EVB8720 Evaluation Board Schematic

5
4
3
2
1
LAN8720A RMII PHY Customer Evaluation Board
Assy 6584
D
D
PCB Revision C
Schematic Revision 1.3
Design Details
Board:
Assy 6584
Chip:
SMSC LAN8720A
C
Circuit Diagrams utilizing SMSC Products Are
Included As A Means Of Illustrating Typical
Semiconductor Applications: Consequently
Complete Information Sufficient For Construction
Purposes Is Not Necessarily Given. The Information
Has Been Carefully Checked And Is Believed To Be
Entirely Reliable. However, No Responsibility Is
Assumed For Inaccuracies. Furthermore, Such
Information Does Not Convey To The Purchaser Of
The Semiconductor Devices Described Any License
Under The Patent Rights Of SMSC Or Others. SMSC
Reserves The Right To Make Changes At Any Time In
Order To Improve Design And Supply The Best
Product Possible.
Board Form Factor:
MII Add-On Card
Assembly:
24 Lead QFN w/ Exposed GND Pad
Revision History
ITEM
BLOCK DIAGRAM
Rev 1.0:
Initial release, Rev C
C
Page(s)
Title Page
LAN8720A / RMII / Magnetics
1
Configuration Settings
3
2
Rev 1.1:
B
U3 (page 2) - Changed from
74LVC1G07 to 74LVC1G17
in rework prior to release of
all Revision C boards.
B
"Configuration Resistor
Settings" (Pg. 03): Created
new table.
Configuration Resistor
Settings" table, (Pg. 03):
Correction to signal name
within table from
"nINT/TXEN/TXD4" to
"nINT/REFCLKO Signal".
Added text to signal "nINT"
pull-up jumper.
Rev 1.2:
All Pages - Changed from
LAN8720 to LAN8720A
Rev 1.3:
A
C19 changed from 0.1uF
to 470pF.
A
Title
LAN8720A RMII PHY Customer Evaluation Board
Size
Assembly No.
Engineer
R. W.
Date:
5
4
3
2
6584
Tuesday, May 18, 2010
1
PCB Rev
Schematic Rev
C
Sheet
1.3
1
of
3
5
4
3
2
1
LAN8720A / Magnetics / RMII Connector
VDDCR Decoupling Capacitors
+5V
AVDD
+3.3V
VR1
1
TP2
C1
1.0uF
16V
10%
Test Point - Red
+5V
D
VDDCR
FB1
OUT
5
2
GND
3
ON/OFF BYPS
4
Vin
2.0A/0.050 DCR
TP3
TP1
LP2992IM5-3.3
SOT23-5
C4
0.01uF
50V
10%
+5V
Test Point - Green
VDDCR
DNP
Test Point - Orange
+3.3V
C2
4.7uF
6.3V
10%
C18
0.1uF
16V
10%
R12
0
TP5
RMII +5V decoupling capacitors to
be placed near RMII connector
C5
0.1uF
16V
10%
C6
0.1uF
16V
10%
C3
4.7uF
6.3V
10%
C19
470pF
50V
5%
C20
1.0uF
16V
10%
D
C21
4.7uF
6.3V
10%
DNP
Note:
C19& C20 decoupling
capacitors for VDDCR
should be placed as
close to LAN8720A
as possible.
C21 is for internal use
only.
Test Point - Purple
VDDIO
+
C16
0.1uF
16V
10%
Note:
Place 0 Ohm resistor close
to magnetics module .
C17
10uF
25V
10%
-
VDDIO
VDDCR
R13
49.9
1/10W
1%
R14
49.9
1/10W
1%
R15
49.9
1/10W
1%
R16
49.9
1/10W
1%
R17
0
Place 49.9 Ohm resistors
close to LAN8720A.
