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Others have pointed out that your values for R102 and R103 are far too large. One of the purposes of R102, besides setting the adjustment pin potential, is to draw current from the LM317's output, even under no load conditions.

The datasheet says on page 6, that "minimum load current to maintain regulation" is typically 3.5mA, or at worst, 10mA. Example schematics in the datasheet all use a value of 240Ω, for R102, resulting in 5mA through it, even with no other load.

Even if you fixed that, I think your expectation of achieving an output voltage variation of less than 30mV, under various load conditions and input voltages, is optimistic. If 30mV change is a problem, then you should really consider using a precision reference. The go-to jellybean device is the TL431, and it absolutely rocks.

It's a shunt regulator, like a zener diode, and you use it in the same way, but it uses two external resistors (R1 and R2 below) to obtain whatever voltage you desire.

It seems, from your schematic, that you need references of 12.7V, 11.3V, 8.8V and 7.7V. All these can be derived like this:

^{simulate this circuit – Schematic created using CircuitLab}

12.7V is a bit too close to the 13V output of the LM317. If you power this circuit from +13V, R3 would have to be very small to pass sufficient current for the TL431, and all the dividers. Then, even small deviations from 13V would result in large changes to current through the TL431, that would diminish the otherwise excellent regulation of this device.

As shown, you can expect way better than 1% regulation, perhaps even approaching 0.1% of variation in the 24V supply.

Others have pointed out that your values for R102 and R103 are far too large. One of the purposes of R102, besides setting the adjustment pin potential, is to draw current from the LM317's output, even under no load conditions.

The datasheet says on page 6, that "minimum load current to maintain regulation" is typically 3.5mA, or at worst, 10mA. Example schematics in the datasheet all use a value of 240Ω, for R102, resulting in 5mA through it, even with no other load.

Even if you fixed that, I think your expectation of achieving an output voltage variation of less than 30mV, under various load conditions and input voltages, is optimistic. If 30mV change is a problem, then you should really consider using a precision reference. The go-to jellybean device is the TL431, and it absolutely rocks.

It's a shunt regulator, like a zener diode, and you use it in the same way, but it uses two external resistors (R1 and R2 below) to obtain whatever voltage you desire.

It seems, from your schematic, that you need references of 12.7V, 11.3V, 8.8V and 7.7V. All these can be derived like this:

^{simulate this circuit – Schematic created using CircuitLab}

12.7V is a bit too close to the 13V output of the LM317. If you power this circuit from +13V, R3 would have to be very small to pass sufficient current for the TL431, and all the dividers. Then, even small deviations from 13V would result in large changes to current through the TL431, that would diminish the otherwise excellent regulation of this device.

As shown, you can expect way better than 1% regulation, perhaps even approaching 0.1% of variation in the 24V supply.

Others have pointed out that your values for R102 and R103 are far too large. One of the purposes of R102, besides setting the adjustment pin potential, is too draw current from the LM317's output, even under no load conditions.

The datasheet says on page 6, that "minimum load current to maintain regulation" is typically 3.5mA, or at worst, 10mA. Example schematics in the datasheet all use a value of 240Ω, for R102, resulting in 5mA through it, even with no other load.

Even if you fixed that, I think your expectation of achieving an output voltage variation of less than 30mV, under various load conditions and input voltages, is optimistic. If 30mV change is a problem, then you really consider using a precision reference. The go-to jellybean device is the TL431, and it absolutely rocks.

It's a shunt regulator, like a zener diode, and you use it in the same way, but it uses two external resistors (R1 and R2 below) to obtain whatever voltage you desire.

It seems, from your schematic, that you need references of 12.7V, 11.3V, 8.8V and 7.7V. All these can be derived like this:

^{simulate this circuit – Schematic created using CircuitLab}

12.7V is a bit too close to the 13V output of the LM317. If you power this circuit from +13V, R3 would have to be very small to pass sufficient current for the TL431, and all the dividers. Then, even small deviations from 13V would result in large changes to current through the TL431, that would diminish the otherwise excellent regulation of this device.

As shown, you can expect way better than 1% regulation, perhaps even approaching 0.1% of variation in the 24V supply.

