Linear regulators are simple and low-ripple — ideal for powering analog blocks, sensors and MCUs. The cost is that the entire dropout turns into heat, so selection is a triangle of current, dropout and dissipation.
Reading the Key Parameters
- Input voltage: up to 42V in the catalog (TS6122 series); the other series top out at 6V–25V, covering 5V/12V rails and battery-powered step-down needs.
- Output current: 100mA / 150mA / 250mA / 1000mA tiers — size by peak load current, not average.
- Quiescent current Iq: down to 2μA (TS6122 series), about 25μA for TS6123 and 36μA for TS6112, while TS1117/TS7805-class regulators sit in the mA range — the figure that matters on always-on battery paths.
- PSRR: 50–80dB across the listed parts; the 70dB-plus tier suits second-stage cleanup for noise-sensitive loads like ADCs and clocks.
- Series positioning: general-purpose (TS1117, adjustable and fixed), fixed standard-5V (TS7805/TS78L05), low-power (TS6112), micro-power high-input-voltage (TS6122) and 1A low-voltage (TS6123) families — split first by output form (fixed vs adjustable) and input-voltage class.
Three Steps
- Pick the 100mA / 150mA / 250mA / 1000mA tier by peak load current;
- Estimate dissipation as (Vin−Vout)×Iload and confirm the package can shed it;
- Check Iq for battery standby paths and PSRR for noise-sensitive loads.
Common Pitfalls
- Sizing by average current and sagging out of regulation on transients;
- Forcing large dropout at high current — that's using the LDO as a resistor-heater; buck first, then LDO-clean;
- Ignoring output-capacitor ESR requirements and oscillating.
Filter in the online parametric tool; for fit questions, submit a part-number inquiry.