Seiko Instruments Introduces New Ultra-Small LDO Voltage Regulator ICs
Seiko Instruments Inc. (SII) announced the S-1312/1313 series, which the company says is the world’s smallest outer lead package (0.8 x 0.8 x 0.4 mm) LDO voltage regulators, featuring 850mW power dissipation, thermal shutdown capability, high ripple rejection, and ultra-low 0.9µA current consumption. The new regulators have been optimized for use in smart phones, cellular phones, digital cameras, notebook PCs, hearing aids, and other battery operated portable device designs.
Thermal shutdown protection is built-in, automatically protecting the circuit when the junction temperature reaches 150°C and restarts regulation when it drops to 120°C. Overcurrent protection is also a built-in feature.
Current consumption has been reduced to extremely low levels (S-1313: 0.9µA and S-1312: 20µA) extending battery and device operating times, while providing excellent ripple rejection of 75 dB (typical). Output voltage is maintained with high accuracy within ± 1.0%.
Utilizing SII’s HSNT-4(0808) ultra-small package (0.8 x 0.8 x 0.4mm), the regulators occupy only one-third the area of conventional SNT-4 package regulators, while enabling automatic visual solder joint inspection, improving manufacturing yields and reliability. The package incorporates a heat sink capable of 850 mW dissipation (board size 40 x 40 x 0.8mm, 4 layers, copper ratio 50%), providing higher reliability and performance.
The outer lead design also decreases failure rates related to circuit board flexing and mechanical shock. This is particularly important for small consumer devices like smart phones that are subjected to constant use.