Datasheet BL8536 (Belling) - 4

BL8536 Iq vs. Temperature Ou tput Voltage vs. Temperature
30 Supply current at Vin 3.5 25 Quiescent Current at Vout 3.4 20
)
15 3.3
) uA (V Iq(
10
out
3.2
V
5 3.1 Vin=1.0V 0 Vin=2.6V -5 3.0 -50 0 50 100 -40 0 40 80 120
Temperature(
℃
) Temperature(
℃
) BLOCK DIAGRAM DETAILED DESCRIPTION
control loop. The GM stage integrates the error between FB and REF, and its output is used to BL8536 is a low input voltage start up, current compare with a triangular wave which the summing mode DC-DC step up converter. It’s operation can result of the current sense amplifier output and a be best understood by referring to the block slope compensation voltage. The output of the diagram. Upon starting up, the low voltage startup comparator is used to drive the power stage to circuitry drives SW with on-off cycles, transferring reach regulation. energy from input to OUT by storing energy in the inductor during on-time and releasing it to the
APPLICATION INFORMATION
output during off-time. When OUT reaches 2V, the startup circuit turns off and the main controller
Inductor selection
takes over. The main control loop consists of a With switching frequency up to 1MHz, small surface reference, a GM error amplifier, a PWM controller, mount inductors can be used with values from a current sense amplifier, an oscillator, a PWM logic 2.2uH to 4.7uH. For a given chosen inductor value control, and it is power stage including its driver. and application conditions make sure the peak The main control loop is a classic current mode www.belling.com.cn
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