Features

• Wide Input Voltage Range: 3.2V to 34V
• Micropower Operation: I_Q = 12µA
• 5V at 250mA from 6.5V to 34V Input (LT1934)
• 5V at 60mA from 6.5V to 34V Input (LT1934-1)
• 3.3V at 250mA from 4.5V to 34V Input (LT1934)
• 3.3V at 60mA from 4.5V to 34V Input (LT1934-1)
• Low Shutdown Current: <1µA
• Low V_CESAT Switch: 200mV at 300mA
• Low Profile (1mm) SOT-23 (ThinSOT™) and (2mm × 3mm × 0.8mm) 6-Pin DFN Package

Typical Application

Description

The LT1934 is a micropower step-down DC/DC converter with internal 400mA power switch, packaged in a low profile (1mm) ThinSOT. With its wide input range of 3.2V to 34V, the LT1934 can regulate a wide variety of power sources, from 4-cell alkaline batteries and 5V logic rails to unregulated wall transformers and lead-acid batteries. Quiescent current is just 12µA and a zero current shutdown mode disconnects the load from the input source, simplifying power management in battery-powered systems. Burst Mode operation and the low drop internal power switch result in high efficiency over a broad range of load current.

The LT1934 provides up to 300mA of output current. The LT1934-1 has a lower current limit, allowing optimum choice of external components when the required output current is less than 60mA. Fast current limiting protects the LT1934 and external components against shorted outputs, even at 34V input.