Cirrus CS2200P-CZZR Fractional-n frequency synthesizer Datasheet

CS2200-OTP
Fractional-N Frequency Synthesizer
Features
General Description
 Delta-Sigma Fractional-N Frequency Synthesis
–
Generates a Low Jitter 6 - 75 MHz Clock
Relative to 8 - 75 MHz Reference Clock
 Highly Accurate PLL Multiplication Factor
–
Maximum Error Less Than 1 PPM
 One-Time Programmability
–
Configurable Hardware Control Pins
–
Configurable Auxiliary Output
 Flexible Sourcing of Reference Clock
–
External Oscillator or Clock Source
–
Supports Inexpensive Local Crystal
 Minimal Board Space Required
–
No External Analog Loop-filter
Components
The CS2200-OTP is an extremely versatile system
clocking device that utilizes a programmable phase lock
loop. The CS2200-OTP is based on an analog PLL architecture comprised of a Delta-Sigma Fractional-N
Frequency Synthesizer. This architecture allows for frequency synthesis and clock generation from a stable
reference clock. The CS2200-OTP has many configuration options which are set once prior to runtime. At
runtime there are three hardware configuration pins
available for mode and feature selection.
The CS2200-OTP is available in a 10-pin MSOP package in Commercial (-10°C to +70°C) grade. Customer
development kits are also available for custom device
prototyping, small production programming, and device
evaluation. Please see “Ordering Information” on
page 22 for complete details.
3.3 V
Timing Reference
Hardware Control
PLL Output
Hardware Configuration
PLL Lock Indicator
8 MHz to 75 MHz
Low-Jitter Timing
Reference
Phase
Comparator
Internal
Loop Filter
Voltage Controlled
Oscillator
Auxiliary
Output
6 to 75 MHz
PLL Output
Fractional-N
Divider
Delta-Sigma
Modulator
N
Output to Input
Clock Ratio
Preliminary Product Information
http://www.cirrus.com
This document contains information for a new product.
Cirrus Logic reserves the right to modify this product without notice.
Copyright © Cirrus Logic, Inc. 2008
(All Rights Reserved)
JUN '08
DS842PP1
CS2200-OTP
TABLE OF CONTENTS
1. PIN DESCRIPTION ................................................................................................................................. 4
2. TYPICAL CONNECTION DIAGRAM ..................................................................................................... 5
3. CHARACTERISTICS AND SPECIFICATIONS ...................................................................................... 6
RECOMMENDED OPERATING CONDITIONS .................................................................................... 6
ABSOLUTE MAXIMUM RATINGS ........................................................................................................ 6
DC ELECTRICAL CHARACTERISTICS ................................................................................................ 6
AC ELECTRICAL CHARACTERISTICS ................................................................................................ 7
4. ARCHITECTURE OVERVIEW ............................................................................................................... 8
4.1 Delta-Sigma Fractional-N Frequency Synthesizer ........................................................................... 8
5. APPLICATIONS ..................................................................................................................................... 9
5.1 One Time Programmability .............................................................................................................. 9
5.2 Timing Reference Clock Input .......................................................................................................... 9
5.2.1 Internal Timing Reference Clock Divider ................................................................................. 9
5.2.2 Crystal Connections (XTI and XTO) ...................................................................................... 10
5.2.3 External Reference Clock (REF_CLK) .................................................................................. 10
5.3 Output to Input Frequency Ratio Configuration ............................................................................. 10
5.3.1 User Defined Ratio (RUD) ..................................................................................................... 10
5.3.2 Manual Ratio Modifier (R-Mod) ............................................................................................. 11
5.3.3 Effective Ratio (REFF) .......................................................................................................... 11
5.3.4 Ratio Configuration Summary ............................................................................................... 11
5.4 PLL Clock Output ........................................................................................................................... 12
5.5 Auxiliary Output .............................................................................................................................. 13
5.6 Mode Pin Functionality ................................................................................................................... 13
5.6.1 M1 and M0 Mode Pin Functionality ....................................................................................... 13
5.6.2 M2 Mode Pin Functionality .................................................................................................... 14
5.6.2.1 M2 Configured as Output Disable .............................................................................. 14
5.6.2.2 M2 Configured as R-Mod Enable .............................................................................. 14
5.6.2.3 M2 Configured as AuxOutSrc Override ..................................................................... 14
5.7 Clock Output Stability Considerations ............................................................................................ 15
5.7.1 Output Switching ................................................................................................................... 15
5.7.2 PLL Unlock Conditions .......................................................................................................... 15
6. PARAMETER DESCRIPTIONS ........................................................................................................... 16
6.1 Modal Configuration Sets ............................................................................................................... 16
6.1.1 R-Mod Selection (RModSel[1:0]) ........................................................................................... 16
6.1.2 Auxiliary Output Source Selection (AuxOutSrc[1:0]) ............................................................. 17
