L6756D STMicroelectronics, L6756D Datasheet - Page 23

• Manufacturer Part Number: L6756D
• Description: IC CTLR 2/3/4PH BUCK 40-VFQFPN
• Manufacturer: STMicroelectronics

Specifications of L6756D

• Applications: Controller, Intel VR10, VR11, VR11.1
• Voltage - Input: 12V
• Number Of Outputs: 4
• Voltage - Output: 0.3 ~ 1.6 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 40-VFQFN, 40-VFQFPN
• Output Voltage: 3 V
• Input Voltage: - 0.3 V to + 15 V
• Switching Frequency: 185 KHz to 215 KHz
• Operating Temperature Range: - 40 C to + 150 C
• Mounting Style: SMD/SMT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

L6756D
5.5
Caution:
Caution:
Dynamic VID transitions
L6756D manages dynamic VID transitions that allow the output voltage to modify during
normal device operation for CPU power management purposes. OV and UV signals are
properly masked during every DVID Transition and they are re-activated with a 16 clock
cycle delay to prevent from false triggering.
When changing dynamically the regulated voltage (DVID), the system needs to charge or
discharge the output capacitor accordingly. This means that an extra-current I
be delivered (especially when increasing the output regulated voltage) and it must be con-
sidered when setting the over current threshold of both the sections. This current results:
where dV
Dynamic VID transition is managed by checking for VID code modifications (See
on the rising edge of an internal additional DVID-clock and waiting for a confirmation on the
following falling edge. Once the new code is stable, on the next rising edge, the reference
starts stepping up or down in LSB increments every two DVID-clock cycle until the new VID
code is reached.
DVID-clock frequency (F
Overcoming the OC threshold during the DVID causes the device latch and disable.
If the new VID code is more than 1 LSB different from the previous, the device will execute
the transition stepping the reference with the DVID-clock frequency F
has reached. The output voltage rate of change will be of [LSB]mV * F
Figure 8.
I
DVID
=
C
OUT
OUT
DVID transitions
⋅
/ dT
dV
----------------- -
dT
OUT
VID
VID
depends on the operative mode (typically externally driven).
DVID
) is 1 MHz (Typ).
Output voltage positioning
DVID
DVID
until the new code
!
DVID
Figure
needs to
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8)