SBOSAL5 Data sheet

Table 7-1 lists the INA2227 registers. All register locations not listed in the table are considered as reserved locations and the register contents must not be modified.

Table 7-1 INA2227 Register Overview

Register Name	Address	Register Type	Register Size (bits)	Default Value
CONFIG1	0x10	R/W	16	0xF127
CONFIG2	0x11	R/W	16	0x0000
CALIBRATION_(CH1 - CH2)	0x05,0x0D	R/W	16	0x0000
ALERT_CONFIG(1 - 2)	0x07, 0x0F	R/W	16	0x0000
ALERT_LIMIT(1 - 2)	0x06, 0x0E	R/W	16	0x0000
SHUNT_VOLTAGE_(CH1 - CH2)	0x00, 0x08	R	16	0x0000
BUS_VOLTAGE_(CH1 - CH2)	0x01, 0x09	R	16	0x0000
CURRENT_(CH1 - CH2)	0x02, 0x0A	R	16	0x0000
POWER_(CH1 - Ch2)	0x03, 0x0B	R	16	0x0000
ENERGY_(CH1 - CH2)	0x04, 0x0C	R	32	0x0000
FLAGS	0x12	R	16	0x0000
MANUFACTURER_ID	0x7E	R	16	0x5449 ("TI" in ASCII)
DEVICE_ID	0x7F	R	16	0x2350

Complex bit access types are encoded to fit into small table cells. Table 7-2 shows the codes that are used for access types in this section.

Table 7-2 Device Access Type Codes

Access Type	Code	Description
Read Type
R	R	Read
Write Type
W	W	Write

7.1.1 CONFIG1 Register (Address = 0x10h)

The configuration register is shown in Table 7-3.

Table 7-3 CONFIG1 Register Field Descriptions

Bit	Field	Type	Reset	Description
15-12	ACTIVE_CHANNEL	R/W	0011b	These 4 bits determine which channels are active. Set this bit to '1' to enable each channel. Disabled channels are skipped in the round robin cycle. Bit15 = reserved. Bit14 = reserved. Bit13 = Channel 2 measurement enable/disable. Bit12 = Channel 1 measurement enable/disable. Power up default: 0011b = All channels active
11-9	AVG	R/W	000b	Sets the number of ADC conversion results to be averaged. The read-back registers are updated after averaging is completed. 000b = 1 001b = 4 010b = 16 011b = 64 100b = 128 101b = 256 110b = 512 111b = 1024
8-6	VBUSCT	R/W	100b	Sets the conversion time of the VBUS measurement 000b = 140µs 001b = 204µs 010b = 332µs 011b = 588µs 100b = 1100µs 101b = 2116µs 110b = 4156µs 111b = 8244µs
5-3	VSHCT	R/W	100b	Sets the conversion time of the SHUNT measurement 000b = 140µs 001b = 204µs 010b = 332µs 011b = 588µs 100b = 1100µs 101b = 2116µs 110b = 4156µs 111b = 8244µs
2-0	MODE	R/W	111b	Operating mode: Modes can be selected to operate the device either in Shutdown mode, continuous mode or triggered mode. The mode also allows user to select mux settings to set continuous or triggered mode on bus voltage and/or shunt voltage measurements. 000b = Shutdown 001b = Shunt voltage triggered, single shot 010b = Bus voltage triggered, single shot 011b = Shunt voltage and Bus voltage triggered, single shot 100b = Shutdown 101b = Continuous shunt voltage 110b = Continuous bus voltage 111b = Continuous shunt and bus voltage

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7.1.2 CONFIG2 Register (Address = 0x11h)

The configuration register is shown in Table 7-4.

