MAX5027 MAXIM [Maxim Integrated Products], MAX5027 Datasheet

no-image

MAX5027

Manufacturer Part Number
MAX5027
Description
500kHz, 36V Output, SOT23, PWM Step-Up DC-DC Converters
Manufacturer
MAXIM [Maxim Integrated Products]
Datasheet

Available stocks

Company
Part Number
Manufacturer
Quantity
Price
Part Number:
MAX5027EUT+
Manufacturer:
MAXIM
Quantity:
1 000
Part Number:
MAX5027EUT+T
Manufacturer:
MAXIM
Quantity:
2 500
The MAX5025–MAX5028 constant-frequency, pulse-
width modulating (PWM), low-noise boost converters
are intended for low-voltage systems that often need a
locally generated high voltage. These devices are
capable of generating low-noise, high output voltages
required for varactor diode biasing in TV tuners, set-top
boxes, and PCI cable modems. The MAX5025–
MAX5028 operate from as low as 3V and switch at
500kHz.
The constant-frequency, current-mode PWM architec-
ture provides for low output noise that is easy to filter. A
40V lateral DMOS device is used as the internal power
switch, making the devices ideal for boost converters
up to 36V. The MAX5025/MAX5026 adjustable versions
require the use of external feedback resistors to set the
output voltage. The MAX5027/MAX5028 offer a fixed
30V output. These devices are available in a small, 6-
pin SOT23 package.
19-2239; Rev 1; 12/01
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com
V
CC
V
CC
= 4.5V TO 11V
= 3V TO 11V
TV Tuner Power Supply
Low-Noise Varactor Diode Biasing
Set-Top Box Tuner Power Supply
PCI Cable Modem
Voice-Over-Cable
LCD Power Supply
Avalanche Photodiode Biasing
(MAX5027)
(MAX5028)
Typical Operating Circuit
500kHz, 36V Output, SOT23, PWM Step-Up
C1
________________________________________________________________ Maxim Integrated Products
V
SHDN
PGND
General Description
CC
MAX5027
MAX5028
L1
GND
LX
FB
Applications
D1
C2
V
30V
OUT
o Input Voltage Range:
o Wide Output Voltage Range: V
o Output Power: 120mW (max)
o User-Adjustable Output Voltage with
o Fixed 30V Output Voltage: MAX5027/MAX5028
o Internal 1.3Ω (typ), 40V Switch
o Constant PWM Frequency Provides Easy Filtering
o 500kHz (typ) Switching Frequency
o 1µA (max) Shutdown Current
o Small, 6-Pin SOT23 Package
Selector Guide appears at end of data sheet.
MAX5025EUT-T
MAX5026EUT-T
MAX5027EUT-T
MAX5028EUT-T
3V to 11V (MAX5026/MAX5028)
4.5V to 11V (MAX5025/MAX5027)
MAX5025/MAX5026 Using External Feedback
Resistors
in Low-Noise Applications
TOP VIEW
PA RT
DC-DC Converters
PGND
GND
FB
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
RANGE
1
2
3
TEMP.
Ordering Information
SOT23-6
MAX5025–
MAX5028
Pin Configuration
PIN-
PA CKA GE
6 SOT23-6
6 SOT23-6
6 SOT23-6
6 SOT23-6
CC
6
5
4
to 36V
LX
V
SHDN
CC
Features
MARK
AATM
AATK
AATL
AATJ
TOP
1

Related parts for MAX5027

MAX5027 Summary of contents

Page 1

... The MAX5025/MAX5026 adjustable versions require the use of external feedback resistors to set the output voltage. The MAX5027/MAX5028 offer a fixed 30V output. These devices are available in a small, 6- pin SOT23 package. TV Tuner Power Supply ...

Page 2

... GND ............................................................-0.3V to +12V CC PGND to GND .......................................................-0.1V to +0. GND (MAX5025/MAX5026)...............-0. GND (MAX5027/MAX5028)...........................-0.3V to +40V SHDN to GND.............................................-0. GND ..............................................................-0.3V to +45V Peak LX Current ................................................................600mA Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied ...

Page 3

... Note 2: Switch current-limit accuracy is typically ±20% and is a function of the input voltage. I _______________________________________________________________________________________ CONDITIONS MAX5025 4.5V to 11V CC MAX5027 4.5V to 11V MAX5026 3.3V to 11V CC MAX5028 3.3V to 11V CC MAX5025/MAX5026 MAX5027/MAX5028 30V MAX5025/MAX5026 MAX5026/MAX5028 40mA 11V CC I Note 2 LIM ...

Page 4

Output, SOT23, PWM Step-Up DC-DC Converters ( 30V +25°C, unless otherwise noted.) CC OUT A EFFICIENCY vs. LOAD CURRENT (V = 12V) OUT MAX5026 30 V ...

Page 5

Output, SOT23, PWM Step- 5V 30V +25°C, unless otherwise noted.) CC OUT A EXITING SHUTDOWN OUTPUT VOLTAGE 20V/div 5V INDUCTOR CURRENT 50mA/div SHUTDOWN VOLTAGE 5V/div 2ms/div MAX5026 5V ...

Page 6

Output, SOT23, PWM Step-Up DC-DC Converters ( 30V +25°C, unless otherwise noted.) CC OUT A HEAVY-LOAD SWITCHING WAVEFORM WITHOUT RC FILTER V OUT 5mV/div AC-COUPLED LX PIN 20V/div I L 200mA/div 1µs/div ...

Page 7

Output, SOT23, PWM Step- 5V 30V +25°C, unless otherwise noted.) CC OUT A SWITCH ON-RESISTANCE vs. TEMPERATURE 3 1.5 1.0 0.5 -40 ...

Page 8

... The following design discussions are limited to step-up, with a complete circuit shown in the Application Circuits section. The output voltage of the MAX5027/MAX5028 is fixed at 30V. The output voltage of the MAX5025/MAX5026 is set by two external resistors (R1 and R2, Figure 2 and Figure 3). First select the value the 5kΩ to PWM Controller 50kΩ ...

Page 9

Output, SOT23, PWM Step-Up ULVO OSCILLATOR MAIN PWM COMPARATOR CONTROL LOGIC +A REF +C 2 GND -C CURRENT- LIMIT COMPARATOR Figure 1. Functional Diagram   OUT ...

Page 10

Output, SOT23, PWM Step-Up DC-DC Converters For a design in which 4mA, η = 0.5, and T = 2µ 87µH UPPER and L = 12µH. LOWER For a worst-case scenario ...

Page 11

Output, SOT23, PWM Step-Up trace lengths to reduce stray capacitance, trace resis- tance, and radiated noise. The trace between the out- put voltage-divider (MAX5025/MAX5026) and the FB pin must be kept short, as well as the trace between ...

Page 12

... Output, SOT23, PWM Step-Up DC-DC Converters PART OUTPUT MAX5025 Adjustable MAX5026 Adjustable MAX5027 Fixed 30V MAX5028 Fixed 30V 12 ______________________________________________________________________________________ FREQUENCY FB SET POINT TOLERANCE TOLERANCE ±5% -31% to +100% ±3% -18% to +34% ±5% -31% to +100% ±3% -18% to +34% Selector Guide INPUT VOLTAGE 4.5V to 11V 3V to 11V 4 ...

Page 13

Output, SOT23, PWM Step-Up Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications ...

Related keywords