A novel mini-light-emitting diode (mini-LED) driving circuit based on the low-temperature polysilicon thin-film transistors (LTPS TFTs) for used in the active matrix (AM) backlight unit (BLU) of a liquid-crystal display (LCD) is proposed. By the pulsewidth modulation driving method, the mini-LED is operated at a high luminance efficacy point than that is achieved using the pulse-amplitude modulation (PAM) method to reduce the power consumption at a low gray level. To generate the uniform driving current of the mini-LED, the threshold voltage (

${V}_{\text {TH}}$

) variation of the driving thin-film transistor (TFT) is compensated for by the diode-connection structure. Since the large driving current could exacerbate the current–resistance effect in the power source line, the negative supply voltage (VSS)

${I}$

–

${R}$

rise is also compensated for. The

${V}_{\text {TH}}$

variation of the control TFT is compensated for by the matched TFT method to ensure the precise emission time of the mini-LED. The results of a simulation based on the fitting model of the LTPS TFTs indicate that the relative time shifts are below

$0.581~\mu \text{s}$

. The samples of the proposed circuit are fabricated to verify the feasibility of compensation in the proposed mini-LED BLU. Measurements demonstrate that the maximum error rate among samples is 1.46%. When the VSS rises from −6 to −5 V, the measured current error rates are all less than 6.03%. Hence, the proposed circuit is verified to generate uniform driving currents for the mini-LED BLU of LCDs.

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