Table 7-4 CONFIG2 Register Field Descriptions

Bit	Field	Type	Reset	Description
15	RST	R/W	0b	Set this bit to '1' to generate a system reset that is the same as power-on reset. Resets all registers to default values and then self-clears.
14-12	Reserved	R	000b	These bits always read 0.
11-8	ACC_RST	R/W	0000b	Writing a one to these bits resets the energy registers and clears any overflow flags. Bit11 = reserved. Bit10 = reserved. Bit9 = Channel 2 energy reset, overflow clear. Bit8 = Channel 1 energy reset, overflow clear. Power up default: 0000b = All channels active Bits are reset back to 0 after write.
7	CNVR_MASK	R/W	0b	Setting this bit high configures the ALERT pin to be asserted when conversions are complete. 0b = Disable conversion ready flag on ALERT pin 1b = Enables conversion ready flag on ALERT pin ALERT remains asserted until the CVRF field in the flags register is read.
6	ENOF_MASK	R/W	0b	When set to 1, the Alert pin toggles when an energy overflow condition occurs on any of the enabled channels
5	ALERT_LATCH	R/W	0b	When set to 1 the state of the Alert pin latches during fault conditions. To clear the alert the alert flags register must be read and the fault condition removed.
4	ALERT_POL	R/W	0b	When this bit is set to 1, the alert pin toggles from low to high during a fault condition. When set to 0 (default), the alert pin toggles from high to low during faults.
3-0	RANGE	R/W	0000b	Enables the selection of the shunt full scale input range for each channel. Bit3 = reserved. Bit2 = reserved. Bit1 = Channel 2 range selection. Bit0 = Channel 1 range selection. range selection bit = 0 selects ±81.92mV range selection bit = 1 selects ±20.48mV 0000b = all channels set to ±81.92mV range

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7.1.3 CALIBRATION Registers

The calibration registers shown in Table 7-5 must be programmed to receive valid current, power, and energy results after initial power up, power cycle events, or on device enable.

Table 7-5 INA2227 Calibration Registers

Address	Register Name	Register Type	Register Size (bits)
0x05	CALIBRATION_CH1	R/W	16
0x0D	CALIBRATION_CH2	R/W	16

This register provides the device with the value of the shunt resistor that are present to create the measured differential voltage. This register also sets the resolution of the Current Register. Programming this register sets the Current_LSB and the Power_LSB.

Table 7-6 Calibration Register Field Descriptions

Bit	Field	Type	Reset	Description
15	Reserved	R	0h
14-0	SHUNT_CAL	R/W	0000h	Programmed value needed for doing the shunt voltage to current conversion.

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7.1.4 Alert Configuration Registers

The alert configuration registers are shown in Table 7-7.

Table 7-7 INA2227 ALERT_CONFIG Registers

Address	Register Name	Register Type	Register Size (bits)
0x07	ALERT1	R/W	16
0x0F	ALERT2	R/W	16

The format of each alert configuration register is shown in Table 7-8.

These registers configure what triggers an alert for each of the channels. The alert mask field sets the active alert.

Table 7-8 Alert Configuration Register Field Descriptions

Bit	Field	Type	Reset	Description
15 - 4	Reserved	R	000000000000b	Reserved
4-3	CHANNEL	R/W	00b	Selects 00b = Channel 1 01b = Channel 2 10b = reserved. 11b = reserved.
2-0	ALERT_MASK	R/W	000b	Sets the active alert for the assigned channel 000b = reserved, no effect 001b = Shunt Voltage over limit (SOL) 010b = Shunt Voltage under limit (SUL) 011b = Bus Voltage over limit (BOL) 100b = Bus Voltage under limit (BUL) 101b = Power over limit (POL) 110b = reserved, no effect 111b = reserved, no effect

Bit

Field

Type

Reset

Description

15 - 4

Reserved

R

000000000000b

Reserved

4-3

CHANNEL

R/W

00b

Selects

00b = Channel 1

01b = Channel 2

10b = reserved.

11b = reserved.

2-0

ALERT_MASK

R/W

000b

Sets the active alert for the assigned channel

000b = reserved, no effect

001b = Shunt Voltage over limit (SOL)

010b = Shunt Voltage under limit (SUL)

011b = Bus Voltage over limit (BOL)

100b = Bus Voltage under limit (BUL)

101b = Power over limit (POL)

110b = reserved, no effect

111b = reserved, no effect

The alert configuration registers set what triggers an alert for each of the channels. The alert mask field sets the active alert. Up to 2 alerts can be assigned to a given channel or spread as required across all channels depending on the application.