6.2 Ratio 0 - 3 ...................................................................................................................................... 17
6.3 Global Configuration Parameters ................................................................................................... 17
6.3.1 AUX PLL Lock Output Configuration (AuxLockCfg) .............................................................. 17
6.3.2 Reference Clock Input Divider (RefClkDiv[1:0]) .................................................................... 17
6.3.3 Enable PLL Clock Output on Unlock (ClkOutUnl) ................................................................. 18
6.3.4 M2 Pin Configuration (M2Config[2:0]) ................................................................................... 18
7. CALCULATING THE USER DEFINED RATIO .................................................................................... 19
7.1 12.20 Format .................................................................................................................................. 19
8. PROGRAMMING INFORMATION ........................................................................................................ 20
9. PACKAGE DIMENSIONS .................................................................................................................... 21
THERMAL CHARACTERISTICS ......................................................................................................... 21
10. ORDERING INFORMATION .............................................................................................................. 22
11. REVISION HISTORY .......................................................................................................................... 22
DS842PP1
2
CS2200-OTP
LIST OF FIGURES
Figure 1. Typical Connection Diagram ........................................................................................................ 5
Figure 2. Delta-Sigma Fractional-N Frequency Synthesizer ....................................................................... 8
Figure 3. Internal Timing Reference Clock Divider ..................................................................................... 9
Figure 4. External Component Requirements for Crystal Circuit .............................................................. 10
Figure 5. Ratio Feature Summary ............................................................................................................. 12
Figure 6. PLL Clock Output Options ......................................................................................................... 12
Figure 7. Auxiliary Output Selection .......................................................................................................... 13
Figure 8. M2 Mapping Options .................................................................................................................. 14
Figure 9. Parameter Configuration Sets .................................................................................................... 16
LIST OF TABLES
Table 1. Modal and Global Configuration .................................................................................................... 9
Table 2. Ratio Modifier .............................................................................................................................. 11
Table 3. Example 12.20 R-Values ............................................................................................................ 19
DS842PP1
3
CS2200-OTP
1. PIN DESCRIPTION
VD
1
10
M0
GND
2
9
M1
CLK_OUT
3
8
M2
AUX_OUT
4
7
XTI/REF_CLK
TST_IN
5
6
XTO
Pin Name
#
Pin Description
VD
1
Digital Power (Input) - Positive power supply for the digital and analog sections.
GND
2
Ground (Input) - Ground reference.
CLK_OUT
3
PLL Clock Output (Output) - PLL clock output.
AUX_OUT
4
Auxiliary Output (Output) - This pin outputs a buffered version of one of the input or output clocks,
or a status signal, depending on configuration.
TST_IN
5
XTO
XTI/REF_CLK
6
7
Test Input (Input) - This pin is for factory test purposes and must be connected to GND for proper
operation.
Crystal Connections (XTI/XTO) / Timing Reference Clock Input (REF_CLK) (Input/Output) XTI/XTO are I/O pins for an external crystal which may be used to generate the low-jitter PLL input
clock. REF_CLK is an input for an externally generated low-jitter reference clock.
M2
8
Mode Select (Input) - M2 is a configurable mode selection pin.
M1
9
Mode Select (Input) - M1 is a configurable mode selection pin.
M0
10 Mode Select (Input) - M0 is a configurable mode selection pin.
4
DS842PP1
CS2200-OTP
2. TYPICAL CONNECTION DIAGRAM
0.1 µF
1 µF
+3.3 V
VD
M2
System Microcontroller
M1
M0
CS2200-OTP
1
or
2
XTI/REF_CLK
To circuitry which requires
a low-jitter clock
AUX_OUT
To other circuitry or
Microcontroller
XTO
GND
Low-Jitter
Timing Reference
CLK_OUT
TST_IN
REF_CLK
1
N.C. x
XTO
or
Crystal
XTI
2
XTO
40 pF
40 pF
Figure 1. Typical Connection Diagram
DS842PP1
5
CS2200-OTP
3. CHARACTERISTICS AND SPECIFICATIONS
RECOMMENDED OPERATING CONDITIONS
GND = 0 V; all voltages with respect to ground. (Note 1)
Parameters
DC Power Supply
Symbol
Min
Typ
Max
Units
VD
3.1
3.3
3.5
V
TAC
-10
-
+70
°C
Ambient Operating Temperature (Power Applied)
Commercial Grade
Notes: 1. Device functional operation is guaranteed within these limits. Functionality is not guaranteed or implied
outside of these limits. Operation outside of these limits may adversely affect device reliability.
ABSOLUTE MAXIMUM RATINGS
GND = 0 V; all voltages with respect to ground.
Parameters
Symbol
Min
Max
Units
DC Power Supply
VD
-0.3
6.0
V
Input Current
IIN
-
±10
mA
Digital Input Voltage (Note 1)
VIN
-0.3
VD + 0.4
V
Ambient Operating Temperature (Power Applied)
TA
-55
125
°C
Storage Temperature
Tstg
-65
150
°C
WARNING: Operation at or beyond these limits may result in permanent damage to the device.
Notes: 1. The maximum over/under voltage is limited by the input current except on the power supply pin.
DC ELECTRICAL CHARACTERISTICS
Test Conditions (unless otherwise specified): VD = 3.1 V to 3.5 V; TA = -10°C to +70°C (Commercial Grade).
Parameters
Symbol
Min
Typ
Max
Units
Power Supply Current - Unloaded
(Note 2)
ID
-
12
18
mA
Power Dissipation - Unloaded
(Note 2)
PD
-
40
60
mW
Input Leakage Current
IIN
-
-
±10
µA
Input Capacitance
IC
-
8
-
pF
High-Level Input Voltage
VIH
70%
-
-
VD
Low-Level Input Voltage
VIL
-
-
30%
VD
High-Level Output Voltage (IOH = -1.2 mA)
VOH
80%
-
-
VD
Low-Level Output Voltage (IOH = 1.2 mA)
VOL
-
-
20%
VD
Notes: 2. To calculate the additional current consumption due to loading (per output pin), multiply clock output
frequency by load capacitance and power supply voltage.
