
Seiko Instruments Inc
The S-1172 Series, developed based on CMOS technology, is a positive voltage regulator with a super low dropout voltage, high output voltage accuracy, and low current consumption. The S-1172 Series provides the very small dropout voltage and the large output current due to the built-in transistor with low on-resistance. The overcurrent protector prevents the load current from exceeding the capacitance of output transistor. The thermal shutdown circuit prevents damage caused by heat, the rush current control circuit limits the excessive rush current during start-up.
Features
• Output voltage : 1.0 to 5.0 V, selectable in 0.05 V step.
• Low equivalent series resistance capacitor : Ceramic capacitor of 4.7 µF or more can be used as the I/O capacitor.
• Input voltage : 1.5 to 5.5 V
• High-accuracy output voltage : ±1.0% (1.0 to 1.45 V output product : ±15 mV)
• Low dropout voltage : 70 mV typ. (3.0 V output product, at IOUT = 300 mA)
• Low current consumption : During operation : 70 µA typ., 90 µA max.
(3.0 V output product)
During shutdown : 0.1 µA typ., 1.0 µA max.
• Output current : 1000 mA (3.0 V output product, at VIN ≥ VOUT(S) + 1.0 V)*1
• High ripple rejection : 70 dB typ. (at 1.0 kHz, VOUT = 1.0 V)
• Built-in overcurrent protection circuit : limits overcurrent of output transistor
• Built-in thermal shutdown circuit : prevents damage caused by heat
• Built-in rush current control circuit : limits excessive rush current during start-up
• Built-in power on/off circuit : Longer battery life
• Small package : SOT-89-5, HSOP-6
• Lead-free product
*1. Attention should be paid to the power dissipation of the package when the output current is large.
Applications
• Power supply for battery-powered devices
• Power supply for TV, notebook PCs and home electric appliances
• Constant-voltage power supply for portable equipment