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7.1.5 Alert Limit Registers

The alert limit registers shown in Table 7-9 must be programmed to set the desired fault limit threshold.

Table 7-9 INA2227 ALERT_LIMIT Registers

Address	Register Name	Register Type	Reset	Register Size (bits)
0x06	LIMIT1	R/W	0000h	16
0x0E	LIMIT2	R/W	0000h	16

The format of the alert limit register follows the format of the corresponding result register.

Shunt voltage limits are represented as signed 16 bit, bus voltage limits are unsigned 15 bit, and power limits are unsigned 16 bit values.

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7.1.6 Shunt Voltage Registers

The Shunt Voltage Registers store the current shunt voltage reading, V_SHUNT. The shunt voltage measurement for each channel has a unique address as shown in Table 7-10.

Table 7-10 INA2227 SHUNT_VOLTAGE Registers

Address	Register Name	Register Type	Register Size (bits)
0x00	SHUNT_VOLTAGE_CH1	R	16
0x08	SHUNT_VOLTAGE_CH2	R	16

The format of each shunt voltage register is shown in Table 7-11.

If averaging is enabled, these registers contain the averaged shunt voltage value.

Table 7-11 Shunt Voltage Register Field Description

Bit	Field	Type	Reset	Description
15-0	VSHUNT	R	0000h	Differential voltage measured across the shunt output. 2's complement value.

Negative numbers are represented in two's complement format. Generate the two's complement of a negative number by complementing the absolute value binary number and adding 1. An MSB = '1' denotes a negative number.

Example: For a value of V_SHUNT = –80mV:

Take the absolute value: 80mV
Translate this number to a whole decimal number (80mV ÷ 2.5µV) = 32000
Convert this number to binary = 0111 1101 0000 0000
Complement the binary result = 1000 0010 1111 1111
Add '1' to the complement to create the two's complement result = 1000 0011 0000 0000 = 8300h

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7.1.7 Bus Voltage Registers

The bus voltage registers store the voltage measured at the bus pin for each of the channels. Bus voltage measurements are stored in an unique register addresses as shown in Table 7-12.

Table 7-12 INA2227 BUS_VOLTAGE Registers

Address	Register Name	Register Type	Register Size (bits)
0x01	BUS_VOLTAGE_CH1	R	16
0x09	BUS_VOLTAGE_CH2	R	16

The format of each bus voltage register is shown in Table 7-13.

The bus voltage registers only return positive values. If averaging is enabled, this register displays the averaged value.

Table 7-13 BUS_VOLTAGE Register Field Description

Bit	Field	Type	Reset	Description
15-0	VBUS	R	0000h	Bus voltage output. 2's complement value, however always positive.

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7.1.8 CURRENT Registers

The current registers store the calculated current value for each of the channels. Current measurements are stored in an unique register addresses as shown in Table 7-14.

Table 7-14 INA2227 CURRENT Registers

Address	Register Name	Register Type	Register Size (bits)
0x02	CURRENT_CH1	R	16
0x0A	CURRENT_CH2	R	16

The format of each current register is shown in Table 7-15.

If averaging is enabled, this register displays the averaged value. The value of the Current Register is calculated by multiplying the decimal value in the Shunt Voltage Register with the decimal value of the Calibration Register.

Table 7-15 CURRENT Register Field Description

Bit	Field	Type	Reset	Description
15-0	CURRENT	R	0000h	Calculated current output in Amperes. 2's complement value.

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7.1.9 POWER Registers

The power registers store the multiplied value of the bus voltage and current for each of the channels. Power measurements are stored in an unique register addresses as shown in Table 7-16.

Table 7-16 INA2227 POWER Registers

Address	Register Name	Register Type	Register Size (bits)
0x03	POWER_CH1	R	16
0x0B	POWER_CH2	R	16

The format of each power register is shown in Table 7-17.

If averaging is enabled, this register displays the averaged value. The Power Register records power in Watts by multiplying the decimal values of the Current Register with the decimal value of the Bus Voltage Register. This is an unsigned result.

Table 7-17 POWER Register Field Description

Bit	Field	Type	Reset	Description
15-0	POWER	R	0000h	This bit returns a calculated value of power in the system. This is an unsigned result.

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7.1.10 Energy Registers

The energy registers accumulate data from the power registers and with the internal precision timebase calculate and store the energy for each of the channels. Energy measurements are stored in an unique register addresses as shown in Table 7-18.

Table 7-18 INA2227 ENERGY Registers

Address	Register Name	Register Type	Register Size (bits)
0x04	ENERGY_CH1	R	32
0x0C	ENERGY_CH2	R	32

The format of each energy register is shown in Table 7-19.

The Energy register records energy in Joules and utilizes the precision oscillator as a timebase. This is an unsigned result.

Table 7-19 Energy Register Field Description

Bit	Field	Type	Reset	Description
31-0	ENERGY	R	00000000h	This bit returns a calculated value of energy in the system. This is an unsigned result.

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7.1.11 Flags Register

The Flags Register is shown in Table 7-20.

Table 7-20 Flags Register Field Descriptions

Bit	Field	Type	Reset	Description
15	Reserved	R	0b	Reserved, returns 0.
14	Reserved	R	0b	Reserved, returns 0.
13	LIMIT2_ALERT	R	0b	Indicates the second alert limit has been exceeded. This alert is independent of channel.
12	LIMIT1_ALERT	R	0b	Indicates the first alert limit has been exceeded. This alert is independent of channel.
11	Reserved	R	0b	Reserved, returns 0.
10	Reserved	R	0b	Reserved, returns 0.
9	ENERGYOF_CH2	R	0b	Indicates an the energy register has overflowed for channel 2
8	ENERGYOF_CH1	R	0b	Indicates an the energy register has overflowed for channel 1
7	CVRF (Conversion Ready Flag)	R	0b	Although the device can be read at any time, and the data from the last conversion is available, the Conversion Ready Flag bit is provided to help coordinate one-shot or triggered conversions. The Conversion Ready Flag bit is set after all conversions, averaging, and multiplications are complete. Conversion Ready Flag bit clears under the following conditions: 1.) Writing to the Config1 Register (except for Power-Down selection) 2.) Reading the Flags Register
6	OVF (Math Over-flow)	R	0b	This bit is set to '1' if an arithmetic operation results in an overflow error. This bit indicates that current and power data can be invalid.
5-0	Reserved	R	000000b	Reserved, returns 0.

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7.1.12 Manufacturer ID Register (Address = 7Eh)

The manufacturer ID register is shown in Table 7-21.

Table 7-21 MANUFACTURE_ID Register Field Descriptions

Bit	Field	Type	Reset	Description
15-0	MANUFACTURE_ID	R	5449h	Reads back TI in ASCII

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7.1.13 Device Identification Register (Address = 7Fh)

The DEVICE_ID register is shown in Table 7-22.

Table 7-22 DEVICE_ID Register Field Descriptions

Bit	Field	Type	Reset	Description
15-4	DIE_ID	R	0x235	Stores the device identification bits
3-0	REV_ID	R	0h	Device revision identification.

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Package Options

Mechanical Data (Package|Pins)

Thermal pad, mechanical data (Package|Pins)

Orderable Information

7.1 Device Registers

7.1.1 CONFIG1 Register (Address = 0x10h)

7.1.2 CONFIG2 Register (Address = 0x11h)

7.1.3 CALIBRATION Registers

7.1.4 Alert Configuration Registers

7.1.5 Alert Limit Registers

7.1.6 Shunt Voltage Registers

7.1.7 Bus Voltage Registers

7.1.8 CURRENT Registers

7.1.9 POWER Registers

7.1.10 Energy Registers

7.1.11 Flags Register

7.1.12 Manufacturer ID Register (Address = 7Eh)

7.1.13 Device Identification Register (Address = 7Fh)