max5074aup Maxim Integrated Products, Inc., max5074aup Datasheet - Page 8

• Manufacturer Part Number: max5074aup
• Description: Power Ic With Integrated Mosfets For Isolated Ieee 802.3af Pd And Telecom Power-supply Applications
• Manufacturer: Maxim Integrated Products, Inc.

The MAX5074 PWM power IC is the primary-side
controller for voltage-mode, isolated forward or flyback
power converters. This device provides a high degree of
integration aimed at reducing the cost and printed circuit
board area of isolated output power supplies. Use the
MAX5074 primarily in 48V power bus applications.
Power IC with Integrated MOSFETs for Isolated IEEE
802.3af PD and Telecom Power-Supply Applications
Figure 1. Block Diagram
8
1
4
3
5
6
7
9
FLTINT
RAMP
REGOUT
RCFF
OPTO
CSS
GND
_______________________________________________________________________________________
80µA
33µA
2.7V/1.9V
MAX5074
5V
5V
IFLT
50Ω
REGOK
CPWM
OVRLD
GND
Detailed Description
Q
REG
5V
D
R
T
7.5V
OVT
UVLO
REFOK
REGOK
OVRLD
OVT
CLK
GND
REFOK
50Ω
Q
T-FF
R
T
(1.25V)
R
S
REF
Q
ILIM
SHDN
OSC
UVLO
150mV
The MAX5074 is a complete power IC capable of deliver-
ing up to 15W of output power. This device contains PWM
circuitry and integrated power MOSFETs. Figure 1 shows
the MAX5074’s block diagram. The MAX5074 includes
undervoltage lockout, overtemperature shutdown, and
short-circuit protection for enhanced performance and
reliability. Operation up to 500kHz allows the use of small
external magnetics and capacitors.
SHUTDOWN
THERMAL
CUVLO
DELAY
80ns
10MHz
OVT
PGND
1.25V
LEADING-
DELAY
LEVEL
SHIFT
EDGE
SHOT
ONE
30Ω
0.4Ω
QB
0.4Ω
QH
QL
XFRMRH
XFRMRL
INBIAS
PPWM
DRVIN
DRNH
PGND
UVLO
RTCT
HVIN
SRC
BST
CS
20
19
18
8
17
16
15
14
13
12
11
2
10