LED1_CATHODE
LED1_ANODE
R_CRS
R10
100
nRST
9
A
C
6
2
RXP
23
RXN
22
CRS_DV/MODE2
LED1/REGOFF
LED2/nINTSEL
15
RCV
RXP
3
LAN8720A
TXEN
TXD0
TXD1
11
U1
DNP
5173278-2
TD-
LED1 (Green) = LINK/ACT
nINT/REFCLKO
RXER/PHYAD0
16
17
18
CRS_DV/MODE2
2
RXN
3
2
LED1/REGOFF
LED2/nINTSEL
24
RBIAS
C8
0.022uF
50V
10%
5
XTAL1/CLKIN
XTAL2
4
XTAL2
25
XTAL1/CLKIN
RBIAS
75
5
RXCT
6
RD-
QFN24_4X4MM_EP2P5MM
C9
10pF
50V
5%
DNP
R22
12.1K
1/10W
1%
C10
10pF
50V
5%
DNP
C11
10pF
50V
5%
DNP
6
1000 pF
NC
8
CHS GND
C12
10pF
50V
5%
DNP
C
3
75
7&8
7
nRST
LED2 (Yellow) = SPEED
RD+
2 kV
YEL
A
14
10
TXEN
TXD0
TXD1
TXN
RXD1/MODE1
RXD0/MODE0
12
TXCLK
TXEN
TXD0
TXD1
nINT/REFCLKO
RXER/PHYAD0
20
1
75
C
100
TXN
7
8
4&5
75
11
R7
RXD1/MODE1
RXD0/MODE0
TXCT
MTG
100
100
100
TD+
4
MTG
R3
R4
R5
MDIO
MDC
16
R_RXD1
R_RXD0
R_RXDV
R_RXCLK
R_RXER
12
13
15
MDIO
MDC
MDIO
MDC
GND
+5V
MDIO
MDC
RXD3
RXD2
RXD1
RXD0
RX_DV
RX_CLK
RX_ER
TX_ER
TX_CLK
TX_EN
TXD0
TXD1
TXD2
TXD3
COL
CRS
+5V
RJ45
1
GND
HEADER_2x10
RMII Signal Test
Point Header
+5V
GND
GND
GND
GND
GND
GND
GND
GND
GND
GND
GND
GND
GND
GND
GND
GND
GND
GND
+5V
TXP
TXP 21
14
MDIO
R_RXD0
R_RXCLK
TXCLK
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
GRN
XMIT
13
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
21
VDD2A
VDD1A
2
4
6
8
10
12
14
16
18
20
GND_EP
C
P1
1
3
5
7
9
11
13
15
17
19
nRST
MDC
R_RXD1
R_RXER
nINT
TXEN
TXD0
TXD1
R_CRS
VDDIO
J1
10
T1
Pulse J0011D01BNL
VDDCR
+5V
1
19
VDDIO
C7
0.1uF
16V
10%
9
+3.3V
R11
1.50K
1/10W
1%
LED2_ANODE
LED2_CATHODE
Reset Generator
Note:
Capacitors C9 through C12 are optional for EMI purposes
and are not populated on the LAN8720A evaluation
board. These capacitors are required for operation in an
EMI constrained environment.
VDDIO
+3.3V
R44
4.75K
1%
U4
VTH = 2.63V
Treset = 20 mS
R51
4
VCC
3
MR
nRST
2
RESET
VDDIO
10.0K
B
SPST_MOM
1
C15
0.1uF
10V
10%
B
R25
4.75K
TXCLK
MIC6315-26D2UY
SOT-143_BIG1
TXCLK
0
R49
XTAL1/CLKIN
nINT
DNP
RMII Clock Source Selection Jumpers
REGOFF & INTSEL Configuration Resistors
PHY Address / nINT Strap / Mode Select Resistors
REGOFF
R45
1
2
3
XTAL1
LED1/REGOFF
1
EXTCLK50
0
1
REFCLKO
LED1/REGOFF
1
2
3
nINT/REFCLKO
XTAL2
EN
R20
10.0
1/10W
1%
4
2
GND
OUT
3
50.000MHz
CLK50 2
3
C22
0.1uF
10V
10%
TP4
R29
4.75K
1/10W
1%
Test Point - Black
GND
R30
4.75K
1/10W
1%
LED1_CATHODE
MTG1
1
MTG2
1
NC
VDDIO
RXD1/MODE1
CRS_DV/MODE2
nINTSEL
VCC
5
IN
OUT
4
LED2/nINTSEL
1
1
R42
LED2_ANODE
3
25.000MHz
HC49US
1
GND
C13
30pF
50V
5%
3 Plated Hole w_GND
RXER/PHYAD0
0
C23
0.1uF
10V
10%
3 Plated Hole w_GND
A
Y1
2
NC
74LVC1G17
C14
30pF
50V
5%
LED2/nINTSEL
R37
4.75K
1/10W
1%
R39
4.75K
1/10W
R43
2
LED2_CATHODE
R33
4.75K
1/10W
1%
DNP
R32
4.75K
1/10W
1%
DNP
3
R31
4.75K
1/10W
1%
DNP
Title
330
LAN8720A / Magnetics / (R)MII Connector
Size
Assembly No.
