MAX8745 Maxim Integrated Products, MAX8745 Datasheet - Page 4

• Manufacturer Part Number: MAX8745
• Description: (MAX8744 / MAX8745) Main Power-Supply Controllers
• Manufacturer: Maxim Integrated Products

High-Efficiency, Quad Output, Main Power-
Supply Controllers for Notebook Computers
ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1, V
no load, T
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4
Soft-Start Ramp Time
Soft-Stop Ramp Time
INTERNAL FIXED LINEAR REGULATORS
LDO5 Output Voltage
LDO5 Undervoltage-Lockout Fault
Threshold
LDO5 Bootstrap Switch Threshold
LD O 5 Bootstr ap S w i tch Resi stance
Short-Circuit Current
Short-Circuit Current (Switched
over to CSL_)
AUXILIARY LINEAR REGULATOR
DRVA Voltage Range
DRVA Drive Current
FBA Regulation Threshold
FBA Load Regulation
OUTA Shunt Trip Level
FBA Leakage Current
Secondary Feedback Regulation
Threshold
DL5 Pulse Width
OUTA Leakage Current
REFERENCE (REF)
Reference Voltage
Reference Load-Regulation Error
REF Lockout Voltage
FAULT DETECTION
Output Overvoltage Trip
Threshold (MAX8744 Only)
Outp ut Over vol tag e Faul t
P r op ag ati on D el ay ( M AX 8744 Onl y)
_______________________________________________________________________________________
A
PARAMETER
= 0°C to +85°C, unless otherwise noted. Typical values are at T
IN
= 12V, both SMPS enabled, FSEL = REF, SKIP = GND, ILIM = LDO5, FBA = LDO5, I
V
SYMBOL
REF(UVLO)
t
t
SSTART
V
V
ΔV
I
SSTOP
V
V
OUTA
t
DRVA
LDO5
OVP
FBA
REF
REF
Measured from the rising edge of ON_ to
full scale
Measured from the falling edge of ON_ to
full scale
ON5 = GND, 6V < V
0 < I
Rising edge, hysteresis = 1% ( typ )
Ri si ng ed g e of C S L5, hyster esi s = 1% ( typ )
LD O 5 to C S L5, V
LDO5 = GND, ON5 = GND
LDO5 = GND, V
V
V
V
V
Rising edge
V
V
V
LDO5 in regulation, I
I
Rising edge, hysteresis = 100mV (typ)
With respect to error-comparator
threshold
50mV overdrive
REF
FBA
FBA
DRVA
DRA
FBA
DRVA
DRVA
LDO5
= -5µA to +50µA
= 1.05V, V
= 0.965V, V
= 1.035V
= 5V, I
= 5V, I
- V
= V
OUTA
< 100mA
OUTA
DRVA
DRVA
CONDITIONS
CSL5
DRVA
= 25V
C S L 5
DRVA
= 0.5mA to 5mA
= 1mA (sink)
IN
REF
> 4.7V
= 5V , I
= 5V
< 26V,
= 5V
A
= 0
= +25°C.)
L D O5
= 50m A
1.985
MIN
4.85
4.35
0.98
-0.1
200
-10
0.5
10
25
8
3f
TYP
4.95
4.55
1.00
2.00
1.90
-1.2
225
225
425
26
OSC
11
10
1/
2
4
1
0
REF
= I
2.015
MAX
+0.1
5.10
4.70
26.0
1.02
-2.2
+10
450
450
0.4
LDO5
27
50
14
5
= I
UNITS
OUTA
mA
mA
mA
mA
mV
ms
ms
µA
µA
µs
µs
%
%
Ω
V
V
V
V
V
V
V
V
=