Datasheet

MAX5088/MAX5089
2.2MHz, 2A Buck Converters with an
Integrated High-Side Switch
_______________________________________________________________________________________ 3
ELECTRICAL CHARACTERISTICS (continued)
(V+ = V
L
= 5V or V+ = 5.5V to 23V, V
EN
= 5V, T
A
= T
J
= -40°C to +125°C, unless otherwise noted. Circuits of Figures 5 and 6. Typical
values are at T
A
= T
J
= +25°C.) (Note 1)
PARAMETER SYMBOL CONDITIONS
MIN
TYP
MAX
UNITS
SOFT-START
Digital Soft-Start Period Internal 6-bit DAC
4096
Clock
periods
Soft-Start Steps 64
Steps
ERROR AMPLIFIER (FB and COMP)
FB to COMP Transconductance g
M
1.20
1.8
2.75
mS
FB Input Bias Current I
FB
250 nA
FB Input Voltage Set Point V
FB
0.5940 0.601 0.6095
V
COMP Sink-and-Source Current
Capability
I
COMP
100 150
µA
INTERNAL MOSFETs
On-Resistance n-Channel Power
MOSFET
R
ON
V+ = V
L
= 5.2V, I
SINK
= 100mA
0.150 0.302
Ω
Leakage Current I
LEAK
V
EN
= 0V, V
DRAIN
= 23V,
SOURCE = PGND
20 µA
Minimum Output Current I
OUT
V
OUT
= 3.3V, V+ = 12V (Note 2) 2 A
Current Limit I
LIMIT
2.2 2.8 3.5 A
On-Resistance Internal Low-Side
Switch
R
ONLSW
I
SWITCH
= 50mA, V+ = V
L
= 5.2V 20 38 Ω
SYNCHRONOUS RECTIFIER DRIVER (DL) (MAX5089 Only)
On-Resistance nMOS R
ONDLN
I
SINK
= 0.1A 1 6.7 Ω
On-Resistance pMOS R
ONDLP
I
SOURCE
= 0.1A 1.9
11.1
Ω
Peak Sink Current I
IDL_SINK
1A
Peak Source Current
I
IDL_SOURCE
0.75
A
OSCILLATOR (OSC)/SYNCHRONIZATION (SYNC)/CLOCK OUTPUT (CKO) (MAX5088 Only)
Clock Output-High Level V
CKOH
V
L
= 5.2V, I
SOURCE
= 5mA
3.54
V
Clock Output-Low Level V
CKOL
V
L
= 5.2V, I
SINK
= 5mA 0.4 V
R
OSC
= 5.62kΩ
1900 2100 2400
R
OSC
= 41.2kΩ
275 312
350
Switching Frequency f
SW
V+ = V
L
= 5.2V
R
OSC
= 10kΩ
1130 1250 1380
kHz
Minimum Controllable On-Time t
ON_MIN
120
ns
MAX5088 82
87.5
Maximum Duty Cycle D
MAX
f
SW
= 2.2MHz
MAX5089 82
87.5
%