SLLSEY7F June 2017 – April 2020 ISO1211 , ISO1212
PRODUCTION DATA.
Refer to the PDF data sheet for device specific package drawings
The ISO121x devices are suitable for 48-V digital input receivers. The current limit, voltage transition thresholds, and maximum voltage supported at the module input are governed by Equation 1, Equation 2, Equation 3, and Equation 4. For 48-V systems, a threshold voltage close to 25 V is desirable. The RTHR resistor can be adjusted to achieve this higher threshold. For example, with an RSENSE value of 562 Ω and an RTHR value of 7.5 k Ω, a VIH value of approximately 25 V can be achieved. With this setting, the RTHR resistor drops a voltage of approximately 17 V, reducing the maximum value of the VSENSE voltage for any given module input voltage. This drop vastly increases the allowable module input voltage and ambient temperature range as discussed in Thermal Considerations.