/**
 * IPC-2221 conductor current-carrying capacity.
 *
 * Formula (IPC-2221, formerly MIL-STD-275, the widely-cited empirical curve fit):
 *
 *   I = k · ΔT^0.44 · A^0.725
 *
 * where `I` is current in amps, `ΔT` is the allowed temperature rise in °C, `A` is
 * conductor cross-sectional area in mils², and `k` is 0.048 for external (outer
 * layer) conductors or 0.024 for internal conductors.
 *
 * This is an estimate, not a certified value: the curve does not model adjacent-trace
 * heating, via/plane proximity, forced airflow, or altitude. IPC-2152 supersedes
 * IPC-2221 with more conservative guidance for dense modern boards. Verify against
 * your fabricator's process and cross-check with IPC-2152 for safety-critical or
 * high-reliability current paths.
 *
 * @module
 */
export type ConductorLayer = 'external' | 'internal';
/** Standard copper thickness in mils per oz/ft² of copper weight (1oz ≈ 1.378 mils / 34.8 µm). */
export declare const COPPER_THICKNESS_MILS_PER_OZ = 1.378;
export interface TraceWidthInput {
    /** Required current-carrying capacity, in amps. */
    currentA: number;
    /** Allowed conductor temperature rise above ambient, in °C. */
    temperatureRiseC: number;
    /** Whether the trace is on an external (outer) or internal layer. */
    layer: ConductorLayer;
    /** Copper weight in oz/ft² (e.g. 1, 2, 0.5). */
    copperWeightOz: number;
}
export interface TraceWidthResult {
    requiredAreaMils2: number;
    copperThicknessMils: number;
    traceWidthMils: number;
    traceWidthMm: number;
    k: number;
    source: string;
    caveat: string;
}
/** Compute the minimum trace width for a given current, temperature rise, layer, and copper weight. */
export declare function calculateTraceWidth(input: TraceWidthInput): TraceWidthResult;
export interface MaxCurrentInput {
    /** Trace width in mils. */
    traceWidthMils: number;
    /** Allowed conductor temperature rise above ambient, in °C. */
    temperatureRiseC: number;
    layer: ConductorLayer;
    copperWeightOz: number;
}
export interface MaxCurrentResult {
    maxCurrentA: number;
    source: string;
    caveat: string;
}
/** Reverse lookup: the maximum current a given trace width can carry under the same model. */
export declare function calculateMaxCurrent(input: MaxCurrentInput): MaxCurrentResult;