For example, fCLK_OUT (49.152 MHz) * CL (15 pF) * VD (3.3 V) = 2.4 mA of additional current due to
these loading conditions on CLK_OUT.
6
DS842PP1
CS2200-OTP
AC ELECTRICAL CHARACTERISTICS
Test Conditions (unless otherwise specified): VD = 3.1 V to 3.5 V; TA = -10°C to +70°C (Commercial Grade);
CL = 15 pF.
Parameters
Crystal Frequency
Symbol
Conditions
Min
Typ
Max
Units
fXTAL
Fundamental Mode
8
-
50
MHz
Reference Clock Input Frequency
fREF_CLK
8
-
75
MHz
Reference Clock Input Duty Cycle
DREF_CLK
45
-
55
%
Internal System Clock Frequency
fSYS_CLK
8
18.75
MHz
PLL Clock Output Frequency
fCLK_OUT
6
75
MHz
-
PLL Clock Output Duty Cycle
tOD
Measured at VD/2
48
50
52
%
Clock Output Rise Time
tOR
20% to 80% of VD
-
1.7
3.0
ns
Clock Output Fall Time
tOF
80% to 20% of VD
-
1.7
3.0
ns
Period Jitter
tJIT
(Note 3)
-
70
150
ps rms
Base Band Jitter (100 Hz to 40 kHz)
(Notes 3, 4)
-
50
-
ps rms
Wide Band JItter (100 Hz Corner)
(Notes 3, 5)
-
175
-
ps rms
-
1
2
ms
0
-
±0.5
ppm
PLL Lock Time - REF_CLK
tLR
Output Frequency Synthesis Resolution (Note 6)
ferr
fREF_CLK = 8 to 75 MHz
Notes: 3. fCLK_OUT = 24.576 MHz; Sample size = 10,000 points; AuxOutSrc[1:0] = 11.
4. In accordance with AES-12id-2006 section 3.4.2. Measurements are Time Interval Error taken with 3rd
order 100 Hz to 40 kHz bandpass filter.
5. In accordance with AES-12id-2006 section 3.4.1. Measurements are Time Interval Error taken with 3rd
order 100 Hz Highpass filter.
6. The frequency accuracy of the PLL clock output is directly proportional to the frequency accuracy of the
reference clock.
DS842PP1
7
CS2200-OTP
4. ARCHITECTURE OVERVIEW
4.1
Delta-Sigma Fractional-N Frequency Synthesizer
The core of the CS2200 is a Delta-Sigma Fractional-N Frequency Synthesizer which has very high-resolution for Input/Output clock ratios, low phase noise, very wide range of output frequencies and the ability to
quickly tune to a new frequency. In very simplistic terms, the Fractional-N Frequency Synthesizer multiplies
the Timing Reference Clock by the value of N to generate the PLL output clock. The desired output to input
clock ratio is the value of N that is applied to the delta-sigma modulator (see Figure 2).
The analog PLL based frequency synthesizer uses a low-jitter timing reference clock as a time and phase
reference for the internal voltage controlled oscillator (VCO). The phase comparator compares the fractional-N divided clock with the original timing reference and generates a control signal. The control signal is filtered by the internal loop filter to generate the VCO’s control voltage which sets its output frequency. The
delta-sigma modulator modulates the loop integer divide ratio to get the desired fractional ratio between the
reference clock and the VCO output (thus the duty cycle of the modulator sets the fractional value). This
allows the design to be optimized for very fast lock times for a wide range of output frequencies without the
need for external filter components. As with any Fractional-N Frequency Synthesizer the timing reference
clock should be stable and jitter-free.
Timing Reference
Clock
Phase
Comparator
Internal
Loop Filter
Voltage Controlled
Oscillator
PLL Output
Fractional-N
Divider
Delta-Sigma
Modulator
N
Figure 2. Delta-Sigma Fractional-N Frequency Synthesizer
8
DS842PP1
CS2200-OTP
5. APPLICATIONS
5.1
One Time Programmability
The one time programmable (OTP) circuitry in the CS2200-OTP allows for pre-configuration of the device
prior to use in a system. There are two types of parameters that are used for device pre-configuration: modal
and global. The modal parameters are features which, when grouped together, create a modal configuration
set (see Figure 9 on page 16). Up to four modal configuration sets can be permanently stored and then dynamically selected using the M[1:0] mode select pins (see Table 1). The global parameters are the remaining configuration settings which do not change with the mode select pins. The modal and global parameters
can be pre-set at the factory or user programmed using the customer development kit, CDK2000; Please
see “Programming Information” on page 20 for more details.
Parameter Type
M[1:0] pins = 00
M[1:0] pins = 01
M[1:0] pins = 10
M[1:0] pins = 11
Modal
Configuration Set 0
Ratio 0
Configuration Set 1
Ratio 1
Configuration Set 2
Ratio 2
Configuration Set 3
Ratio 3
Global
Configuration settings set once for all modes.
Table 1. Modal and Global Configuration
5.2
Timing Reference Clock Input
The low jitter timing reference clock (RefClk) can be provided by either an external reference clock or an
external crystal in conjunction with the internal oscillator. In order to maintain a stable and low-jitter PLL output the timing reference clock must also be stable and low-jitter; the quality of the timing reference clock
directly affects the performance of the PLL and hence the quality of the PLL output.
5.2.1
Internal Timing Reference Clock Divider
The Internal Timing Reference Clock (SysClk) is limited to a lower maximum frequency than that allowed
on the XTI/REF_CLK pin. The CS2200-OTP supports the wider external frequency range by offering an
internal divider for RefClk. The RefClkDiv[1:0] global parameter should be configured such that SysClk,
the divided RefClk, then falls within the valid range as indicated in Figure 3.
