ispClock5620 Evaluation Board ispPAC-CLK5620-EV1

ispClock5620 Evaluation Board:
ispPAC-CLK5620-EV1
November 2004
Application Note AN6064
Introduction
The Lattice Semiconductor ispClock™5620 In-System-Programmable Analog Circuit allows designers to implement clock distribution networks supporting multiple, synchronized output frequencies using a single integrated circuit.
By integrating a Phase-Locked Loop (PLL) along with multiple output dividers, the ispClock5620 can derive up to
five separate output frequencies from a single input reference frequency. To facilitate the implementation of widefanout clock trees, the ispClock5620 provides up to 20 single-ended outputs or 10 differential outputs, organized as
ten banks of two. Each output bank may be independently programmed to support different logic standards and
operating options. Additionally, each single-ended output or differential output may be skew-adjusted to compensate for the effects of propagation delay along the PCB traces used in the distribution network. All configuration
data is stored internally in E2CMOS® non-volatile memory. Programming a configuration is accomplished through
an industry-standard JTAG IEEE 1149.1 interface.
Figure 1. ispPAC-CLK5620-EV1 Evaluation Board
ispPAC-CLK5620-EV1 Evaluation Board
The ispPAC-CLK5620-EV1 evaluation board (Figure 1) allows the designer to quickly configure and evaluate the
ispClock5620 on a fully assembled printed-circuit board. The four-layer board supports a 100-pin TQFP package, a
header for user I/O and a JTAG programming cable connector. SMA connectors are installed to provide high-signal
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an6064_01
ispClock5620 Evaluation Board:
ispPAC-CLK5620-EV1
Lattice Semiconductor
integrity access to selected high-speed I/O signals. JTAG programming signals can be generated by using an ispDOWNLOAD® programming cable connected between the evaluation board and a PC’s parallel (printer) port. All
user-programmable features of the ispPAC-CLK5620 can be easily configured using Lattice Semiconductor’s PACDesigner® software.
Programming Interface
Lattice Semiconductor’s ispDOWNLOAD cable can be used to program the ispClock5620 which is provided on the
evaluation board. This cable plugs into a PC-compatible’s parallel port connector, and includes active buffer circuitry inside its DB-25 connector housing. The other end of the ispDOWNLOAD cable terminates in an 8-pin 0.100”
pitch header connector which plugs directly into a mating connector provided on the ispPAC-CLK5620-EV1 evaluation board.
Power Supply Considerations
The ispClock5620 operates with analog and digital core power supplies of 3.3V, while each output driver has a dedicated power supply pin which may be driven with supply voltage of 1.5V, 1.8V, 2.5V or 3.3V, depending on the logic
standard which it has been configured to drive.
To simplify evaluation work, the ispPAC-CLK5620-EV1 board was designed to operate from a single 4.5V-5.5V
power supply, which may be brought in through either a pair of banana plugs (J2 and J3), or a standard 5mm power
plug (J1 - center tip positive). The evaluation board provides two linear regulators to provide the appropriate operating voltages for the ispClock5620. One of these regulators provides a fixed 3.3V for the analog and core functions,
while the other regulator is dipswitch-programmable to provide 1.5V, 1.8V, 2.5V and 3.3V to power the BANK8 and
BANK9 output drivers.
Input/Output Connections
Connectors are provided for key functions and test points on this evaluation board, as shown In Figure 2. Power
may be supplied in one of two ways; either through two color coded (RED = +, BLACK = -) banana jacks in the
upper right corner of the board or through a 5mm (center pin +) DC power connector (J1), The JTAG programming
cable is connected to a keyed header (J4) in the upper right corner of the board.
Access to a subset of the ispClock5620’s I/O pins is available at J5, which is a 2x17 row of pads to which one may
attach test probes or a ribbon-cable connector. At this point most of the device’s non-RF control pins (except those
required for the JTAG programming interface) are accessible.
