HDMP-1685A Datasheet, PDF (14/21 Pages) Agilent(Hewlett-Packard) – 1.25 Gbps Four Channel SerDes with 5-pin DDR SSTL-2 Parallel Interface

Filtering Schematic
0.1 µF
V_CC
+
10 µF ^*
0.1 µF
0.1 µF
0.1 µF
0.1 µF
C4 _VCR
C5 _VCR
D3 _VCR
F3 _VCR
G4 _VCC
L4 _VCC
R4 _VCC
HDMP-1685A
GUIDELINES FOR
DECOUPLING CAPACITOR
PLACEMENTS/CONNECTIONS
VCR ^C11
V_CC ^C14
VCR ^C15
VCR ^E14
VCR ^G17
V_CC ^J14
V_CC ^K16
V_CC ^N15
V_CC ^R16
0.1 µF
0.1 µF
0.1 µF
0.1 µF
V_CC
0.1 µF
0.1 µF
0.1 µF
0.1 µF
1 µH
+
+
10 µF 10 µF
+
0.1 µF
* ^{PLACEMENT NOT CRITICAL. INDICATES}
THE NEED FOR ADDITIONAL LOW FREQUENCY
CAPACITIVE DECOUPLING.
+ OPTIONAL – PROVIDES INCREASED LOW
FREQUENCY DECOUPLING.
01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17
0.1 µF
0.1 µF
10 µF*
0.1 µF
A GND V_CC GND
B
GND
VCR
VCR V_CC GND
GND
VCR
GND VCR GND
C
VCR VCR
GND
D
VCR GND GND
VCR
GND
V_CC VCR GND
E
0.1 µF
F
VCR GND
VCR GND
GND
G
GND V_CC
H
* 10 µF PLACEMENT NOT CRITICAL – INDICATES
NEED FOR LOW-FREQUENCY BYPASS CAPACITANCE
VCR
J
V_CC
K
GND GND
L
GND V_CC
HDMP-1685A
GND GND V_CC
M
N
0.1 µF
V_CC
P
GND
GND
GND
GND
GND
R
GND V_CC
GND
GND
GND
GND
V_CC GND V_CC
T
GND V_CC V_CC VCP GND VCP GND V_CCA GND VCP GND VCP V_CC GND GND
U GND GND
V_CC
GND GND
GND
GND GND GND
0.1 µF
0.1 µF
0.1 µF
0.1 µF
10 µF
TO V_CCA PI-FILTER (SEE SCHEMATIC)
13