Timing Reference Clock
XTI/REF_CLK
8 MHz < RefClk <
50 MHz (XTI)
75 MHz (REF_CLK)
Timing Reference
Clock Divider
÷1
÷2
÷4
Internal Timing
Reference Clock
8 MHz < SysClk < 18.75 MHz
RefClkDiv[1:0]
Fractional-N
Frequency
Synthesizer
PLL Output
N
Figure 3. Internal Timing Reference Clock Divider
It should be noted that the maximum allowable input frequency of the XTI/REF_CLK pin is dependent
upon its configuration as either a crystal connection or external clock input. See the “AC Electrical Characteristics” on page 7 for more details.
Referenced Control
Parameter Definition
RefClkDiv[1:0] .......................“Reference Clock Input Divider (RefClkDiv[1:0])” on page 17
DS842PP1
9
CS2200-OTP
5.2.2
Crystal Connections (XTI and XTO)
An external crystal may be used to generate RefClk. To accomplish this, a 20 pF fundamental mode parallel resonant crystal must be connected between the XTI and XTO pins as shown in Figure 4. As shown,
nothing other than the crystal and its load capacitors should be connected to XTI and XTO. Please refer
to the “AC Electrical Characteristics” on page 7 for the allowed crystal frequency range.
XTI
40 pF
XTO
40 pF
Figure 4. External Component Requirements for Crystal Circuit
5.2.3
External Reference Clock (REF_CLK)
For operation with an externally generated REF_CLK signal, XTI/REF_CLK should be connected to the
reference clock source and XTO should be left unconnected or terminated through a 47 kΩ resistor to
GND.
5.3
5.3.1
Output to Input Frequency Ratio Configuration
User Defined Ratio (RUD)
The User Defined Ratio, RUD, is a 32-bit un-signed fixed-point number which determines the basis for the
desired input to output clock ratio. Up to four different ratios, Ratio0-3, can be stored in the CS2200’s one
time programmable memory. Selection between the four ratios is achieved by the M[1:0] mode select
pins. The 32-bit RUD is represented in a 12.20 format where the 12 MSBs represent the integer binary
portion while the remaining 20 LSBs represent the fractional binary portion. The maximum multiplication
factor is approximately 4096 with a resolution of 0.954 PPM in this configuration. See “Calculating the
User Defined Ratio” on page 19 for more information.
The status of internal dividers, such as the internal timing reference clock divider, are automatically taken
into account. Therefore RUD is simply the desired ratio of the output to input clock frequencies.
Referenced Control
Parameter Definition
Ratio 0-3................................“Ratio 0 - 3” on page 17
M[1:0] ....................................“M1 and M0 Mode Pin Functionality” on page 13
10
DS842PP1
CS2200-OTP
5.3.2
Manual Ratio Modifier (R-Mod)
The manual Ratio Modifier is used to internally multiply/divide the currently addressed RUD (Ratio0-3
stored in the register space remain unchanged). The available options for R-Mod are summarized in
Table 2 on page 11. R-Mod is enabled via the M2 pin in conjunction with the appropriate setting of the
M2Config[2:0] global parameter (see Section 5.6.2 on page 14).
RModSel[1:0]
R Modifier
00
0.5
01
0.25
10
0.125
11
0.0625
Table 2. Ratio Modifier
Referenced Control
Parameter Definition
Ratio 0-3................................“Ratio 0 - 3” on page 17
RModSel[1:0] ........................“R-Mod Selection (RModSel[1:0])” section on page 16
M2Config[2:0]........................“M2 Pin Configuration (M2Config[2:0])” on page 18
5.3.3
Effective Ratio (REFF)
The Effective Ratio (REFF) is an internal calculation comprised of RUD and the appropriate modifiers, as
previously described. REFF is calculated as follows:
REFF = RUD • R-Mod
To simplify operation the device handles some of the ratio calculation functions automatically (such as
when the internal timing reference clock divider is set). For this reason, the Effective Ratio does not need
to be altered to account for internal dividers.
Ratio modifiers which would produce an overflow or truncation of REFF should not be used. In all cases,
the maximum and minimum allowable values for REFF are dictated by the frequency limits for both the
input and output clocks as shown in the “AC Electrical Characteristics” on page 7.
Selection of the user defined ratio from the four stored ratios is made by using the M[1:0] pins.
Referenced Control
Parameter Definition
M[1:0] pins.............................“M1 and M0 Mode Pin Functionality” on page 13
5.3.4
Ratio Configuration Summary
The RUD is the user defined ratio for which up to four different values (Ratio0-3) can be stored in the one
time programmable memory. The M[1:0] pins then select the user defined ratio to be used as well as the
modal configuration set. R-Mod is applied accordingly. The user defined ratio and ratio modifier make up
the effective ratio REFF, the final calculation used to determine the output to input clock ratio. The effective
ratio is then corrected for the internal dividers. The conceptual diagram in Figure 5 summarizes the fea-
DS842PP1
11
CS2200-OTP
tures involved in the calculation of the ratio values used to generate the fractional-N value which controls
the Frequency Synthesizer. The subscript ‘4’ indicates the modal parameters.
