11.4.7 Power; Signal Characteristics; 11.5.1 Ready Led Out - Seagate 1200 SSD Product Manual

11.4.7 Power

The drive receives power (+3.3 volts, +5 volts and +12 volts) through the SAS device connector.
Three +12 volt pins provide power to the drive, 2 short and 1 long. The current return for the +12 volt power supply is through
the common ground pins. The supply current and return current must be distributed as evenly as possible among the pins.
Three +5 volt pins provide power to the drive, 2 short and 1 long. The current return for the +5 volt power supply is through
the common ground pins. The supply current and return current must be distributed as evenly as possible among the pins.
Two +3.3 volt pins provide power to the drive, 1 short and 1 long. The current return for the +3.3 volt power supply is through
the common ground pins. The supply current and return current must be distributed as evenly as possible among the pins.
Current to the drive through the long power pins may be limited by the system to reduce inrush current to the drive during hot
plugging.
11.5 S
IGNAL CHARACTERISTICS
This section describes the electrical signal characteristics of the drive's input and output signals. See Table 23 for signal type
and signal name information.

11.5.1 Ready LED Out

The Ready LED Out signal is driven by the drive as indicated in Table 25.
Table 25 Ready LED Out conditions
N
ORMAL COMMAND ACTIVITY
Ready LED Meaning bit mode page 19h
Drive stopped, not ready, and no activity
Drive stopped, not ready, and activity
(command executing)
Drive started, ready, and no activity
Drive started, ready, and activity
(command executing)
Drive transitioning from not-ready state to
ready state or the reverse.
FORMAT UNIT in progress,
The Ready LED Out signal is designed to pull down the cathode of an LED. The anode is attached to the proper +3.3 volt
supply through an appropriate current limiting resistor. The LED and the current limiting resistor are external to the drive. See
Table 26 for the output characteristics of the LED drive signals.
Table 26 LED drive signal
S
TATE
LED off, high
LED on, low
S 1200 SSD P
EAGATE RODUCT
LED
STATUS
(50% on and 50% off, 0.5 seconds on and off for 0.5 seconds)
T
EST CONDITION
≤ ≤
0 V VOH 3.6 V
I = 15 mA
OL
M , R . A
ANUAL EV
0
Off
On
On
Off
Blinks steadily
Toggles on/off
O
UTPUT VOLTAGE
-100 μA < I < 100 μA
OH
≤ ≤
0 V 0.225 V
OL
1
Off
On
Off
On
70