A voltage-divider circuit (1B; 1C; 3B; 6A; 6B; 60), comprising: a network of discrete resistors connected together to define T tiers of resistors, where T≥2, the T tiers comprising first and subsequent tiers, each subsequent tier nested within the preceding tier, the Xth tier comprising either one Xth-tier resistor or at least two Xth-tier resistors connected in series where X=1, and the Xth tier comprising at least two Xth-tier resistors connected in series for each value of X in the range 2≤X≤T, wherein for each value of X in the range 2≤X≤T, the Xth-tier resistors connected in series are formed by implementing an X-1th tier resistor as a subdivision network of discrete resistors which comprises a main resistor (R M) connected in series with an auxiliary resistor (R A), that main resistor (R M) implemented as a base resistor (R B) connected in parallel with a series connection (R S) of the Xth-tier resistors, wherein, for each value of X in the range 1≤X<T: each Xth-tier resistor is connected between a pair of nodes of the voltage-divider circuit at which a relatively high voltage signal and a relatively low voltage signal are provided, respectively; and at least one Xth-tier resistor is implemented as a said subdivision network of discrete resistors, and wherein for at least one said subdivision network: its series connection (R S) of resistors comprises S resistors; the auxiliary resistor (R A) is implemented as M resistors connected together in parallel; the base resistor (R B), the S resistors of its series connection (R S) of resistors and the M resistors which implement its auxiliary resistor (R A) all have the same resistance value; and M≥3 and M=S+1. a network of discrete resistors connected together to define T tiers of resistors, where T≥2, the T tiers comprising first and subsequent tiers, each subsequent tier nested within the preceding tier, the Xth tier comprising either one Xth-tier resistor or at least two Xth-tier resistors connected in series where X=1, and the Xth tier comprising at least two Xth-tier resistors connected in series for each value of X in the range 2≤X≤T, wherein for each value of X in the range 2≤X≤T, the Xth-tier resistors connected in series are formed by implementing an X-1th tier resistor as a subdivision network of discrete resistors which comprises a main resistor (R M) connected in series with an auxiliary resistor (R A), that main resistor (R M) implemented as a base resistor (R B) connected in parallel with a series connection (R S) of the Xth-tier resistors, wherein, for each value of X in the range 1≤X<T: each Xth-tier resistor is connected between a pair of nodes of the voltage-divider circuit at which a relatively high voltage signal and a relatively low voltage signal are provided, respectively; and at least one Xth-tier resistor is implemented as a said subdivision network of discrete resistors, each Xth-tier resistor is connected between a pair of nodes of the voltage-divider circuit at which a relatively high voltage signal and a relatively low voltage signal are provided, respectively; and at least one Xth-tier resistor is implemented as a said subdivision network of discrete resistors, and wherein for at least one said subdivision network: its series connection (R S) of resistors comprises S resistors; the auxiliary resistor (R A) is implemented as M resistors connected together in parallel; the base resistor (R B), the S resistors of its series connection (R S) of resistors and the M resistors which implement its auxiliary resistor (R A) all have the same resistance value; and M≥3 and M=S+1. its series connection (R S) of resistors comprises S resistors; the auxiliary resistor (R A) is implemented as M resistors connected together in parallel; the base resistor (R B), the S resistors of its series connection (R S) of resistors and the M resistors which implement its auxiliary resistor (R A) all have the same resistance value; and M≥3 and M=S+1.