Timing Reference Clock
(XTI/REF_CLK)
Divide
RefClkDiv[1:0]
Effective Ratio REFF
M2 pin
M[1:0] pins
SysClk
User Defined Ratio RUD
RModSel[1:0]4
Ratio 0
RefClkDiv[1:0]
Ratio Format
Ratio 1
Ratio
Modifier
12.20
Ratio 2
Frequency
Synthesizer
PLL Output
Static Ratio, ‘N’
R Correction
Ratio 3
Figure 5. Ratio Feature Summary
Referenced Control
Parameter Definition
Ratio 0-3................................“Ratio 0 - 3” on page 17
M[1:0] pins.............................“M1 and M0 Mode Pin Functionality” on page 13
RModSel[1:0] ........................“R-Mod Selection (RModSel[1:0])” section on page 16
RefClkDiv[1:0] .......................“Reference Clock Input Divider (RefClkDiv[1:0])” on page 17
5.4
PLL Clock Output
The PLL clock output pin (CLK_OUT) provides a buffered version of the output of the frequency synthesizer.
The driver can be set to high-impedance with the M2 pin when the M2Config[1:0] global parameter is set to
either 000 or 010. The output from the PLL automatically drives a static low condition while the PLL is unlocked (when the clock may be unreliable). This feature can be disabled by setting the ClkOutUnl global
parameter, however the state CLK_OUT may then be unreliable during an unlock condition.
ClkOutUnl
PLL Locked/Unlocked
0
0
2:1 Mux
M2 pin with
M2Config[1:0] = 000, 010
0
1
2:1 Mux
PLL Output
PLL Clock Output
PLLClkOut
PLL Clock Output Pin
(CLK_OUT)
1
Figure 6. PLL Clock Output Options
Referenced Control
Parameter Definition
ClkOutUnl..............................“Enable PLL Clock Output on Unlock (ClkOutUnl)” on page 18
ClkOutDis ..............................“M2 Configured as Output Disable” on page 14
M2Config[2:0]........................“M2 Pin Configuration (M2Config[2:0])” on page 18
12
DS842PP1
CS2200-OTP
5.5
Auxiliary Output
The auxiliary output pin (AUX_OUT) can be mapped, as shown in Figure 7, to one of three signals: reference clock (RefClk), additional PLL clock output (CLK_OUT), or a PLL lock indicator (Lock). The mux is controlled via the AuxOutSrc[1:0] modal parameter. If AUX_OUT is set to Lock, the AuxLockCfg global
parameter is then used to control the output driver type and polarity of the LOCK signal (see section 6.3.1
on page 17). If AUX_OUT is set to CLK_OUT, the phase of the PLL Clock Output signal on AUX_OUT may
differ from the CLK_OUT pin. The driver for the pin can be set to high-impedance using the M2 pin when
the M2Config[1:0] global parameter is set to either 001 or 010.
AuxOutSrc[1:0]
Timing Reference Clock
(RefClk)
PLL Clock Output
(PLLClkOut)
AuxOutDis
Auxiliary Output Pin
(AUX_OUT)
3:1 Mux
PLL Lock/Unlock Indication
(Lock)
AuxLockCfg
Figure 7. Auxiliary Output Selection
Referenced Control
Parameter Definition
AuxOutSrc[1:0]......................“Auxiliary Output Source Selection (AuxOutSrc[1:0])” on page 17
AuxOutDis .............................“M2 Configured as Output Disable” on page 14
AuxLockCfg...........................“AUX PLL Lock Output Configuration (AuxLockCfg)” section on page 17
M2Config[2:0]........................“M2 Pin Configuration (M2Config[2:0])” on page 18
5.6
5.6.1
Mode Pin Functionality
M1 and M0 Mode Pin Functionality
M[1:0] determine the functional mode of the device and select both the default User Defined Ratio and
the set of modal parameters. The modal parameters are RModSel[1:0] and AuxOutSrc[1:0]. By modifying
one or more of the modal parameters between the 4 sets, different functional configurations can be
achieved. However, global parameters are fixed and the same value will be applied to each functional
configuration. Figure 9 on page 16 provides a summary of all parameters used by the device.
DS842PP1
13
CS2200-OTP
5.6.2
M2 Mode Pin Functionality
M2 usage is mapped to one of the optional special functions via the M2Config[2:0] global parameter. Depending on what M2 is mapped to, it will either act as an output enable/disable pin or override certain modal parameters. Figure 8 summarizes the available options and the following sections will describe each
option in more detail.
M2Config[2:0] global parameter
000
Disable CLK_OUT pin
001
Disable AUX_OUT pin
010
Disable CLK_OUT and AUX_OUT pins
011
RModSel[1:0] Modal Parameter Enable
100
Reserved
101
Reserved
110
Reserved
111
Force AuxOutSel[1:0] = 10 (PLL Clock Out)
M2 pin
Figure 8. M2 Mapping Options
5.6.2.1
M2 Configured as Output Disable
If M2Config[2:0] is set to either ‘000’, ‘001’, or ‘010’, M2 becomes an output disable pin for one or
both output pins. If M2 is driven ‘low’, the corresponding output(s) will be enabled, if M2 is driven
‘high’, the corresponding output(s) will be disabled.
5.6.2.2
M2 Configured as R-Mod Enable
If M2Config[2:0] is set to ‘011’, M2 becomes the R-Mod enable pin. It should be noted that M2 is
the only way to enable R-Mod. Even though the RModSel[1:0] modal parameter can be set arbitrarily for each configuration set, it will not take effect unless enabled via M2. If M2 is driven ‘low’,
R-Mod will be disabled, if M2 is driven ‘high’ R-Mod will be enabled.
