6.0V, 3.0A, 1.2MHz Synchronous Step-Down DC to DC Converter

The HT74173 is a high efficiency synchronous stepdown converter capable of delivering 3A output current. It can operate over a wide input voltage range from 2.5V to 6.0V and integrates 80mΩ low onresistance main and rectified switches to minimize the conduction losses. Up to 1.2MHz switching frequency in PWM allows to use the small surface mount inductors and capacitors in applications.

The automatically PWM/PFM mode switching is useful to drive up to 3A load current and also decrease its standby current in no load condition. The Hysteretic PFM mode extends the battery life by reducing the quiescent current during the system standby. In the shutdown mode, the device turns off and consumes only 0.1μA input current.

The HT74173 also provides 100% duty cycle operation. When the input supply voltage decreases toward the targeted output voltage, the High-Side MOSFET will always turn on and the output voltage tracks the input voltage, which can extend the battery life.

Features:

• wide input range of VIN from 2.5V to 6.0V
• output voltage range from 0.6V to VDD
• internal low on-resistance switches:
  • high-side RDS(ON) 80mΩ
  • low-side RDS(ON) 80mΩ
• 100% duty cycle operation
• switching frequency: 1.2MHz
• PFM mode operation when no load/light load conditions
• output voltage power good indicator when VOUT =0.93×VOUT(TARGET) (8SOP-EP)
• protection features:
  • VDD under voltage lock-out
  • cycle-by-cycle over current protection
  • thermal shutdown protection
  • output short-circuit protection
  • output over-voltage protection
• package types: 8-pin SOP-EP, 5-pin SOT23 and 5-pin SOT89

Specification:

• input voltage: 6V
• output voltage: 0.6V~6V
• output current: 3.0A
• switching frequency: 1200kHz
• current limit: 5.0A
• accuracy: 0.6V±1.5%
• shutdown current: 0.5μA
• operationn current: 50μA
• efficiency: 85%
• mode: PWM/PFM
• case: SOT89-5