L6701 datasheet(17/44 Pages) STMICROELECTRONICS

17 / 44 page

L6701

7 Configuring the Device: DAC Selection

17/44

Configuring the Device: DAC Selection

Multiple DACs need to be configured before the system start-up by programming the apposite

pin DAC_SEL. The embedded DAC allows to regulate the output voltage with a tolerance of

±0.7% recovering from offsets and manufacturing variations. In case of selecting VR9 and

VR10 Mode, the device automatically introduces a -19mV offset to the regulated voltage (see

Table 5 and Table 6) in order to avoid any external offset circuitry to worsen the guaranteed

accuracy and, as a consequence, the calculated system TOB. In case of selecting the K8 DAC,

VID5 gives the option to introduce +25mV offset to the regulation (See Table 7).

Output voltage is programmed through the VID pins: they are inputs of an internal DAC that is

realized by means of a series of resistors providing a partition of the internal voltage reference.

The VID code drives a multiplexer that selects a voltage on a precise point of the divider. The

DAC output is delivered to an amplifier obtaining the voltage reference available on REF_OUT.

According to the selected DAC, the device also changes the protection thresholds as a

consequence of different CPU specifications, see Table 8 for details.

7.1

Single-Wire CPU Automatic Detection

L6701 has been designed to automatically detect the Intel CPU connected by monitoring the

DAC_SEL pin status at the start-up so modifying the DAC table accordingly (see Table 8). In

fact, by directly connecting the DAC_SEL pin with #BOOTSEL pin of the CPU, the controller

automatically recognize the different technology steps of the CPU so modifying the DAC table

accordingly.

See CPU related documentation for further details about compatibility.

Table 8.

L6701 Configuration

DAC_SEL

OPERATIVE MODE

OVP & Pre-

OVP

UVP

PGOOD

OPEN

AMD K8 +25mV (Driven by VID5)

1.9V Fixed

-400mV

-230mV

82k

Ω to GND

Intel VR10 -19mV

1.9V Fixed

-400mV

SSEND

GND

Intel VR9 -19mV

2.1V Fixed

-400mV

-230mV

L6701 bảng dữ liệu(PDF) 17 Page - STMicroelectronics

L6701 bảng dữ liệu(HTML) 17 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44

bảng dữ liệu tải về

Link URL