5.6.2.3
M2 Configured as AuxOutSrc Override
If M2Config[2:0] is set to ‘111’, M2 when driven ‘high’ will override the AuxOutSrc[1:0] modal parameter and force the AUX_OUT source to PLL Clock Output. When M2 is driven ‘low’, AUX_OUT
will function according to AuxOutSrc[1:0].
14
DS842PP1
CS2200-OTP
5.7
5.7.1
Clock Output Stability Considerations
Output Switching
The CS2200-OTP is designed such that re-configuration of the clock routing functions do not result in a
partial clock period on any of the active outputs (CLK_OUT and/or AUX_OUT). In particular, enabling or
disabling an output, changing the auxiliary output source between REF_CLK and CLK_OUT, and the automatic disabling of the output(s) during unlock will not cause a runt or partial clock period.
The following exceptions/limitations exist:
•
Enabling/disabling AUX_OUT when AuxOutSrc = 11 (unlock indicator).
•
Switching AuxOutSrc[1:0] to or from 11 (unlock indicator)
(Transitions between AuxOutSrc[1:0] = [00,10] will not produce a glitch).
When any of these exceptions occur, a partial clock period on the output may result.
5.7.2
PLL Unlock Conditions
Certain changes to the clock inputs and mode pins can cause the PLL to lose lock which will affect the
presence of a clock signal on CLK_OUT. The following outlines which conditions cause the PLL to go unlocked:
•
Any change in the state of the M1 and M0 pins will cause the PLL to temporarily lose lock as the new
setting takes affect.
•
Changes made to the state of the M2 when the M2Config[2:0] global parameter is set to 011, 100, 101,
or 110 can cause the PLL to temporarily lose lock as the new setting takes affect.
•
Any discontinuities on the Timing Reference Clock, REF_CLK.
DS842PP1
15
CS2200-OTP
6. PARAMETER DESCRIPTIONS
As mentioned in Section 5.1 on page 9, there are two different kinds of parameter configuration sets, Modal and
Global. These configuration sets, shown in Figure 9, can be programmed in the field using the CDK2000 or preprogrammed at the factory. Please see “Programming Information” on page 20 for more details.
M[1:0] pins
Modal Configuration Set #0
Ratio 0
RModSel[1:0]
AuxOutSrc[1:0]
00
RModSel[1:0]
AuxOutSrc[1:0]
01
RModSel[1:0]
AuxOutSrc[1:0]
10
RModSel[1:0]
AuxOutSrc[1:0]
11
Ratio 1
Modal Configuration Set #2
Ratio 2
Modal Configuration Set #3
Ratio 3
Digital/PLL Core
Modal Configuration Set #1
Global Configuration Set
AuxLockCfg
RefClkDiv[1:0]
ClkOutUnl
M2Config[2:0]
Figure 9. Parameter Configuration Sets
6.1
Modal Configuration Sets
There are four instances of each of these configuration parameters. Selection between the four stored sets
is made using the M[1:0] pins.
6.1.1
R-Mod Selection (RModSel[1:0])
Selects the R-Mod value, which is used as a factor in determining the PLL’s Fractional N.
RModSel[1:0]
R-Mod Selection
00
Right-shift R-value by 1 (÷ 2).
01
Right-shift R-value by 2 (÷ 4).
10
Right-shift R-value by 3 (÷ 8).
11
Right-shift R-value by 4 (÷ 16).
Application:
“Manual Ratio Modifier (R-Mod)” on page 11
Note: This parameter does not take affect unless M2 pin is high and the M2Config[2:0] global parameter is set to ‘011’.
16
DS842PP1
CS2200-OTP
6.1.2
Auxiliary Output Source Selection (AuxOutSrc[1:0])
Selects the source of the AUX_OUT signal.
AuxOutSrc[1:0]
Auxiliary Output Source
00
RefClk.
01
Reserved.
10
CLK_OUT.
11
PLL Lock Status Indicator.
Application:
“Auxiliary Output” on page 13
Note: When set to 11, the AuxLockCfg global parameter sets the polarity and driver type (“AUX PLL
Lock Output Configuration (AuxLockCfg)” on page 17).
6.2
Ratio 0 - 3
The four 32-bit User Defined Ratios are stored in the CS2200’s one time programmable memory. See “Output to Input Frequency Ratio Configuration” on page 10 and “Calculating the User Defined Ratio” on
page 19 for more details.
6.3
6.3.1
Global Configuration Parameters
AUX PLL Lock Output Configuration (AuxLockCfg)
When the AUX_OUT pin is configured as a lock indicator (AuxOutSrc[1:0] modal parameter = ‘11’), this
global parameter configures the AUX_OUT driver to either push-pull or open drain. It also determines the
polarity of the lock signal. If AUX_OUT is configured as a clock output, the state of this parameter is disregarded.
AuxLockCfg
AUX_OUT Driver Configuration
0
Push-Pull, Active High (output ‘high’ for unlocked condition, ‘low’ for locked condition).
1
Open Drain, Active Low (output ‘low’ for unlocked condition, high-Z for locked condition).
Application:
“Auxiliary Output” on page 13
Note: AUX_OUT is an unlock indicator, signalling an error condition when the PLL is unlocked. Therefore, the pin polarity is defined relative to the unlock condition.
6.3.2
Reference Clock Input Divider (RefClkDiv[1:0])
Selects the input divider for the timing reference clock.
RefClkDiv[1:0]
Reference Clock Input Divider
REF_CLK Frequency Range
00
÷ 4.
32 MHz to 75 MHz (50 MHz with XTI)
01
÷ 2.
