SLCS146G February 2005 – July 2024
PRODUCTION DATA
In a typical shunt regulator configuration (see Figure 7-4), an external resistor, RS, is connected between the supply and the cathode of the LM4041. RS must be set properly, this sets the total current available to supply the load (IL) and bias the LM4041 (IZ). In all cases, IZ must stay within a specified range for proper operation of the reference. Taking into consideration one extreme in the variation of the load and supply voltage (maximum IL and minimum VS), RS must be small enough to supply the minimum IZ required for operation of the regulator, as given by data sheet parameters. At the other extreme, maximum VS and minimum IL, RS must be large enough to limit IZ to less than the maximum recommended rating of 12mA.
RS is calculated as shown in Equation 1.