HIP6502BCB Intersil Corporation, HIP6502BCB Datasheet - Page 8

• Manufacturer Part Number: HIP6502BCB
• Description: Multiple Linear Power Controller with ACPI Control Interface
• Manufacturer: Intersil Corporation

Not shown in these diagrams is the deglitching feature used
to protect against false sleep state tripping. Both S3 and S5
pins are protected against noise by a 2 s filter (typically 1 -
4 s). This feature is useful in noisy computer environments if
the control signals have to travel over significant distances.
Additionally, the S3 pin features a 200 s delay in
transitioning to sleep states. Once the S3 pin goes low, an
internal timer is activated. At the end of the 200 s interval, if
the S5 pin is low, the HIP6502B switches into S5 sleep state;
if the S5 pin is high, the HIP6502B goes into S3 sleep state.
Soft-Start Circuit
SOFT-START INTO SLEEP STATES (S3, S4/S5)
The 5VSB POR function initiates the soft-start sequence. An
internal 10 A current source charges an external capacitor.
The error amplifiers reference inputs are clamped to a level
INTERNAL
3V3DLSB
VSEN1, 2
DEVICES
5VDLSB
FIGURE 5. 5V
FIGURE 6. 2.5V
5V, 12V
5V, 12V
3V3DL
VSEN2
VSEN1
5VSB
5VDL
VCLK
5VSB
DRV2
3.3V,
DLA
3.3V,
DLA
S3
S5
S3
S5
3V
DIAGRAM; MSEL FLOATING (NOT CONNECTED)
DUAL
DUAL
MEM
/3V
TIMING DIAGRAM FOR EN5VDL = 0;
, 3.3V
SB
MEM
8
, AND 2.5V
CLK
TIMING
HIP6502B
proportional to the SS (soft-start) pin voltage. As the SS pin
voltage slews from about 1.25V to 2.5V, the input clamp
allows a rapid and controlled output voltage rise.
Figure 7 shows the soft-start sequence for the typical
application start-up in sleep state with all output voltages
enabled. At time T0 5VSB (bias) is applied to the circuit. At
time T1 the 5VSB surpasses POR level. An internal fast
charge circuit quickly raises the SS capacitor voltage to
approximately 1V, then the 10 A current source continues
the charging. The soft-start capacitor voltage reaches
approximately 1.25V at time T2, at which point the
3.3V
transition, causing the output voltage to ramp up
proportionally. The ramp-up continues until time T3 when the
3.3V
output reached its set value, as the soft-start capacitor
voltage reaches approximately 2.75V, the under-voltage
monitoring circuit of this output is activated and the soft-start
capacitor is quickly discharged to approximately 1.25V.
Following the 3ms (typical) time-out between T3 and T4, the
MSEL and EN5VDL selections are latched in, and the soft-
start capacitor commences a second ramp-up designed to
smoothly bring up the remainder of the voltages required by
the system. At time T5 all voltages are within regulation
limits, and as the SS voltage reaches 2.75V, all the
remaining UV monitors are activated and the SS capacitor is
quickly discharged to 1.25V, where it remains until the next
transition.
0V
0V
FIGURE 7. SOFT-START INTERVAL IN A SLEEP STATE
DUAL
DUAL
T0
VOLTAGES
OUTPUT
(1V/DIV)
T1 T2
/3.3V
/3.3V
V
(1V/DIV)
(ALL OUTPUTS ENABLED)
OUT3
5VSB
SB
SB
error amplifier’s reference input starts its
voltage reaches the set value. After this
(3.3V
T3
DUAL
SOFT-START
(1V/DIV)
/3.3V
TIME
T4
SB
)
T5
V
(2.5V
V
OUT5
OUT1
V
OUT2
MEM
(5V
(3.3V
)
DUAL
(2.5V
MEM
V
OUT4
)
)
CLK
)