16 MHz to 37.5 MHz
10
÷ 1.
8 MHz to 18.75 MHz
11
Reserved.
Application:
“Internal Timing Reference Clock Divider” on page 9
DS842PP1
17
CS2200-OTP
6.3.3
Enable PLL Clock Output on Unlock (ClkOutUnl)
Defines the state of the PLL output during the PLL unlock condition.
6.3.4
ClkOutUnl
Clock Output Enable Status
0
Clock outputs are driven ‘low’ when PLL is unlocked.
1
Clock outputs are always enabled (results in unpredictable output when PLL is unlocked).
Application:
“PLL Clock Output” on page 12
M2 Pin Configuration (M2Config[2:0])
Controls which special function is mapped to the M2 pin.
18
M2Config[2:0]
M2 pin function
000
Disable CLK_OUT pin.
001
Disable AUX_OUT pin.
010
Disable CLK_OUT and AUX_OUT.
011
RModSel[1:0] Modal Parameter Enable.
100
Reserved.
101
Reserved.
110
Reserved.
111
Force AuxOutSrc[1:0] = 10 (PLL Clock Out).
Application:
“M2 Mode Pin Functionality” on page 14
DS842PP1
CS2200-OTP
7. CALCULATING THE USER DEFINED RATIO
Note:
The software for use with the evaluation kit has built in tools to aid in calculating and converting the User
Defined Ratio. This section is for those who would like to know more about how the User Defined Ratio is
calculated and stored.
Most calculators do not interpret the fixed point binary representation which the CS2200-OTP uses to define the
output to input clock ratio (see Section 5.3.1 on page 10); However, with a simple conversion we can use these tools
to generate a binary or hex value for Ratio0-3 to be stored in one time programmable memory. Please see “Programming Information” on page 20 for more details on programming.
7.1
12.20 Format
To calculate the User Defined Ratio (RUD) to store in the register(s), divide the desired output clock frequency by the given input clock (RefClk). Then multiply the desired ratio by the scaling factor of 220 to get the
scaled decimal representation; then use the decimal to binary/hex conversion function on a calculator and
write to the register. A few examples have been provided in Table 3.
Scaled Decimal
Representation =
(output clock/input clock) • 220
Hex Representation of
Binary RUD
12.288 MHz/10 MHz=1.2288
1288490
00 13 A9 2A
11.2896 MHz/44.1 kHz=256
268435456
10 00 00 00
Desired Output to Input Clock Ratio
(output clock/input clock)
Table 3. Example 12.20 R-Values
DS842PP1
19
CS2200-OTP
8. PROGRAMMING INFORMATION
Field programming of the CS2200-OTP is achieved using the hardware and software tools included with the
CDK2000. The software tools can be downloaded from www.cirrus.com for evaluation prior to ordering a CDK. The
CDK2000 is designed with built-in features to ease the process of programming small quantities of devices for prototype and small production builds. In addition to its field programming capabilities, the CDK2000 can also be used
for the complete evaluation of programmed CS2200-OTP devices.
The CS2200-OTP can also be factory programmed for large quantity orders. When ordering factory programmed
devices, the CDK should first be used to program and evaluate the desired configuration. When evaluation is complete, the CS2000 Configuration Wizard is used to generate a file containing all device configuration information;
this file is conveyed to Cirrus Logic as a complete specification for the factory programming configuration. Please
contact your local Cirrus Logic sales representative for more information regarding factory programmed parts.
See the CDK2000 datasheet, available at www.cirrus.com, for detailed information on the use of the CDK2000 programming and evaluation tools.
Below is a form which represents the information required for programming a device (noted in gray). The “Parameter
Descriptions” section beginning on page 16 describes the functions of each parameter. This form may be used either for personal notation for device configuration or it can be filled out and given to a Cirrus representative in conjunction with the programming file from the CDK2000 as an additional check. The User Defined Ratio may be filled
out in decimal or it may be entered as hex as outlined in “Calculating the User Defined Ratio” on page 19. For all
other parameters mark a ‘0’ or ‘1’ below the parameter name.
OTP Modal and Global Configuration Parameters Form
Modal Configuration Set #0
Ratio 0 (dec)
Ratio 0 (hex) __ __ : __ __ : __ __ : __ __
RModSel1 RModSel0 AuxOutSrc1 AuxOutSrc0
Modal Configuration Set #1
Ratio 0 (dec)
Ratio 0 (hex) __ __ : __ __ : __ __ : __ __
RModSel1 RModSel0 AuxOutSrc1 AuxOutSrc0
Modal Configuration Set #2
Ratio 0 (dec)
Ratio 0 (hex) __ __ : __ __ : __ __ : __ __
RModSel1 RModSel0 AuxOutSrc1 AuxOutSrc0
Modal Configuration Set #3
Ratio 0 (dec)
Ratio 0 (hex) __ __ : __ __ : __ __ : __ __
RModSel1 RModSel0 AuxOutSrc1 AuxOutSrc0
Global Configuration Set
AuxLockCfg RefClkDiv1
20
RefClkDiv0
ClkOutUnl
M2Cfg2
M2Cfg1
M2Cfg0
DS842PP1
CS2200-OTP
9. PACKAGE DIMENSIONS
10L MSOP (3 mm BODY) PACKAGE DRAWING (Note 1)
N
D
E11
c
E
A2
A
∝
e
b
A1
SIDE VIEW
1 2 3
END VIEW
L
SEATING
PLANE
L1
TOP VIEW
DIM
MIN
INCHES
NOM
A
A1
A2
b
c
D
E
E1
e
L
L1
-0
0.0295
0.0059
0.0031
----0.0157
--
-----0.1181 BSC
0.1929 BSC
0.1181 BSC
0.0197 BSC
0.0236
0.0374 REF
MAX
0.0433
0.0059
0.0374
0.0118
0.0091
----0.0315
--
MIN
MILLIMETERS
NOM
NOTE
MAX
-0
0.75
0.15
0.08
----0.40
--
-----3.00 BSC
4.90 BSC
3.00 BSC
0.50 BSC
0.60
0.95 REF
1.10
0.15
0.95
0.30
0.23
----0.80
--
4, 5
2
3
Notes: 1. Reference document: JEDEC MO-187
2. D does not include mold flash or protrusions which is 0.15 mm max. per side.
3. E1 does not include inter-lead flash or protrusions which is 0.15 mm max per side.
4. Dimension b does not include a total allowable dambar protrusion of 0.08 mm max.
5. Exceptions to JEDEC dimension.
THERMAL CHARACTERISTICS
Parameter
Junction to Ambient Thermal Impedance
DS842PP1
JEDEC 2-Layer
JEDEC 4-Layer
Symbol
Min
Typ
Max
Units
θJA
θJA
-
170
100
-
°C/W
°C/W
21
CS2200-OTP
10.ORDERING INFORMATION
The CS2200-OTP is ordered as an un-programmed device. The CS2200-OTP can also be factory programmed for
large quantity orders. Please see “Programming Information” on page 20 for more details.
Product
Description
Package
Pb-Free
CS2200-OTP
Clocking Device
10L-MSOP
Yes
CS2200-OTP
Clocking Device
10L-MSOP
Yes
CDK2000
Evaluation Platform
-
Yes
Grade
Commercial
-
Temp Range Container
Order#
-10° to +70°C
Rail
CS2200P-CZZ
-10° to +70°C
Tape and
Reel
CS2200P-CZZR
-
-
CDK-2000-CLK
11.REVISION HISTORY
Release
A1
PP1
Changes
Initial Release
Updated “AC Electrical Characteristics” on page 7
Contacting Cirrus Logic Support
For all product questions and inquiries, contact a Cirrus Logic Sales Representative.
To find one nearest you, go to www.cirrus.com.
IMPORTANT NOTICE
“Preliminary” product information describes products that are in production, but for which full characterization data is not yet available.
Cirrus Logic, Inc. and its subsidiaries (“Cirrus”) believe that the information contained in this document is accurate and reliable. However, the information is subject
to change without notice and is provided “AS IS” without warranty of any kind (express or implied). Customers are advised to obtain the latest version of relevant
information to verify, before placing orders, that information being relied on is current and complete. All products are sold subject to the terms and conditions of sale
supplied at the time of order acknowledgment, including those pertaining to warranty, indemnification, and limitation of liability. No responsibility is assumed by Cirrus
for the use of this information, including use of this information as the basis for manufacture or sale of any items, or for infringement of patents or other rights of third
parties. This document is the property of Cirrus and by furnishing this information, Cirrus grants no license, express or implied under any patents, mask work rights,
copyrights, trademarks, trade secrets or other intellectual property rights. Cirrus owns the copyrights associated with the information contained herein and gives consent for copies to be made of the information only for use within your organization with respect to Cirrus integrated circuits or other products of Cirrus. This consent
does not extend to other copying such as copying for general distribution, advertising or promotional purposes, or for creating any work for resale.
CERTAIN APPLICATIONS USING SEMICONDUCTOR PRODUCTS MAY INVOLVE POTENTIAL RISKS OF DEATH, PERSONAL INJURY, OR SEVERE PROPERTY OR ENVIRONMENTAL DAMAGE (“CRITICAL APPLICATIONS”). CIRRUS PRODUCTS ARE NOT DESIGNED, AUTHORIZED OR WARRANTED FOR USE
IN PRODUCTS SURGICALLY IMPLANTED INTO THE BODY, AUTOMOTIVE SAFETY OR SECURITY DEVICES, LIFE SUPPORT PRODUCTS OR OTHER CRITICAL APPLICATIONS. INCLUSION OF CIRRUS PRODUCTS IN SUCH APPLICATIONS IS UNDERSTOOD TO BE FULLY AT THE CUSTOMER’S RISK AND CIRRUS DISCLAIMS AND MAKES NO WARRANTY, EXPRESS, STATUTORY OR IMPLIED, INCLUDING THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS FOR PARTICULAR PURPOSE, WITH REGARD TO ANY CIRRUS PRODUCT THAT IS USED IN SUCH A MANNER. IF THE CUSTOMER OR CUSTOMER’S CUSTOMER USES OR PERMITS THE USE OF CIRRUS PRODUCTS IN CRITICAL APPLICATIONS, CUSTOMER AGREES, BY SUCH USE, TO FULLY
INDEMNIFY CIRRUS, ITS OFFICERS, DIRECTORS, EMPLOYEES, DISTRIBUTORS AND OTHER AGENTS FROM ANY AND ALL LIABILITY, INCLUDING ATTORNEYS’ FEES AND COSTS, THAT MAY RESULT FROM OR ARISE IN CONNECTION WITH THESE USES.
Cirrus Logic, Cirrus, and the Cirrus Logic logo designs are trademarks of Cirrus Logic, Inc. All other brand and product names in this document may be trademarks
or service marks of their respective owners.
22
DS842PP1
Similar pages