SMA connectors are provided along the left and right edges of the board to support access to key high-speed I/O
pins. Pairs of connectors are provided for the BANK8 and BANK9 outputs (J10-J13). Additional pairs of connectors
are provided for REFA(+/-) clock reference inputs (J8, J9) and FBKA (+, -) external feedback inputs (J6, J7). On this
evaluation board design the REFB(+/-) clock inputs are dedicated to supporting an on-board crystal oscillator.
Because this board was designed to maintain high levels of signal integrity at the edge rates at which the
ispClock5620 operates, it is strongly suggested that the user do not attempt to access any of the device’s highspeed I/O except through the provided SMA connectors and supporting impedance-controlled printed-circuit
traces.
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ispClock5620 Evaluation Board:
ispPAC-CLK5620-EV1
Lattice Semiconductor
Figure 2. I/O Connections, Controls and Indicators
Controls and Indicators
A 12-position dipswitch (S2) is provided on the evaluation board (Figure 2) for the purpose of setting device inputs
and programming the VCCO power supply for the BANK8 and BANK9 outputs. The following table shows the
options controlled by each switch:
Table 1. User Configuration Functions
Position
Function (when ON)
1
PLL_BYPASS
2
PS0
3
PS1
4
GOE
5
SGATE
6
REFSEL
7
OEX
8
OEY
9
OSC DIS
10
11
BANK8 and BANK9 VCCO Programming
12
Each of the switch positions used to control logic inputs (positions 1-8) pulls its respective control signal HIGH
when it is turned on. Each of these switch outputs is connected to the device through a 1KΩ resistor. This feature
allows external CMOS logic control signals applied to the J5 header connector to over-ride the on-board switch settlings.
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ispClock5620 Evaluation Board:
ispPAC-CLK5620-EV1
Lattice Semiconductor
Switch position 9 (OSC DIS) is used to control the evaluation board’s on-board clock oscillator. When this switch is
set to the OFF position the on-board 100MHz oscillator is active and when it is the ON position it is disabled. Disabling the on-board oscillator is desirable when an external clock source is used as an input reference signal
because doing so reduces the jitter measured at the board’s output. Note that if the on-board source is selected
(REFSEL switch = ON) the on-board clock must not be disabled.
Switch positions 10-12 are used to program the VCCO supply for output banks 8 and 9. When all of these switches
are OFF, the default supply VCCO supply is 3.3V. The following table shows the switch configurations needed to
develop standard supply voltages:
Table 2. VCCO Programming Switch (S2) Configurations
S2 Switch Position
10
11
12
VCCO
OFF
OFF
OFF
3.3V
ON
OFF
OFF
1.5V
OFF
ON
OFF
1.8V
OFF
OFF
ON
2.5V
A reset switch (S1) is provided on the evaluation board which pulls the RESET input pin HIGH when it is
depressed, re-initializing the ispClock5620. After changing profiles or reprogramming the ispClock5620 it is necessary to reset the device to obtain a stable clock output.
Several LEDs are also provided on the evaluation board to indicate proper function and as aids to debugging. LED
D2 (red) indicates that the on-board 3.3V supply is powered up. LED D3 (yellow) is connected to the
ispClock5620’s TDO line, and will briefly flash when downloading, indicating that download data has made it to the
device. Finally, when LED D4 (green) is lit, this indicates that the ispClock5620’s PLL is in a ‘locked’ state.
Schematics
The following three figures comprise the schematics for the ispPAC-CLK5620-EV1 evaluation board. Figure 3
shows the on-board power-conditioning circuitry, Figure 4 shows the high-speed interconnects and on-board oscillator circuitry, while Figure 5 shows all the logic control signals and indicators.
