Electronic Components Datasheet Search
  English  ▼

Delete All
ON OFF
ALLDATASHEET.COM

X  

Preview PDF HTML

MAX15010ATJ+ Datasheet(PDF) 19 Page - Maxim Integrated Products

Part No. MAX15010ATJ+
Description  Automotive 300mA LDO Voltage Regulators with Tracker Output and Overvoltage Protector
Download  23 Pages
Scroll/Zoom Zoom In 100% Zoom Out
Maker  MAXIM [Maxim Integrated Products]
Homepage  http://www.maxim-ic.com
Logo 

MAX15010ATJ+ Datasheet(HTML) 19 Page - Maxim Integrated Products

 
Zoom Inzoom in Zoom Outzoom out
 19 / 23 page
background image
Calculate the discharge time, t1, using the following
equation:
where t1 is in ms, VOV is the adjusted overvoltage
threshold in volts, ILOAD is the external load current in
mA, and IGATEPD is the 63mA (typ) internal pulldown
current of GATE. CSOURCE is the value of the capacitor
connected between the source of the MOSFET and
PGND in µF.
GATE Delay Time (t2)
When SOURCE falls 4% below the overvoltage threshold
voltage, the internal current sink is disabled and the
internal charge pump begins recharging the external
GATE voltage. Due to the external load, the SOURCE
voltage continues to drop until the gate of the MOSFET is
recharged. The time needed to recharge GATE and re-
enhance the external MOSFET is approximately:
where t2 is in µs, Ciss is the input capacitance of the
MOSFET in pF, and VGS(TH) is the gate-to-source thresh-
old voltage of the MOSFET in volts. VF is the 0.7V (typ)
internal clamp diode forward voltage of the MOSFET in
volts, and IGATE is the charge-pump current 45µA (typ).
Any external capacitance between GATE and PGND will
add up to Ciss.
During t2, the SOURCE capacitance, CSOURCE, loses
charge through the output load. The voltage across
CSOURCE, ΔV2, decreases by ΔV2 until the MOSFET
reaches its VGS(TH) threshold. Approximate ΔV2 using
the following formula:
SOURCE Output Charge Time (t3)
Once the GATE voltage exceeds the gate-to-source thresh-
old, VGS(TH), of the external MOSFET, the MOSFET turns
on and the charge through the internal charge pump with
respect to the drain potential, QG, determines the slope of
the output-voltage rise. The time required for the SOURCE
voltage to rise again to the overvoltage threshold is:
where ΔVSOURCE = (VOV x 0.04) + ΔV2 in volts, and
Crss is the MOSFET’s reverse transfer capacitance in
pF. Any external capacitance between GATE and
PGND adds up to Crss.
Power Dissipation/Junction Temperature
During normal operation, the MAX15008/MAX15010
has two main sources of internal power dissipation: the
LDO and the voltage tracker.
Calculate the power dissipation due to the LDO as:
PLDO = (VIN - VOUT_LDO) x IOUT_LDO
where VIN is the LDO input supply voltage in volts,
VOUT_LDO is the output voltage of the LDO in volts, and
IOUT_LDO is the LDO total load current in mA.
Calculate power dissipation due to the tracker as:
PTRK = (VTRACK - VOUT_TRK) x IOUT_TRK
where VTRACK is the tracker input supply voltage in
volts, VOUT_TRK is the output voltage of the tracker in
volts, and IOUT_TRK is the tracker load current in mA.
The total power dissipation PDISS in mW as:
PDISS = PLDO + PTRK
For prolonged exposure to overvoltage events, use the
VIN and VTRACK voltages expected during overvoltage
conditions. Under these circumstances the corre-
sponding internal power dissipation contribution, POVP,
calculated in the
Overvoltage-Limiter Mode Switching
Frequency section should also be included in the total
power dissipation, PDISS.
For a given ambient temperature, TA, calculate the
junction temperature, TJ, as follows:
TJ = TA + PDISS x
θJA
where TJ and TA are in °C and
θJA is the junction-to-
ambient thermal resistance in °C/W as listed in the
Absolute Maximum Ratings section.
The junction temperature should never exceed +150°C
during normal operation.
Thermal Protection
When the junction temperature exceeds TJ = +160°C,
the MAX15008/MAX15010 shut down to allow the
device to cool. When the junction temperature drops to
+140°C, the thermal sensor turns all enabled blocks
on again, resulting in a cycled output during continu-
ous thermal-overload conditions. Thermal protection
protects the MAX15008/MAX15010 from excessive
power dissipation. For continuous operation, do not
exceed the absolute maximum junction temperature
rating of +150°C.
t
CV
I
rss
SOURCE
GATE
3 =
×Δ
ΔV
It
C
LOAD
SOURCE
2
2
=
×
tC
VV
I
iss
GS TH
F
GATE
2
+
()
tC
0.04
V
II
1
SOURCE
OV
LOAD
GATEPD
×
+
Automotive 300mA LDO Voltage Regulators
with Tracker Output and Overvoltage Protector
______________________________________________________________________________________
19


Html Pages

1  2  3  4  5  6  7  8  9  10  11  12  13  14  15  16  17  18  19  20  21  22  23 


Datasheet Download




Link URL




Privacy Policy
ALLDATASHEET.COM
Does ALLDATASHEET help your business so far?  [ DONATE ]  

About Alldatasheet   |   Advertisement   |   Datasheet Upload   |   Contact us   |   Privacy Policy   |   Alldatasheet API   |   Link Exchange   |   Manufacturer List
All Rights Reserved© Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn