INA228-Q1

Part: INA228AIDGSR — Texas Instruments

Type: Digital Power/Energy/Charge Monitor (I²C, 20-bit delta-sigma ADC)

Description: 85 V common-mode, 20-bit ultra-precise current/voltage/power/energy/charge monitor with ±1 μV max shunt offset, ±0.05% max gain error, and I²C interface up to 2.94 MHz, powered from 2.7–5.5 V.

Operating Conditions:

• Supply voltage: 2.7–5.5 V
• Operating temperature: -40 to +125 °C
• Common-mode input range: -0.3 to 85 V
• Bus voltage input range: 0 to 85 V

Absolute Maximum Ratings:

• Max supply voltage: 6 V
• Max differential input (VIN+ − VIN-): ±40 V
• Max common-mode / VBUS voltage: 85 V
• Max input current into any pin: 5 mA
• Max junction temperature: 150 °C
• Storage temperature: -65 to 150 °C

Key Specs:

• Shunt offset voltage: ±0.3 μV typ, ±1 μV max (VCM = 48 V, TCT > 280 μs)
• Shunt offset drift: ±2 nV/°C typ, ±10 nV/°C max (-40 to +125 °C)
• Shunt gain error: ±0.01% typ, ±0.05% max; gain drift ±20 ppm/°C max
• CMRR: 154 dB min, 170 dB typ (-0.3 V < VCM < 85 V, -40 to +125 °C)
• Power total measurement error: ±0.5% max at full scale (-40 to +125 °C); energy and charge ±1% max
• Shunt full-scale range: ±163.84 mV (ADCRANGE = 0) / ±40.96 mV (ADCRANGE = 1)
• Input bias current: 0.1 nA typ, 2.5 nA max (VCM = 85 V)
• Temperature sensor accuracy: ±1 °C max at 25 °C; ±2 °C max over -40 to +125 °C
• Quiescent current: 640 μA typ, 750 μA max (25 °C); 1.1 mA max over -40 to +125 °C; shutdown 2.8 μA typ, 5 μA max
• ADC conversion time: 50 μs to 4120 μs; internal oscillator tolerance ±0.5% at 25 °C (±1% over temperature)

Features:

• 20-bit delta-sigma ADC
• Reports current, bus voltage, temperature, power, energy and charge
• Fast alert response: 75 μs
• Programmable resistor temperature compensation
• Programmable conversion time (50 μs to 4.12 ms) and averaging (1x to 1024x)
• 2.94 MHz high-speed I²C interface with 16 pin-selectable addresses
• Integrated temperature sensor

Applications:

• DC/DC converters and power inverters
• Industrial battery packs
• Power-over-Ethernet (PoE)
• Telecom equipment
• Enterprise servers

Package:

• VSSOP-10 (DGS), 3.00 mm × 3.00 mm

• High-resolution, 20-bit delta-sigma ADC
• Current monitoring accuracy:
• -Offset voltage: ±1 μV (maximum)
• -Offset drift: ±0.01 μV/°C (maximum)
• -Gain error: ±0.05% (maximum)
• -Gain error drift: ±20 ppm/°C (maximum)
• -Common mode rejection: 154 dB (minimum)
• Power monitoring accuracy:
• -0.5% full scale, -40°C to +125°C (maximum)
• Energy and charge accuracy:
• -1.0% full scale (maximum)
• Fast alert response: 75 μs
• Wide common-mode range: -0.3 V to +85 V
• Bus voltage sense input: 0 V to 85 V
• Shunt full-scale differential range: ±163.84 mV / ±40.96 mV
• Input bias current: 2.5 nA (maximum)
• Temperature sensor: ±1°C (maximum at 25°C)
• Programmable resistor temperature compensation
• Programmable conversion time and averaging
• 2.94-MHz high-speed I 2 C interface with 16 pinselectable addresses
• Operates from a 2.7-V to 5.5-V supply:
• -Operational current: 640 μA (typical)
• -Shutdown current: 5 μA (maximum)

• DC/DC converters and power inverters
• Industrial battery packs
• Power-over-ethernet (PoE)
• Telecom equipment
• Enterprise servers

Figure 5-1. DGS Package 10-Pin VSSOP Top View

Table 5-1. Pin Functions

at T A = 25 °C, V S = 3.3 V, V SENSE = VIN+ - VIN- = 0 V, V CM = V IN- = 48 V (unless otherwise noted)

over operating free-air temperature range (unless otherwise noted) (1)

• (2) VIN+ and VIN- are the voltages at the IN+ and IN- pins, respectively.

over operating free-air temperature range (unless otherwise noted)

The low offset voltage and low input bias current of the INA228 allow accurate monitoring of a wide range of currents. To accurately monitor currents with high resolution, select the value of the shunt resistor so that the resulting sense voltage is close to the maximum allowable differential input voltage range (either ±163.84 mV or ±40.96 mV, depending on register settings). The circuit for monitoring currents in a high-side configuration is shown in Figure 8-2.

Figure 8-2. INA228 High-Side Sensing Application Diagram