VCC
83 DAC
130 150 YxB
Figure 27. Driving DAC or ADC With PECL Output of the CDCM7005
35
PACKAGE OPTION ADDENDUM
www.ti.com
5-Jul-2005
PACKAGING INFORMATION
Orderable Device
Status (1)
Package
Type
Package
Drawing
Pins Package Eco Plan (2)
Qty
CDCM7005RGZR
ACTIVE
QFN
RGZ
48
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-3-260C-168 HR
CDCM7005RGZT
ACTIVE
QFN
RGZ
48
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-3-260C-168 HR
CDCM7005ZVA
ACTIVE
BGA
ZVA
64
348
Pb-Free
(RoHS)
SNAGCU
Level-3-260C-168 HR
CDCM7005ZVAR
ACTIVE
BGA
ZVA
64
1000
Pb-Free
(RoHS)
SNAGCU
Level-3-260C-168 HR
CDCM7005ZVAT
ACTIVE
BGA
ZVA
64
250
Pb-Free
(RoHS)
SNAGCU
Level-3-260C-168 HR
Lead/Ball Finish
MSL Peak Temp (3)
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in
a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS) or Green (RoHS & no Sb/Br) - please check
http://www.ti.com/productcontent for the latest availability information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements
for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered
at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame
retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material)
(3)
MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder
temperature.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is
provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the
accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and continues to take
reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on
incoming materials and chemicals. TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited
information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI
to Customer on an annual basis.
Addendum-Page 1
MECHANICAL DATA
MPBG281 – MAY 2002
ZVA (S–PBGA–N64)
PLASTIC BALL GRID ARRAY
8,10
SQ
7,90
5,60 TYP
0,80
0,40
H
G
0,80
F
E
D
C
0,40
B
A1 Corner
A
1
2
3
4
5
6
7
8
Bottom View
0,75
0,65
1,40 MAX
Seating Plane
0,53
0,43
0,08
0,41
0,31
0,12
4204388/A 04/02
NOTES: A. All linear dimensions are in millimeters.
B. This drawing is subject to change without notice.
C. Mico Star BGA configuration.
D. This package is lead–free.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
1
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