I have checked input-current on the EVM Board(steval-isa109v2, STBB2JAD) with output-current is no load. Please refer below.
- EVM Board Spec.
Input voltage: from 2.3 V to 5.5 V
Output voltage: 3.3 V
Output current: 800 mA
Operating frequency: 3 MHz
- EVM Board Condition
EN: connected to VIN
BP: 0 (not Bypass Mode)
MODE: 0 (Auto Mode)
VSEL: connected to VIN
- Procedure
1) Vin = 4.2V, Vout = 3.3V no load -> input-current = less than 1mA
2) Vin = 4.1V, Vout = 3.3V no load -> input-current = less than 1mA
3) Vin = 4.0V, Vout = 3.3V no load -> input-current = less than 1mA
4) Vin = 3.9V, Vout = 3.3V no load -> input-current = less than 1mA
5) Vin = 3.8V, Vout = 3.3V no load -> input-current = less than 1mA
6) Vin = 3.7V, Vout = 3.3V no load -> input-current = less than 1mA
7) Vin = 3.6V, Vout = 3.3V no load -> input-current = less than 1mA
8) Vin = 3.5V, Vout = 3.3V no load -> input-current = less than 1mA
9) Vin = 3.4V, Vout = 3.3V no load -> input-current = less than 1mA
10) Vin = 3.3V, Vout = 3.3V no load -> input-current = less than 1mA
11) Vin = 3.2V, Vout = 3.3V no load -> input-current = less than 1mA
12) Vin = 3.1V, Vout = 3.3V no load -> input-current = less than 1mA
13) Vin = 3.0V, Vout = 3.3V no load -> input-current = less than 1mA
14) Vin = 2.9V, Vout = 3.3V no load -> input-current = less than 1mA
15) Vin = 2.8V, Vout = 3.3V no load -> input-current = about 500mA
Above #15
I expected that input-current will be less than 1mA.
But, input-current is about 500mA and device temperature is about 60 degree.
The inductor is always driven by the DC/DC controller.
How can i reduce the input-current? Need to do Phase correction? Give me advise.
