MAX5053AEUA+ Maxim Integrated Products, MAX5053AEUA+ Datasheet - Page 10

• Manufacturer Part Number: MAX5053AEUA+
• Description: IC CNTRLR PWM CRNT MD 8-UMAX
• Manufacturer: Maxim Integrated Products

Specifications of MAX5053AEUA+

• Pwm Type: Current Mode
• Number Of Outputs: 1
• Frequency - Max: 290kHz
• Duty Cycle: 50%
• Voltage - Supply: 10.8 V ~ 24 V
• Buck: No
• Boost: Yes
• Flyback: No
• Inverting: No
• Doubler: No
• Divider: No
• Cuk: No
• Isolated: Yes
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 8-MSOP, Micro8™, 8-uMAX, 8-uSOP,
• Frequency-max: 290kHz
• Duty Cycle (max): 50 %
• Output Current: 1000 mA
• Mounting Style: SMD/SMT
• Switching Frequency: 262 KHz
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Synchronous Pin: No
• Topology: Boost, Flyback
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

The MAX5052/MAX5053 include an internal error ampli-
fier that can be used to regulate the output voltage in
the case of a nonisolated power supply (see Figure 1)
Calculate the output voltage using the following equation:
Current-Mode PWM Controllers with an Error
Amplifier for Isolated/Nonisolated Power Supplies
Figure 5. Primary Regulated, Dual-Output, Isolated Telecom Power Supply
Figure 6. Internal Oscillator
10
OSCILLATOR
1.048MHz
FB_P
______________________________________________________________________________________
+VIN
SHDN
-VIN
22.6kΩ
2.49kΩ
33kΩ
1%
1%
R1
R2
+V
R6
+V
D
IN
IN
IN
4.3kΩ
R3
1MΩ
1%
R4
42.2kΩ
1%
Q
Q
C1
1µF
100V
R9
V
OUT
C16
15µF
35V
0.022µF
C14
D
=
C2
1µF
100V



0.22µF
JU1
D8
Q
Q
1
0.22µF
Internal Error Amplifier
C7
C12
+
C9
2200pF
FB_P
R
R
5
6
2
3
1
7



FB
COMP
UVLO/EN
V
CC
V
REF
MAX5052A
R7
1.2kΩ
U1
262kHz WITH 50%
(MAX5052A/MAX5053A)
262kHz WITH 75%
(MAX5052B/MAX5053B)
R12
1.2kΩ
NDRV
GND
OPEN
V
CS
R8
IN
*
8
6
4
5
D7
OPEN
IN
*
C8
OPEN
C11
0.22µF
R10
0Ω
D6
C10
OPEN
100Ω
R11
*
OPEN
D3
4
*
5
L2
1 2
6
where V
is internally connected to a digital soft-start circuit that
gradually increases the reference voltage during start-
up and is applied to this pin. This forces the output volt-
age to come up in an orderly and well-defined manner
under all load conditions.
The error amplifier may also be used to regulate the ter-
tiary winding output which implements a primary-side
regulated, isolated power supply (see Figure 5).
Calculate the output voltage using the following equation:
where N
N
and V
T
7 8
N1
3
5
4
3
2
1
is the number of tertiary winding turns, and both V
R5
0.17Ω
1%
D1
T1
V
REF
S
are the diode drops at the respective outputs.
OUT
10
9
8
7
6
is the number of secondary turns for V
*COMPONENTS MARKED "OPEN" ARE OPTIONAL.
(SEE MAX5052A EV KIT DATA SHEET.)
= 1.23V. The amplifier’s noninverting input
1
=
C6
0.0047µF
250VAC
D2
D1
N
N
S
T






C3
68µF
6.3V
1
C5
47µF
25V
+
R
R
2
1
D4



D5
V
L1
REF
C13
1µF
+
C15
1µF
V
D
6
C4
22µF
6.3V



VOUT2 (+15V/0.1A)
VOUT1 (+5V/1.5A)
−
SGND
SGND
V
D
1
OUT1
D6
,