Figure 3. On-Board Power Supplies
U2
GND BANANA
(BLACK)
C1
100uF
J2
C4
0.1uF
TPS77733
GND
+5V BANANA
(RED)
3
IN
4
IN
1
5
OUT
6
OUT
V33
C5
0.1uF
C2
10 uF
ENb
D1
J3
2
J1
5mm
Power Jack
U3
S2.10
OFF
OFF
S2.11
OFF
OFF
S2.12
OFF
ON
VCCO
3.30 V
2.50 V
OFF
ON
ON
OFF
OFF
OFF
1.80 V
1.50 V
TPS77701
1
ENb
Output Voltage vs. Switch Settings
OUT
GND
C6
0.1uF
3
IN
4
IN
OUT
FB
2
5
VCCO
6
R2 178K 1%
7
R1
100K
1%
4
S2.10
R3 300K 1%
S2.11
R4 73.2K 1%
S2.12
R5 31.6K 1%
C7
0.1uF
C3
10uF
ispClock5620 Evaluation Board:
ispPAC-CLK5620-EV1
Lattice Semiconductor
Figure 4. Oscillator and High-Speed I/O
V33
V33
C11
0.1u
REFA-
J8
39
J9
V33
VCCD
REFA+
47
71
VCCJ
REFA+
38
VCCD
74
C12
0.1u
VCCA
GNDA
REFA-
FB1
30
31
C9
0.1u
VCCO
V33
FBKA+
FB2
FBKAC11
0.1u
6
FBKVTT
VCC
1
OSC1
(note 1)
EN
OUT
32
J6
33
J7
34
J5.24
4
41
5
42
OUT
GND
3
40
REFVTT J5.25
S2.9
FBKA+
VCCO9
U1
FBKA-
GNDO9
FBKVTT
BANK9A
BANK9B
REFB-
R282
100
C13
0.1u
70
69
BANK9A
J10
68
BANK9B
J11
VCCO
REFVTT
GNDO8
32
GNDD
33
GNDD
34
GNDD
35
GNDD
36
GNDD
37
GNDD
BANK8A
66
C14
0.1u
65
BANK8A
J12
64
BANK8B
J13
GNDD
GNDD
FB4
63
93
46
GNDO6
GNDO5
GNDO7
62
58
GNDO4
54
22
GNDO2
GNDO1
GNDO3
18
6
Notes:
1. If OSC1 is LVCMOS type, omit R27,R28
If OSC1 is DPECL type, for external termination
install R27,R28
2. Not populated
14
GNDO0
BANK8B
10
R272
100
67
ispClock5620
REFB+
VCCO8
Oscillator
DISABLED
when
closed
FB3
J5.3
J5.29
J5.15
J5.17
J5.19
J5.9
J5.11
J5.13
J5.5
J5.7
Figure 5. User Controls and Miscellaneous I/O
U1
ispClock5620
V33
92
S2.1
PLL_BYPASS
R16 1K
S2.2
PS0
R17 1K
S2.3
PS1
R18 1K
S2.4
GOE
R19 1K
S2.5
SGATE
R20 1K
S2.6
REFSEL
R21 1K
S2.7
OEX
R22 1K
S2.8
OEY
R23 1K
89
88
87
85
43
44
45
R7 1K
R8 1K
R9 1K
R10 1K
R11 1K
R12 1K
R13 1K
R14 1K
72
V33
R26
680
V33
GOE
Jx.1 VS
SGATE
REFSEL
OEX
TDO
TDI
73
84
Jx.2 TDO
Jx.3 TDI
Jx.4 n/c
OEY
R6 1K
5
RESET
R24
680
D2
POWER
R25
680
D3
TDO
TMS
91
82
LOCK
TEST2
TEST1
Jx.6 TMS
Jx.7 GND
TCK
90
R15
2.2K
C8
0.1u
PS1
D4
LOCK
V33
S1
PS0
Jx.5 plug
86
RESET
PLL_BYPASS
83
Jx.8 TCK
ispClock5620 Evaluation Board:
ispPAC-CLK5620-EV1
Lattice Semiconductor
PCB Artwork
Figure 6. Silk Screen
Figure 7. Component Side Copper (Layer 1)
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ispClock5620 Evaluation Board:
ispPAC-CLK5620-EV1
Lattice Semiconductor
Figure 8. Ground Plane (Layer 2)
Figure 9. Power Plane (Layer 3)
7
ispClock5620 Evaluation Board:
ispPAC-CLK5620-EV1
Lattice Semiconductor
Figure 10. Solder-side Copper (Layer 4)
