19-1735; Rev 0; 7/01
1.5µA I , Step-Up DC-DC Converters
Q
in Thin SOT23-5
General Description
Features
The MAX1722/MAX1723/MAX1724 compact, high-effi-
ciency, step-up DC-DC converters are available in tiny, 5-
pin thin SOT23 packages. They feature an extremely low
1.5µA quiescent supply current to ensure the highest pos-
sible light-load efficiency. Optimized for operation from
one to two alkaline or nickel-metal-hydride (NiMH) cells, or
a single Li+ cell, these devices are ideal for applications
where extremely low quiescent current and ultra-small size
are critical.
o Up to 90% Efficiency
o No External Diode or FETs Needed
o 1.5µA Quiescent Supply Current
o 0.1µA Logic-Controlled Shutdown
o
1% ꢀutput ꢁoltage Accuracy
o Fixed ꢀutput ꢁoltage (MAX1724) or Adjustable
ꢀutput ꢁoltage (MAX1722/MAX1723)
o Up to 150mA ꢀutput Current
Built-in synchronous rectification significantly improves
efficiency and reduces size and cost by eliminating the
need for an external Schottky diode. All three devices fea-
ture a 0.5Ω N-channel power switch. The MAX1722/
MAX1724 also feature proprietary noise-reduction circuitry,
which suppresses electromagnetic interference (EMI)
caused by the inductor in many step-up applications. The
family offers different combinations of fixed or adjustable
outputs, shutdown, and EMI reduction (see Selector
Guide).
o 0.8ꢁ to 5.5ꢁ Input ꢁoltage Range
o 0.91ꢁ Guaranteed Startup (MAX1722/MAX1724)
o Internal EMI Suppression (MAX1722/MAX1724)
o Thin SꢀT23-5 Package (1.1mm max Height)
Ordering Information
PIN-
TꢀP
PART
TEMP. RANGE
PACKAGE MARK
MAX1722EZK-T
MAX1723EZK-T
MAX1724EZK27-T
MAX1724EZK30-T
MAX1724EZK33-T
MAX1724EZK50-T
-40°C to +85°C 5 SOT23
-40°C to +85°C 5 SOT23
-40°C to +85°C 5 SOT23
-40°C to +85°C 5 SOT23
-40°C to +85°C 5 SOT23
-40°C to +85°C 5 SOT23
ADQF
ADQG
ADQH
ADQI
Applications
Pagers
Single-Cell Battery-
Powered Devices
Remote Controls
ADQJ
ADQK
Low-Power Hand-Held
Instruments
Remote Wireless
Transmitters
MP3 Players
Personal
Medical Devices
Selector Guide
Personal Digital
Assistants (PDA)
LX
DAMPING
Digital Still Cameras
PART
ꢀUTPUT (ꢁ)
SHDN
MAX1722EZK
Adjustable
Adjustable
Fixed 2.7
Fixed 3.0
Fixed 3.3
Fixed 5.0
No
Yes
No
MAX1723EZK
Yes
Yes
Yes
Yes
Yes
MAX1724EZK27
MAX1724EZK30
MAX1724EZK33
MAX1724EZK50
Yes
Yes
Yes
Yes
Typical Operating Circuit
Pin Configurations
10µH
TOP VIEW
IN
BATT
LX
0.8V TO 5.5V
BATT
GND
FB
1
2
3
5
LX
MAX1724
MAX1722
OUT
OUT
ON
3.3V AT
UP TO 150mA
SHDN
OFF
4
OUT
GND
THIN SꢀT23-5
Pin Configurations are continued at end of data sheet.
________________________________________________________________ Maxim Integrated Products
1
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.