Engineer
R. W.
Date:
5
NC
RXD0/MODE0
U3
1
0
AVDD
2
VCC
R28
4.75K
1/10W
1%
330
3
1
R23
3-Pad Resistor Default Population Settings: 1--2
U2
R48
4.75K
R24
4.75K
1/10W
1%
DNP
DNP
0
A
MODE0
3
1.00M
EXTCLK50
Note:
U3 must be depopulated when
sourcing a 50MHz external (offboard)
clock via the R_RXCLK pin.
R47
4.75K
DNP
R21
2
MODE1
1210
R38
4.75K
1/10W
R41
MODE2
LED1_ANODE
3
3-Pad Resistor Default Population Settings: 1--2
R_RXCLK
PHYADD0
R40
2
0
R46
nINT/REFCLKO
VDDIO
CLKIN
+3.3V
0
R50
DNP
AVDD
XTAL1/CLKIN
nINT
50MHz TX Clock Signal Input
(if provided on TXCLK by RMII MAC)
GND
S1
4
3
2
6584
Thursday, January 06, 2011
1
PCB Rev
Schematic Rev
C
Sheet
1.3
2
of
3
5
4
3
2
1
Configuration Settings
D
D
Configuration Settings
C
B
SIGNAL
POPULATE
DEPOPULATE
PHYAD[0] = 0
R37
R24
PHYAD[0] = 1
R24
R37
MODE[0] = 0
MODE[1] = 0
MODE[2] = 0
R31
R32
R33
R30
R29
R28
MODE[0] = 1
MODE[1] = 1
MODE[2] = 1
R30
R29
R28
R31
R32
R33
Default
Default
Default
Internal 1.2V Reg. Enabled
Internal 1.2V Reg. Disabled
R40 & R41: 1-2
R40 & R41: 2-3
R40 & R41: 2-3
R40 & R41: 1-2
Default
Interrupt Function Enabled on
nINT/TXER/TXD4 Signal
R50,
R42 & R43: 2-3
R42 & R43: 1-2
Interrupt Function Disabled on
nINT/TXER/TXD4 Signal
R42 & R43: 1-2
R50,
R42 & R43: 2-3
Default
25.000MHz Crystal Clock Source Enabled
R20, R48,
R45 & R46: 1-2
R47, R49
R45 & R46: 2-3
Default
25MHz Crystal Clock Source Disabled, with
Offboard 50MHz Clock Source Provided on
TXCLK
R48, R49
R20, R47,
R45 & R46: 1-2
R45 & R46: 2-3
Interrupt Function must be enabled in this configuration.
25MHz Crystal Clock Source Disabled, with
Offboard 50MHz Clock Source Provided on
RXCLK
R48,
R45 & R46: 2-3
U3, R20, R47, R49
R45 & R46: 1-2
Interrupt Function must be enabled in this configuration.
25MHz Crystal Clock Source Disabled, with
Onboard 50MHz Clock Source Provided on
RXCLK
U3, R47,
R45 & R46: 2-3
R20, R48, R49
R45 & R46: 1-2
Interrupt Function must be enabled in this configuration.
25MHz Crystal Clock Source Disabled, with
Onboard 50MHz Clock Source Provided on
RXCLK via REFCLK0
U3, R47,
R45: 2-3
R46: 1-2
R20, R48, R49
R45: 1-2
R46: 2-3
Interrupt Function must be disabled in this configuration.
COMMENTS
Default
C
Interrupt Function must be disabled in this configuration.
B
A
A
Title
Configuration Settings
Size
Assembly No.
Engineer
R. W.
Date:
5
4
3
2
6584
Tuesday, May 18, 2010
1
PCB Rev
Schematic Rev
C
Sheet
1.3
3
of
3