Rainbow Electronics MAX1724 - Manual

General Description
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.
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 0.5
Ω 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).
Applications
Features
♦ Up to 90% Efficiency
♦ No External Diode or FETs Needed
♦ 1.5µA Quiescent Supply Current
♦ 0.1µA Logic-Controlled Shutdown
♦ ±1% Output Voltage Accuracy
♦ Fixed Output Voltage (MAX1724) or Adjustable
Output Voltage (MAX1722/MAX1723)
♦ Up to 150mA Output Current
♦ 0.8V to 5.5V Input Voltage Range
♦ 0.91V Guaranteed Startup (MAX1722/MAX1724)
♦ Internal EMI Suppression (MAX1722/MAX1724)
♦ Thin SOT23-5 Package (1.1mm max Height)
MAX1722/MAX1723/MAX1724
1.5µA I Q , Step-Up DC-DC Converters
in Thin SOT23-5
________________________________________________________________ Maxim Integrated Products 1
GND
OUT FB
1 5 LX BATT
MAX1722
THIN SOT23-5
TOP VIEW
2
3 4
LX
OUT
IN
0.8V TO 5.5V
3.3V AT
UP TO 150mA ON
OFF
BATT
MAX1724
SHDN
GND
10 µH
OUT
Typical Operating Circuit
19-1735; Rev 0; 7/01
Ordering Information
Selector Guide
Pagers
Remote Controls
Remote Wireless
Transmitters
Personal
Medical Devices
Digital Still Cameras
Single-Cell Battery-
Powered Devices
Low-Power Hand-Held
Instruments
MP3 Players
Personal Digital
Assistants (PDA)
Pin Configurations are continued at end of data sheet.
PART
MAX1722EZK
MAX1723EZK
MAX1724EZK27 Fixed 2.7
Adjustable
Adjustable
OUTPUT (V) SHDN
No
Yes
Yes
MAX1724EZK30
MAX1724EZK33
MAX1724EZK50 Fixed 5.0
Fixed 3.3
Fixed 3.0 Yes
Yes
Yes
LX
DAMPING
Yes
No
Yes
Yes
Yes
Yes
ADQK
ADQJ
ADQI
ADQH
ADQG
ADQF
TOP
MARK
5 SOT23
5 SOT23
5 SOT23 -40°C to +85°C
-40°C to +85°C
-40°C to +85°C MAX1724EZK50-T
MAX1724EZK33-T
MAX1724EZK30-T
5 SOT23
5 SOT23
5 SOT23
PIN-
PACKAGE
TEMP. RANGE
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C MAX1724EZK27-T
MAX1723EZK-T
MAX1722EZK-T
PART
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.
Pin Configurations