lp38501 National Semiconductor Corporation, lp38501 Datasheet
lp38501
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lp38501 Summary of contents
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... General Description National's FlexCap LDO's feature unique compensation that allows the use of any type of output capacitor with no limits on minimum or maximum ESR. The LP38501/3 series of low- dropout linear regulators operates from a +2.7V to +5.5V input supply. These ultra low dropout linear regulators respond very quickly to step changes in load, which makes them suitable for low voltage microprocessor applications ...
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... Connection Diagrams for TO-263 (TS) Package Top View (LP38501TS-ADJ) TO-263 Package Connection Diagrams for TO-263 THIN (TJ) Package Top View (LP38501TJ-ADJ, LP38501ATJ-ADJ) TO-263 THIN Package www.national.com 30028122 Top View (LP38503TS-ADJ) 30028162 Top View (LP38503TJ-ADJ, LP38503ATJ-ADJ) 2 30028121 TO-263 Package 30028163 TO-263 THIN Package ...
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... LP38503ATJ-ADJ Function Enable (LP38501 only). Pull high to enable the output, low to disable the output. This pin has no internal bias and must be either tied to the input voltage, or actively driven. In the LP38503, this pin has no internal connections. It can be left floating or used for trace routing ...
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... Note 6) Ground Pin Current In Normal I GND Operation Mode I Ground Pin Current DISABLED I Peak Output Current OUT(PK) I Short Circuit Current SC Enable Input (LP38501 Only) V Enable Logic High IH(EN) V Enable Logic Low IL(EN) t Turn-off delay d(off) t Turn-on delay d(on) I Enable Pin High Current IH(EN) I Enable Pin Low Current IL(EN) www ...
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Symbol Parameter AC Parameters PSRR Ripple Rejection ρ Output Noise Density n(l/f) e Output Noise Voltage n Thermal Characteristics T Thermal Shutdown SD ΔT Thermal Shutdown Hysteresis T SD Thermal Resistance θ J-A Junction to Ambient Thermal Resistance θ J-C ...
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Typical Performance Characteristics µ µ mA OUT OUT Noise Density I vs Load Current GND V vs Temperature ADJ www.national.com Unless otherwise specified 1.8V OUT 30028110 30028111 ...
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V vs Temperature EN 30028116 Load Regulation vs Temperature 30028118 Turn-on Time 30028156 Turn-on Characteristics Turn-on Time PSRR 7 30028117 30028155 30028120 www.national.com ...
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... Block Diagrams www.national.com LP38501-ADJ Block Diagram LP38503-ADJ Block Diagram 8 30028150 30028151 ...
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... The amount of capacitance can be increased without limit. Increasing the size of C typically will give improved load transient response. SETTING THE OUTPUT VOLTAGE The output voltage of the LP38501/3-ADJ can be set to any value between 0.6V and 5V using two external resistors shown as R1 and R2 in Figure 1 ...
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... In gen- L eral, LDO’s have maximum bandwidth (and lowest phase margin) at full load current. In the case of the LP38501, it can be seen that it has good phase margin even when using ce- ramic capacitors with ESR values of only a few milli Ohms. ...
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FIGURE 6. Rising Edge, 10 µF Ceramic, 75A/µs di/dt It can be seen from the figure that the output voltage starts “correcting” back upwards after less than a micro second, and has fully reversed direction after about 1.2 µs. This ...
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... IC to reduce the OUT amount of EMI conducted into the IC. If the LP38501/3-ADJ output is connected to a load which switches at high speed (such as a clock), the high-frequency current pulses required by the load must be supplied by the capacitors on the IC output ...
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... The output can be pulled above the input as long as the cur- rent in the parasitic diode is limited to 200 mA continuous and 1A peak. The regulator output pin should not be taken below ground potential. If the LP38501/3-ADJ is used in a dual-sup- ply system where the regulator load is returned to a negative supply, the output must be diode-clamped to ground. ...
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FIGURE 12. θ vs Copper Area for TO-263 Package JA www.national.com As shown in the figure, increasing the copper area beyond 1.5 square inch produces very little improvement. 30028152 14 ...
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Physical Dimensions inches (millimeters) unless otherwise noted TO-263 5-Lead, Molded, Surface Mount Package TO-263 THIN 5-Lead, Molded, Surface Mount Package NS Package Number TS5B NS Package Number TJ5A 15 www.national.com ...
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... National Semiconductor and the National Semiconductor logo are registered trademarks of National Semiconductor Corporation. All other brand or product names may be trademarks or registered trademarks of their respective holders. ...