Texas Instruments Evaluation Board for the LM10506 LM10506EVAL/NOPB LM10506EVAL/NOPB 数据表
产品代码
LM10506EVAL/NOPB
Ideal Inductor,
no resistance
Load
Resistance
Load
Capacitance
Capacitance
VIN_B2
High Side FET
Model of Inductor
Equivalent Circuit of Bypass Operation of Buck 2
(Not Applicable to LM10506-B)
SW_B2
V
OUT
Buck2
Ideal Inductor,
no resistance
DCR
100 m
Max.
Load
Resistance
Load
Capacitance
Capacitance
VIN_B1
High Side FET
Model of Inductor
Equivalent Circuit of Bypass Operation of Buck 1
SW_B1
V
OUT
Buck1
Bypass FET
FB_B1
DCR
100 m
Max.
SNVS729E – SEPTEMBER 2011 – REVISED MARCH 2013
Low Dropout Operation
The device can operate at 100% duty cycle (no switching; PMOS switch completely on) for low dropout support.
In this way the output voltage will be controlled down to the lowest possible input voltage. When the device
operates near 100% duty cycle, output voltage ripple is approximately 25 mV.
In this way the output voltage will be controlled down to the lowest possible input voltage. When the device
operates near 100% duty cycle, output voltage ripple is approximately 25 mV.
The minimum input voltage needed to support the output voltage:
V
IN_MIN
=V
OUT
+I
LOAD
*(R
DSON_PFET
+R
IND
), where
•
I
LOAD
= Load Current
•
R
DSON_PFET
= Drain to source resistance of PFET (high side) switch in the triode region
•
R
IND
= Inductor resistance
Out of Regulation
When any of the Buck outputs are taken out of regulation (below 85% of the output level) the device will start a
shutdown sequence and all other outputs will switch off normally. The device will restart when the forced out-of-
regulation condition is removed.
shutdown sequence and all other outputs will switch off normally. The device will restart when the forced out-of-
regulation condition is removed.
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