Datasheet

MAX8795A
TFT-LCD DC-DC Converter with
Operational Amplifiers
_______________________________________________________________________________________ 3
ELECTRICAL CHARACTERISTICS (continued)
(V
IN
= 3V, V
MAIN
= V
SUP
= 14V, V
PGND
= V
AGND
= V
BGND
= 0V, I
REF
= 25µA, T
A
= 0°C to +85°C. Typical values are at T
A
= +25°C,
unless otherwise noted.)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
FB Transconductance ∆I
COMP
= ±2.5µA 75 160 280 µS
FB Voltage Gain From FB to COMP 700 V/ V
LX On-Resistance R
LX
(
ON
)
I
LX
= 200mA 160 260 mΩ
LX Leakage Current I
LX
V
LX
= 19V 10 20 µA
LX Current Limit I
LIM
V
FB
= 1.2V, duty cycle = 75% 2.5 3.0 3.5 A
Current-Sense Transresistance 0.1 0.2 0.3 V/A
Soft-Start Period t
SS
14 ms
Soft-Start Step Size
V
REF
/
128
V
OPERATIONAL AMPLIFIERS
SUP Supply Range V
SUP
6.0 18.0 V
S U P O ver vol tag e Faul t Thr eshol d 18.0 19 19.9 V
SUP Supply Current I
SUP
Buffer configuration, V
POS
_ = V
SUP
/ 2,
no load
3.5 5.0 mA
Input Offset Voltage V
OS
(V
NEG
_, V
POS
_, V
OUT
_) ≅ V
SUP
/ 2 0 12 mV
Input Bias Current I
BIAS
(V
NEG
_ , V
POS
_, V
OUT
_) ≅ V
SUP
/ 2 -50 0 +50 nA
Input Common-Mode Voltage
Range
V
CM
0V
SUP
V
Common-Mode Rejection Ratio CMRR 0 ≤ (V
NEG
_, V
POS
_) ≤ V
SUP
45 80 dB
Open-Loop Gain 125 dB
Output Voltage Swing, High V
OH
I
OUT
_ = 5mA
V
SUP
-
100
V
SUP
-
50
mV
Output Voltage Swing, Low V
OL
I
OUT
_ = -5mA 50 100 mV
Short-Circuit Current To V
SUP
/ 2, source or sink 75 130 mA
Power-Supply Rejection Ratio PSRR
DC, 6V ≤ V
SUP
≤ 18V,
(V
NEG
_, V
POS
_) ≅ V
SUP
/ 2
60 dB
Slew Rate 45 V/µs
-3dB Bandwidth R
L
= 10kΩ, C
L
= 10pF, buffer configuration 20 MHz
GATE-ON LINEAR-REGULATOR CONTROLLER
FBP Regulation Voltage V
FBP
I
DRVN
= 100µA 1.231 1.250 1.269 V
FBP Fault Trip Level V
FBP
falling 0.96 1.00 1.04 V
FBP Input Bias Current I
FBP
V
FBP
= 1.25V -50 +50 nA
FBP Effective Load-Regulation
Error (Transconductance)
V
DRVP
= 10V, I
DRVP
= 50µA to 1mA -0.7 -1.5 %
FBP Line (IN) Regulation Error I
DRVP
= 100µA, 2.5V < V
IN
< 6V ±1 ±10 mV
DRVP Sink Current I
DRVP
V
FBP
= 1.1V, V
DRVP
= 10V 1 5 mA
DRVP Off-Leakage Current V
FBP
= 1.4V, V
DRVP
= 34V 0.01 10 µA
Soft-Start Period t
SS
14 ms
Soft-Start Step Size
V
REF
/
128
V