MAX8540EEE+ Maxim Integrated Products, MAX8540EEE+ Datasheet - Page 12

• Manufacturer Part Number: MAX8540EEE+
• Description: IC PWM CTRLR CURR-MODE 16-QSOP
• Manufacturer: Maxim Integrated Products

Specifications of MAX8540EEE+

• Pwm Type: Current Mode
• Number Of Outputs: 1
• Frequency - Max: 1MHz
• Duty Cycle: 82%
• Voltage - Supply: 7.6 V ~ 18 V
• Buck: No
• Boost: No
• Flyback: Yes
• Inverting: No
• Doubler: No
• Divider: Yes
• Cuk: No
• Isolated: Yes
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 16-QSOP
• Frequency-max: 1MHz
• Duty Cycle (max): 80 %
• Mounting Style: SMD/SMT
• Switching Frequency: 200 KHz to 1000 KHz
• Maximum Operating Temperature: + 85 C
• Fall Time: 53 ns
• Minimum Operating Temperature: - 40 C
• Rise Time: 57 ns
• Synchronous Pin: Yes
• Topology: Flyback, Forward
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Pull V
enable the latch-off feature. In this mode, once the
SKTON time has elapsed, the IC is latched off. The cir-
cuit remains off until EN is toggled, or the input power is
toggled.
During startup, the capacitor at soft-start is charged
using a 5µA current source. Once the voltage at soft-
start reaches the threshold voltage (2V typ), the IC
switches normally. Use a low-ESR ceramic capacitor
placed as close as possible to the IC at soft-start. The
value is determined as follows:
where t
is in µF.
Refer to the following application notes for the
MAX8540/MAX8541 application circuits and applica-
tions information: 50W Current-Mode Forward
Converter Design with the MAX8540 and 50W Voltage-
Mode Forward Converter Design with the MAX8541.
Synchronizable, High-Frequency Current- and
Voltage-Mode PWM Controllers for Isolated Supplies
12
______________________________________________________________________________________
SKTOFF
SS
is the desired soft-start period in ms and C
to V
Applications Information
Soft-Start Capacitor Selection
REF
C
through a 10kΩ pullup resistor to
SS
=
530
t
SS
SS
TRANSISTOR COUNT: 2704
PROCESS: BiCMOS
TOP VIEW
Pin Configurations (continued)
FREQ/SYNC
MAXDTY
PRAMP
REF
OV
UV
SS
EN
1
2
6
3
4
5
7
8
MAX8541EEE
QSOP
Chip Information
16
15
14
13
12
11
10
9
V
DRV
GND
SKTON
CS
SKTOFF
ILIM
OPTO
CC