SBOSA81D may 2021 – august 2023 INA236
PRODUCTION DATA
Refer to the PDF data sheet for device specific package drawings
The INA236 operates only as a target on both the SMBus and I2C interfaces. Connections to the bus are made through the open-drain SDA and SCL lines. The SDA and SCL pins feature integrated spike suppression filters and Schmitt triggers to minimize the effects of input spikes and bus noise. Although the device integrates spike suppression into the digital I/O lines, proper layout techniques help minimize the amount of coupling into the communication lines. This noise introduction could occur from capacitive coupling signal edges between the two communication lines themselves or from other switching noise sources present in the system. Routing traces in parallel with ground in between layers on a printed circuit board (PCB) typically reduces the effects of coupling between the communication lines. Shielded communication lines reduce the possibility of unintended noise coupling into the digital I/O lines that could be incorrectly interpreted as start or stop commands.
The INA236 supports the transmission protocol for fast mode up to 400 kHz and high-speed mode up to 2.94 MHz. All data bytes are transmitted most significant byte first and follow the SMBus 3.0 transfer protocol.
To communicate with the INA236, the controller must first address targets through a target address byte. The target address byte consists of seven address bits and a direction bit that indicates whether the action is to be a read or write operation.
The INA236 uses a single address pin, A0. Table 7-1 shows possible configurations for A0 and the corresponding address for both the A and B versions of the device. The INA236 samples the state of the A0 pin on every bus communication. The pin state for A0 must be established before any activity on the interface occurs. When connecting the SDA pin to A0 to set the device address, make sure to add an additional hold time of 100 ns on the MSB of the I2C address to ensure correct device addressing. The A and B device options, each with four unique addresses, allows users to connect up to eight devices in a system without I2C address conflicts.
A0 | INA236A DEVICE OPTION | INA236B DEVICE OPTION |
---|---|---|
GND | 1000000 | 1001000 |
VS | 1000001 | 1001001 |
SDA | 1000010 | 1001010 |
SCL | 1000011 | 1001011 |