Power Electronics

CMOS Voltage Regulator Has High Ripple-Rejection and Low Dropout High Current Output

Sieko's S-1172 has low dropout voltage and high output current, which can be attributed to the built-in transistor with low on-resistance. Also, it has an over-current protector that prevents the load current from exceeding the capacitance of the output transistor while the thermal shutdown circuit prevents damage caused by heat. The rush current control circuit limits the excessive rush current during start-up. Various capacitors and small ceramic capacitors can be used for this IC more than for conventional regulator ICs that have CMOS technology. Additionally, the ON/OFF circuit ensures longer battery life.

High-density mounting can be achieved using a small SOT-89-5 package and high-heat radiation HSOP-6 package.

Typical Features of the S-1172 Series Include:

  • 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 over-current protection circuit: Limits over-current 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
  • RoHS Compliant
TAGS: Regulators
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