C
HEETAH
15K.7 FC P
RODUCT
M
ANUAL
, R
EV
. E
58
11.5.4 Pin descriptions
This section provides a pin-out of the FC-SCA and a description of the functions provided by the pins.
Table 24 FC-SCA pin descriptions
P
I
N
S
IGNAL NAME
S
IGNAL TYPE
P
IN
S
IGNAL NAME
S
IGNAL TYPE
1*
-EN bypass port A
Low Voltage TTL out-
put
21
12 Volts charge
2*
12 Volts
22
Ground
3*
12 Volts
23
Ground
4*
12 Volts
24*
+Port A_in
FC Diff. input pair
5*
-Parallel ESI
25*
-Port A_in
6*
Ground
[1]
26
Ground
7*
Active LED out
Open collector out
27*
+Port B_in
FC Diff. input pair
8*
Reserved
28*
-Port B_in
9*
Start_1
[2]
TTL input
29
Ground
10
*
Start_2
[2]
TTL input
30*
+Port A_out
FC Diff. output pair
11
*
-EN bypass port B
Low Voltage TTL out-
put
31*
-Port A_out
12
*
SEL_6
TTL input/output
32
Ground
13
*
SEL_5
TTL input/output
33*
+Port B_out
FC Diff. output pair
14
*
SEL_4
TTL input
34*
-Port B_out
15
*
SEL_3
TTL input/output
35
Ground
16
*
Fault LED out
Open collector out
36
SEL_2
TTL input/output
17
*
DEV_CTRL_CODE_2
[
2]
TTL input
37
SEL_1
TTL input/output
18
*
DEV_CTRL_CODE_1
[
2]
TTL input
38
SEL_0
TTL input/output
19
*
5 Volts
39
DEV_CTRL_CODE_0
[
2
TTL input
20
*
5 Volts
40
5 Volts charge
*Short pins in mating backpanel connector.
[1] This pin may be connected to external logic to detect the presence of the drive. The drive connects this pin to the com-
mon ground.
[2] Pins 9, 10, 17, 18, and 39 are option select pins and are tied high by the drive circuitry. The preferred electrical connec-
tion at the backplane is either open or grounded (open for the ‘1’ setting, grounded for the ‘0’ setting). Alternatively,
these pins may be driven by a 3.3V logic device, pulled up to 3.3V through a pull-up resistor (recommended size of 10k
ohm), or grounded through some other means.
