ISL62776IRTZ datasheet(32/50 Pages) RENESAS

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ISL62776

6. Telemetry

R16DS0044EU0200 Rev.2.00

Page 32 of 49

Oct.8.20

Telemetry

The ISL62776 can provide voltage and current information to the AMD processor through the telemetry system

outlined by the AMD SVI 2.0 specification. The telemetry data is transmitted through the SVC and SVT lines of the

SVI 2.0 interface.

Current telemetry is based on a voltage generated across the recommended 133kΩ resistor placed from the

IMON pin to GND. The current flowing out of the IMON pin is proportional to the load current in the VR. The Isum

current defined in Voltage Regulation and Load Line Implementation provides the base conversion from the load

current to the Isum current created by the internal amplifier. The Isum current is then divided down by a factor of 4

to create the IMON current, which flows out of the IMON pin. The Isum current measures 36µA when the load

current is at full load based on a droop current designed for 45µA at the same load current. The difference

between the Isum current and the droop current is provided in Equation 2. The IMON current measures 11.25µA at

full load current for the VR and the IMON voltage is 1.2V. The load percentage reported by the IC is based on the

this voltage. When the load is 25% of the full load, the voltage on the IMON pin is 25% of 1.2V or 0.3V.

The SVI interface allows the selection of no telemetry, voltage only, or voltage and current telemetry on either or

both of the VR outputs. The processor uses the TFN bit and the Core and SOC domain selector bits to change the

telemetry functionality. See Table 10 for more information.

Table 10. TFN Truth Table

TFN, Core, SOC

Bits [21, 6, 7]

Description

1, 0, 1

Telemetry is in voltage and current mode, so the voltage and current are sent for the VDD and VDDSOC

domains by the controller.

1, 0, 0

Telemetry is in voltage mode only. The controller sends only the voltage of VDD and VDDSOC domains.

1, 1, 0

Telemetry is disabled.

1, 1, 1

Reserved

ISL62776IRTZ Datasheet(PDF) 32 Page - Renesas Technology Corp