ISL6111 Datasheet, PDF (10/16 Pages) Intersil Corporation – Current Regulated PCI Hot Plug Power Switch Controller

ISL6111
parasitic inductance and resistance effects, maximize the
width of the high-current PCB traces.
CORRECT
INCORRECT
ISL6111 is simply grounded. The Fault-not output, FLTN
pulls low once the CR duration has expired and signals that
all supplies have been disconnected from the load. See
Figure 3 for operational PGOOD and FLTN waveforms.
PGOOD / FLTN 5/DIV
TO ISL6111
VS AND VISEN
TO ISL6111
VS AND VISEN
CURRENT
SENSE RESISTOR
FIGURE 2. SENSE RESISTOR PCB LAYOUT
PGOOD vs Power is Good and Fault Signals
Keep in mind that the -12VOUT is not monitored for under
voltage, thus the PGOOD output signal only takes into
account the three positive supplies. PGOOD will assert once
all minimum positive UV criteria is reached and the M12VO
may not be more than a few volts below ground at that time.
It will pull low once any positive voltage < UV Vth. For
applications that don't use -12V, the M12VI pin on the
5IOUT 5A/DIV CR = 7.2A
5VOUT 2/DIV
CRTIM 2V/DIV
20ms/DIV
FIGURE 3. FLTN & PGOOD FUNCTIONAL WAVEFORM
Adjusting the Current Regulation Level
The current regulation level is adjusted by the CRSET
resistance to ground value. The ratio of resistance to CR
change is not linear but is unidirectional in relationship, see
Figures 4-6.
Typical Performance Curves & Waveforms
12
10
85°C
8
3.3V
6 25°C
5V
4
0°C
2
0
3
3.5
4
4.5
R_CRSET (kΩ)
FIGURE 4. 3.3V & 5V SLOWLY INCREASING CURRENT TRIP
LEVEL vs TEMPERATURE AND RCRSET
0.6
85°C
0.5
+12V
0.4
0°C
0.3
25°C
0.2
0.1
-12V
0
3
3.5
4
4.5
R_CRSET (kΩ)
FIGURE 5. +12V & -12V SLOWLY INCREASING CURRENT
TRIP LEVEL vs TEMPERATURE AND RCRSET
10