Electrical characteristics (continued) – Rainbow Electronics MAX8728 User Manual
Page 5
MAX8728
Low-Cost, Multiple-Output
Power Supply for LCD Monitors/TVs
_______________________________________________________________________________________
5
ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1, V
IN
= V
INL
= V
SUPP
= 12V, V
OUT1
= +3.3V, V
SRC
= 28V, GND1 = GND2 = GNDP = GND = 0, I
REF
= 0, T
A
= 0°C
to +85°C. Typical values are at T
A
= +25°C, unless otherwise noted.)
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
DEL, EN Discharge Switch
On-Resistance
SHDN = low or fault tripped
20
Ω
FBN Discharge Switch
On-Resistance
EN = low or fault tripped
5
k
Ω
POSITIVE GATE-DRIVER TIMING AND CONTROL SWITCHES
CTL Input Low Voltage
0.6
V
CTL Input High Voltage
2.0
V
CTL Input Leakage Current
-1
+1
µA
CTL-to-GON Rising Propagation
Delay
1k
Ω from DRN to GND, 1.5nF from GON to
GND
100
ns
CTL-to-GON Falling Propagation
Delay
1k
Ω from DRN to GND, 1.5nF from GON to
GND
250
ns
SRC Input Voltage Range
38
V
V
MODE
= V
REF
, V
DEL
= V
CTL
= 3V
1.5
2.0
SRC Input Current
V
MODE
= V
REF
, V
DEL
= 3V, V
CTL
= 0
0.14
0.20
mA
DRN Input Current
V
MODE
= V
REF
, V
DRN
= 8V, V
DEL
= 3V,
V
GON
> V
DRN
, V
CTL
= 0
0
1
µA
SRC Switch On-Resistance
V
MODE
= V
REF
, V
DEL
= V
CTL
= 3V
15
30
Ω
SRC Switch Saturation Current
V
MODE
= V
REF
, V
DEL
= V
CTL
= 3V,
V
SRC
- V
GON
> 5V
260
mA
DRN Switch
On-Resistance
V
MODE
= V
REF
, V
DEL
= 3V, V
CTL
= 0, V
GON
= 28V, V
THR
= 1.4V
25
50
Ω
DRN Switch Saturation Current
V
MODE
= V
REF
, V
DEL
= 3V, V
CTL
= 0, V
GON
= 28V, V
THR
= 1.4V, V
GON
- V
DRN
> 5V
100
mA
MODE Switch On-Resistance
SHDN = GND
1
k
Ω
MODE Current-Source Stop
Voltage Threshold
MODE rising
1.2
1.4
1.6
V
MODE Charge Current
Operating mode 2, V
MODE
= 0.7V
40
50
60
µA
MODE Voltage Threshold
Enabling DRN switch control in mode 2
0.8
1.0
1.2
V
THR to GON Voltage Gain
9.4
10.0
10.6
V/V
FAULT DETECTION
Duration to Trigger Fault
50
ms
Thermal Shutdown Threshold
15°C typical hysteresis
+160
°C
SWITCHING-FREQUENCY SELECTION
FSEL = V
CC
(1MHz)
V
CC
- 0.4
FSEL = REF (0.5MHz)
1.65
2.35
FSEL Input Levels
FSEL = GND (1.5MHz)
0.5
V
FSEL Input Current
Forced to V
CC
10
µA