Figure 3-55. J-Link-OB with J-Link-CDC Interface Schematic
LED1_3U
LED2_3U
39R 0402 1%
R256
0.1uF
10V
0402
C253
0.01uF
50V
0402
C245
1N4148
D9
4.7uF
10V
0402
C252
2.2uF
16V
0603
C267
0.1uF
10V
0402
C250
39R 0402 1%
R257
0.1uF
10V
0402
C257
6.8k 0402 1%
R250
04
75
89
00
01
ID 4
VBUS 1
GND 5
D- 2
D+ 3
0
J24
0.1uF
10V
0402
C260
10k
0402
1%
R247
0.1uF
10V
0402
C261
10pF
50V
0402
C248
150R
R246
0.01uF
50V
0402
C247
0.1uF
10V
0402
C265
ATSAM3U4CA-CU
VD
DA
NA
K2
ADVREF
J3
GN
DA
NA
K3
AD12BVREF
K4
PA22/PGMD14 H4
PA30 J4
PB
3
J5
PB
4
K5
VD
DC
OR
E_
3
E7
PA13/PGMD5 H5
GN
D2
F6
PA15/PGMD7 H6
PA16/PGMD8 J6
PA17/PGMD9 K7
PB
16
F7
PB
15
G7
PA18/PGMD10 H7
PA19/PGMD11 J7
PA20/PGMD12 K8
PA21/PGMD13 J8
PA23/PGMD15 K9
XIN32
A10
PA24 H8
PA25 K10
PA26 J9
PA0/PGMNCMD J10
PA1/PGMRDY H9
PA2/PGMNOE H10
PA3/PGMNVALID G8
PA4/PGMM0 G10
PA5/PGMM1 G9
PA6/PGMM2 F8
NRST
B7
VD
DC
OR
E_
4
H1
GN
D1
E2
VD
DI
O_
3
E6
VD
DC
OR
E_
5
G5
DFSDM
D1
GN
D3
G6
VD
DU
TM
I
B3
VD
DI
N
A8
FWUP
D8
ERASE
D6
TEST
D7
XIN
A2
XOUT32
B10
TDI
B9
VD
DO
UT
A9
PA12/PGMD4 D10
TDO/TRACESWO
B8
TMS/SWDIO
C7 TCK/SWCLK
A7
PA7/PGMM3 F10
PB
24
B6
PA8/PGMD0 E10
VD
DI
O_
2
F5
PA14/PGMD6 K6
PB
23
A6
PB
22
C6
PB
14
C4
PB
10
B4
PB
9
E4
GN
DP
LL
C3
PB
8
J2
PB
7
K1
PB
6
J1
PB
13
G4
PB
12
F2
PB
11
G1
PB
2
G2
PB
1
F1
PB
0
G3
PA10/PGMD2 E8
VD
DI
O_
1
F3
VD
DC
OR
E_
1
B1
PA31 F4
PA29 E1
PA28 E3
VD
DC
OR
E_
2
D4
GN
DU
TM
I
B2
DFSDP
C1
DHSDM
D2
DHSDP
C2
NRSTB
C8
XOUT
A3
VD
DP
LL
D3
PA11/PGMD3 D9
PA9/PGMD1 E9
PB
20
D5
PB
19
C5
PB
18
B5
PB
17
A4
PB
5
H2
PA27 H3
PB
21
A5
VD
DB
U
C1
0
GN
DB
U
E5
VBG
A1
JTAGSEL
C9
VD
DC
OR
E_
6
F9
U26
AT
SA
M
3U
4C
A-
C
U
TF
BG
A-
10
0
0.1uF
10V
0402
C259
2
1
4
3
GREEN
RED
0805
D10
0.1uF
10V
0402
C263
0.1uF
10V
0402
C255
0.1uF
10V
0402
C254
4.7uF
10V
0402
C258
0.1uF
10V
0402
C251
2.2uF
16V
0603
C268
0.1uF
10V
0402
C249
0.1uF
10V
0402
C262
0.1uF
10V
0402
C266
0.1uF
10V
0402
C269
0.1uF
10V
0402
C264
GND
GND
VDD_3V3_3U
GND
GND
VBUS_JLINK
VDD_3V3_3U
VDD_3V3_3U
EARTH0
GND
GND
VDD_3V3_3U
GND
GND
VDD_3V3_3U
GND
VDD_3V3_3U
VBUS_JLINK
GND
VDD_3V3_3U
JLINK
SAM3U
BOT
TOP
Side
Side
1
2
3
4
7
8
9
10
11
12
13
15
14
16
J23
pads on PCB
VDD_3V3_3U
ENSPI
NRST_3U
TDI_3U
TDO_3U
TCK_3U
TMS_3U
XIN_SAM3
TRESIN
TRESOUT
TRSTOUT
TRSTIN
GND
GND
150R
R251
150R
R252
150R
R254
VDDout
VDDout
DIS_CDC
DIS_JLINK
ENSPI
JLINK_UART_RX
JLINK_UART_TX
0.1uF
10V
0402
C256
JLINK_USBHS_N
JLINK_USBHS_P
JLINK_USBFS_N
JLINK_USBFS_P
STB 1
GND
2
OUT 3
VDD
4
12.00 MHz
Y10
EP 7
VIN
6
VOUT 1
GND 3
EN
4
NC
5
VOUT 2
MIC5528 3V3
U28
0402
R249
100R 0402
5%
R244
100R
0402
5%
R245
100R
0402
5%
R248
1k
0402
5%
R258
1k
0402
5%
R259
100k 0402 5%
R255
JLINK_TCK_IN
JLINK_TDI_IN
JLINK_TDO_IN
JLINK_TMS_IN
100R 0402
5%
R242
JLINK_NTRST
JLINK_nRST
XIN_SAM3
JLINK OB
150R
R243
51R
0402
1%
R262
120R
BLM18PG121SN1D
FB16
DIFF90
TP30
90
Ω
±15% differential trace impedance
Routing top or bottom
Table 3-46. J-Link-OB and J-Link-CDC LED D10 Status
LED D10
State
Description
Red and green
Off
J-Link (SAM3U device) is not programmed, or J25 and J26 are shorted.
Red
On
J-Link (SAM3U device) is programmed but J-Link is disabled (J26 shorted).
Green
Flashing
J-Link is operational but the USB port is not connected.
Green
On
J-Link-OB is connected and ready.
The ATSAM3U microcontroller (U26) is powered only through the J-Link USB connector. The programmer IC is
therefore separated from the rest of the system and the user can have a better reading of the power that the system
is drawing when interrogating the on-board power measurement devices.
The MIC5528 (U28) has been selected to convert the 5V coming from the USB connector into the 3.3V rail required
by the microcontroller. The MIC5528 is a simple low-power, low dropout regulator designed for optimal performance
in a very small footprint. It is capable of sourcing up to 500 mA of output current while only drawing 38 μA of
operating current. For more information about the MIC5528, refer to the product
.
SAMA7G54-EK
Function Blocks
©
2022 Microchip Technology Inc.
and its subsidiaries
User Guide
DS50003273A-page 62
