LM3370SD-3021/NOPB National Semiconductor, LM3370SD-3021/NOPB Datasheet - Page 15

• Manufacturer Part Number: LM3370SD-3021/NOPB
• Description: IC CONV DC/DC DUAL STPDN 16-LLP
• Manufacturer: National Semiconductor
• Series: PowerWise®r
• Type: Step-Down (Buck)r

Specifications of LM3370SD-3021/NOPB

• Internal Switch(s): Yes
• Synchronous Rectifier: Yes
• Number Of Outputs: 2
• Voltage - Output: 1.2V, 3.3V
• Current - Output: 600mA
• Frequency - Switching: 2MHz
• Voltage - Input: 2.7 ~ 5.5 V
• Operating Temperature: -30°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 16-LLP
• Power - Output: 1.54W
• For Use With: LM3370SD-3021EV - BOARD EVALUATION LM3370SD-3021
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: LM3370SD-3021TR

FORCED PWM MODE
The LM3370 auto mode can be bypassed by forcing the de-
vice to operate in PWM mode, this can be implemented
through the I
SOFT-START
The LM3370 has a soft start circuit that limits in-rush current
during start up. Soft start is activated only if EN goes from
logic low to logic high after V
LDO - LOW DROP OUT OPERATION
The LM3370 can operate at 100% duty cycle (no switching,
PFET switch completely on) for low drop out support of the
2
C compatible interface, see Table 1.
IN
FIGURE 5. Operation in PFM Mode and Transfer to PWM Mode
reaches 2.7V.
15
output voltage. In this way the output voltage will be controlled
down to the lowest possible input voltage. The minimum input
voltage needed to support the output voltage is V
I
• I
• R
• R
LOAD
LOAD
DSON/PFET
INDUCTOR
*(R
DSON,PFET
load current
drain to source resistance of PFET switch in the
triode region
inductor resistance
+ R
INDUCTOR
) + V
OUT
20167303
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IN,MIN
=