From ba03086eeb3777a34577f4e4856b2d81c464c1f4 Mon Sep 17 00:00:00 2001 From: Denis Chevalier Date: Mon, 10 Aug 2026 23:27:44 +0200 Subject: cleaning up and properly typesetting emdashes --- module-design.typ | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) (limited to 'module-design.typ') diff --git a/module-design.typ b/module-design.typ index 54fba92..171f707 100644 --- a/module-design.typ +++ b/module-design.typ @@ -815,8 +815,8 @@ Precision of $qty(10, "ppm")$ means the maximum acceptable error is: $ epsilon_"max" = qty(20, "V") times num("10e-6") = qty(200, "uV") $ -This is our total error budget. Every error source - noise, drift, offset, -nonlinearity - must sum to less than $qty(200, "uV")$ referred to output +This is our total error budget. Every error source (noise, drift, offset, +nonlinearity) must sum to less than $qty(200, "uV")$ referred to output ($upright("RTO")$), or equivalently, $qty(10, "ppm")$ referred to full scale ($upright("FS")$) @@ -843,9 +843,9 @@ $ This appears to conflict with our $qty(200, "uV")$ precision requirement. The resolution is that _precision_ and _noise_ are different specifications: -/ Precision: Applies to the _mean_ of the signal - systematic errors, offset, - gain error, linearity. -/ Noise: Applies to the _variance_ - random fluctuations around the mean. +/ Precision: Applies to the _mean_ of the signal (systematic errors, offset, + gain error, linearity). +/ Noise: Applies to the _variance_: random fluctuations around the mean. A measurement averaged over sufficient time can achieve precision better than the instantaneous noise floor. However, for real-time computation (DC to @@ -2047,6 +2047,13 @@ dynamic and independent. Mitigation requires strict structural and layout rule: - Requiring star grounding for power return lines to keep $Z_"shared" arrow 0$ per @grounding-rules. +==== Drift sources + +Drift sources contribute to the systematic error budget over time. Unlike noise, +drift is deterministic: it has identifiable physical causes and can be +compensated through appropriate topologies. Drift determines the useful +computation duration before recalibration is required. + == Error compensation strategies == Advanced compensation topologies -- cgit