Datasheet

MAX8597/MAX8598/MAX8599
Low-Dropout, Wide-Input-Voltage,
Step-Down Controllers
_______________________________________________________________________________________ 5
ELECTRICAL CHARACTERISTICS (continued)
(V
V+
= V
VL
= V
AVL
= V
EN
= V
REFIN
= 5V, V
BST
= 6V, V
LX
= 1V, C
VL
= 4.7µF, C
REFOUT
= 1µF, V
AIN-
= V
AOUT
, V
AIN+
= 2.5V, V
ILIM
=
V
LX
- 0.2V, V
FB
= 0.65V, GND = PGND = 0V, C
SS
= 0.01µF, R
FREQ
= 20kΩ, T
A
= -40°C to +85°C, typical values are at T
A
= +25°C,
unless otherwise noted.) (Note 1)
PARAMETER CONDITIONS MIN TYP MAX UNITS
FREQUENCY
R
FREQ
= 100kΩ 140 240
R
FREQ
= 20.0kΩ 800 1200Frequency
R
FREQ
= 14.3kΩ 1100 1700
kHz
DH Minimum Off-Time 180 230 ns
DH Minimum On-Time 140 ns
FB ERROR AMPLIFIER
FB Input Bias Current 150 nA
FB Input Voltage Set Point Over load and line 0.591 0.606 V
FB Offset Error V
REFIN
= 1.25V and 2.5V, measured with respect to REFIN +20 -20 mV
Error-Amp Open-Loop Voltage
Gain
V
COMP
= 1.2V to 2.4V 72 dB
UNCOMMITTED OPERATIONAL AMPLIFIER (MAX8597 only)
Output Voltage Swing High V
AIN+
= 2.5V, V
AIN
- = (V
AIN+
- 100mV), I
SOURCE
= 100µA
V
AVL
-
20mV
V
Output Voltage Swing Low V
AIN+
= 2.5V, V
AIN
- = (V
AIN+
+ 100mV), I
SINK
= 100µA 20 mV
Input Offset Voltage V
CM
= 1.25V and 2.5V -3 +3 mV
Input Common-Mode Range
(CMVR)
+0.50
V
AVL
-
2.0
V
DRIVERS
DH On-Resistance in Low State V
BST
- V
LX
= 5V 2.5 Ω
DH On-Resistance in High State V
BST
- V
LX
= 5V 3.3 Ω
DL On-Resistance in Low State V
VL
= V
V+
= 5V 1.0 Ω
DL On-Resistance in High State V
VL
= V
V+
= 5V 3.5 Ω
BST Bias Current V
BST
= 33V, V
LX
= 28V, V
EN
= 0V 520 µA
LX Bias Current V
BST
= 33V, V
LX
= 28V, V
EN
= 0V -520 µA
BST/LX Leakage Current V
BST
= V
LX
= 28V, V
EN
= 0V 50 µA
LOGIC INPUTS (EN)
Input Low Level 4.5V < V
VL
= V
V+
= V
AVL
< 5.5V 0.8 V
Input High Level 4.5V < V
VL
= V
V+
= V
AVL
< 5.5V 2.4 V
Input Bias Current V
VL
= V
V+
= V
AVL
= 5.5V, V
EN
= 0 to 5.5V -1 +1 µA
REFIN INPUT (MAX8597 only)
REFIN Input Voltage Range 0 2.75 V
REFIN Dual-Mode Threshold
V
AVL
-
1.0
V
AVL
-
0.5
V
REFIN Input Bias Current V
REFIN
= 1.25V or 2.5V -250 +250 nA