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ispClock5620 Evaluation Board:
ispPAC-CLK5620-EV1
Lattice Semiconductor
Component List
Reference
Designators
Quantity
Description
1
n/a
ispPAC-CLK5620-EV1 Printed Wiring Board
1
C1
100µF 10V tantalum capacitor, Panasonic ECS-T1AD107R
2
C2, C3
10µF 10V tantalum capacitor, Panasonic ECS-T1AX106R
5
C4, C5, C6, C7, C8
0.1µF 16V capacitor SMD0805, Panasonic ECJ-2VB1C104K
6
C9, C10, C11, C12, C13, C14
0.1µF 16V capacitor SMD0603, Panasonic ECJ-1VB1C104K
1
D1
Schottky rectifier, International Rectifier MRBS130LTR
1
D2
Red LED SMD1206, LiteOn LTST-C150KRKT
1
D3
Yellow LED SMD1206, LiteOn LTST-C150KYKT
1
D4
Green LED SMD1206, LiteOn LTST-C150KGKT
4
FB1, FB2, FB3, FB4
SMD0603 Ferrite Bead, Steward MI0603J600R-00
1
J1
DC Power Connector, CUI PJ-102BH
1
J2
Banana Jack Red, SPC Technologies 845-R
1
J3
Banana Jack Black, SPC Technologies 845-B
1
J4
8-Position Single-Row Header, Molex 22-28-4084
1
J5
34-position Dual Row Header (Not Populated), Molex 10-88-1341
8
J6, J7, J8, J9, J10, J11, J12, J13
SMA Connector, Amphenol 901-144-8RFX
1
R1
100k 1% SMD0805 Resistor, Yageo 9C08052A1003FKHFT
1
R2
178k 1% SMD0805 Resistor, Yageo 9C08052A1783FKHFT
1
R3
300k 1% SMD0805 Resistor, Yageo 9C08052A3003FKHFT
1
R4
73.2k 1% SMD0805 Resistor, Yageo 9C08052A7322FKHFT
1
R5
31.6k 1% SMD0805 Resistor, Yageo 9C08052A3162FKHFT
18
R6, R7, R8, R9, R10, R11, R12, R13, R14, R15,
1K 5% SMD0805 Resistor, Yageo 9C08052A1001JLHFT
R16, R17, R18, R19, R20, R21, R22, R23
3
R24, R25, R26
680Ω 5% SMD0805 Resistor, Yageo 9C08052A6800JLHFT
2
R271, R281
100Ω 1% SMD0603 Resistor, Panasonic ERJ-3EKF1000V
1
S1
Momentary Tactile Switch, Panasonic EVQPAD04M
1
S2
12-position dipswitch, CTS 206-12ST
1
U1
ispClock5620 (ispPAC-CLK5620V-01T100I)
1
U2
3.3V fixed regulator SOIC8, Texas Instruments TPS77733D
1
U3
Adjustable regulator SOIC8, Texas Instruments TPS77701D
2
1
X1
100MHz LVCMOS Oscillator, ECS-3953M-1000-B
4
n/a
Rubber Feet, 3M SJ-5003
1. Install only for use with differential PECL oscillator – see note 2.
2. Lower jitter performance may be obtained by using NEL Frequency Controls type SD-A2920/100.00MHz Differential PECL oscillator. If this
device is installed, R27, R28 must be populated.
Technical Support Assistance
Hotline: 1-800-LATTICE (North America)
+1-408-826-6002 (Outside North America)
e-mail: [email protected]
Internet: www.latticesemi.com
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