Others have pointed out that your values for R102 and R103 are far too large. One of the purposes of R102, besides setting the adjustment pin potential, is to draw current from the LM317's output, even under no load conditions.

The datasheet says on page 6, that "minimum load current to maintain regulation" is typically 3.5mA, or at worst, 10mA. Example schematics in the datasheet all use a value of 240Ω, for R102, resulting in 5mA through it, even with no other load.

Even if you fixed that, I think your expectation of achieving an output voltage variation of less than 30mV, under various load conditions and input voltages, is optimistic. If 30mV change is a problem, then you should really consider using a precision reference. The go-to jellybean device is the TL431, and it absolutely rocks.

It's a shunt regulator, like a zener diode, and you use it in the same way, but it uses two external resistors (R1 and R2 below) to obtain whatever voltage you desire.

It seems, from your schematic, that you need references of 12.7V, 11.3V, 8.8V and 7.7V. All these can be derived like this:

^{simulate this circuit – Schematic created using CircuitLab}

12.7V is a bit too close to the 13V output of the LM317. If you power this circuit from +13V, R3 would have to be very small to pass sufficient current for the TL431, and all the dividers. Then, even small deviations from 13V would result in large changes to current through the TL431, that would diminish the otherwise excellent regulation of this device.

As shown, you can expect way better than 1% regulation, perhaps even approaching 0.1% of variation in the 24V supply.

Others have pointed out that your values for R102 and R103 are far too large. One of the purposes of R102, besides setting the adjustment pin potential, is too draw current from the LM317's output, even under no load conditions.

The datasheet says on page 6, that "minimum load current to maintain regulation" is typically 3.5mA, or at worst, 10mA. Example schematics in the datasheet all use a value of 240Ω, for R102, resulting in 5mA through it, even with no other load.

Even if you fixed that, I think your expectation of achieving an output voltage variation of less than 30mV, under various load conditions and input voltages, is optimistic. If 30mV change is a problem, then you really consider using a precision reference. The go-to jellybean device is the TL431, and it absolutely rocks.

It's a shunt regulator, like a zener diode, and you use it in the same way, but it uses two external resistors (R1 and R2 below) to obtain whatever voltage you desire.

It seems, from your schematic, that you need references of 12.7V, 11.3V, 8.8V and 7.7V. All these can be derived like this:

^{simulate this circuit – Schematic created using CircuitLab}

12.7V is a bit too close to the 13V output of the LM317. If you power this circuit from +13V, R3 would have to be very small to pass sufficient current for the TL431, and all the dividers. Then, even small deviations from 13V would result in large changes to current through the TL431, that would diminish the otherwise excellent regulation of this device.

As shown, you can expect way better than 1% regulation.

Others have pointed out that your values for R102 and R103 are far too large. One of the purposes of R102, besides setting the adjustment pin potential, is too draw current from the LM317's output, even under no load conditions.

The datasheet says on page 6, that "minimum load current to maintain regulation" is typically 3.5mA, or at worst, 10mA. Example schematics in the datasheet all use a value of 240Ω, for R102, resulting in 5mA through it, even with no other load.

Even if you fixed that, I think your expectation of achieving an output voltage variation of less than 30mV, under various load conditions and input voltages, is optimistic. If 30mV change is a problem, then you really consider using a precision reference. The go-to jellybean device is the TL431, and it absolutely rocks.

It's a shunt regulator, like a zener diode, and you use it in the same way, but it uses two external resistors (R1 and R2 below) to obtain whatever voltage you desire.

It seems, from your schematic, that you need references of 12.7V, 11.3V, 8.8V and 7.7V. All these can be derived like this:

^{simulate this circuit – Schematic created using CircuitLab}

12.7V is a bit too close to the 13V output of the LM317. If you power this circuit from +13V, R3 would have to be very small to pass sufficient current for the TL431, and all the dividers. Then, even small deviations from 13V would result in large changes to current through the TL431, that would diminish the otherwise excellent regulation of this device.

As shown, you can expect way better than 1% regulation, perhaps even approaching 0.1% of variation in the 24V supply.