PM6652 STMicroelectronics, PM6652 Datasheet - Page 25

• Manufacturer Part Number: PM6652
• Description: IC CTLR STEPDOWN SMPS 32VFQFPN
• Manufacturer: STMicroelectronics

Specifications of PM6652

• Applications: Controller, Intel IMVP-6.5™, VR11
• Voltage - Input: 4.5 V ~ 36 V
• Number Of Outputs: 1
• Voltage - Output: 0.3 V ~ 1.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 32-VFQFN Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

PM6652
8
8.1
Device description
The PM6652 is a single phase, step-down controller which can be easily configured to
regulate power to IMPV6.5 and VR11 devices, as listed below:
●
●
●
The supply mode and platform compliance are selected by acting on two multi-function pins
(refer to
The PM6652 is based on constant on-time control architecture. This type of control offers a
very fast load transient response with a minimum external component count. A typical
application circuit is shown in
analog converter (DAC) that provides a reference voltage according with the VID pins
settings (see
droop) control, proportional to the inductor DCR or dedicated precision resistor, according to
IMVP6.5 specifications.
The switching frequency can be programmed in the range 200 kHz up to 600 kHz with an
external resistor connected to the input voltage (see
control
In order to maximize the efficiency at very light load, a pulse skipping control algorithm is
performed. The PM6652 is also fully compliant with the fast and slow render suspend state
exit mode, as required by IMVP 6.5 spec. for render core supply (see
dynamic (VID) transitions on page 30
The device provides protection versus overvoltage, undervoltage, overcurrent and
overtemperature as well as power good (PWRGD), current monitor (IMON) and thermal
throttling (VRTT#) signals for monitoring purposes. The clock enable output signal
(CLKEN#), for appropriate platform power-up, is available in CPU supply mode only.
Constant on time PWM control
The PM6652 controller uses a pseudo-fixed frequency, Constant On-Time (COT) controller
as the core of the switching section. The COT controller uses a relatively simple algorithm,
exploiting the ripple voltage due to inductor resistance DCR (or due to a sense resistor
R
Nearly constant switching frequency is achieved by the system loop in steady-state
operating conditions, avoiding thus the need for a clock generator. A slight switching
frequency variation vs the load is the consequence of the switching regulator power losses,
which implies the off-time duration decrease.
The on-time one shot duration is directly proportional to the output voltage, sensed at VOUT
pin, and inversely proportional to the input voltage, sensed at the VOSC pin, as follows:
SNS
The graphics (Render) core of the Intel
platform;
The low voltage and ultra low voltage mobile CPU, used on Calpella platform;
The VR11 compliant CPU, like Intel® ATOM 200/300 and Pineview-D CPU.
) to trigger the fixed on-time one-shot generator.
for details).
Section 8.2: Mode selection on page 28
Table 6
and
Table
Figure 1 on page
Doc ID 16867 Rev 3
7). The PM6652 also allows adjusting an active load line (or
for details).
®
mobile Arrandale processor used on Calpella
7. The controller includes a 7 bit digital-to-
for details), before the device turn-on.
Section 8.1: Constant on time PWM
Section 8.6: Voltage
Device description
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