MAX1947ETA30+T Maxim Integrated Products, MAX1947ETA30+T Datasheet - Page 8

• Manufacturer Part Number: MAX1947ETA30+T
• Description: IC DC-DC CONV 3V 8-TDFN
• Manufacturer: Maxim Integrated Products
• Type: Step-Up (Boost)r

Specifications of MAX1947ETA30+T

• Internal Switch(s): Yes
• Synchronous Rectifier: Yes
• Number Of Outputs: 1
• Voltage - Output: 3V
• Current - Output: 250mA
• Frequency - Switching: Up to 2MHz
• Voltage - Input: 0.7 ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 8-TDFN Exposed Pad
• Power - Output: 1.95W
• Output Voltage: 3 V
• Output Current: 185 mA
• Input Voltage: 0.7 V to 3.6 V
• Supply Current: 70 uA
• Switching Frequency: 650 KHz
• Mounting Style: SMD/SMT
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: MAX1947ETA30+T

The MAX1947 enters shutdown mode when SHDN is
driven low. During shutdown, the synchronous rectifier
disconnects the output from the input, eliminating the DC
conduction path that normally exists with traditional boost
converters in shutdown mode. The output is actively dis-
charged to ground through an internal 500Ω resistor. The
quiescent current is reduced to 2µA while in shutdown
mode. Drive SHDN high for normal operation. The output
reaches regulation approximately 650µs after SHDN
goes high.
An inductor value of 4.7µH performs well in most appli-
cations. The MAX1947 also works with inductors in the
2.2µH to 6.8µH range. Smaller inductance values typi-
Low Input/Output Voltage
Step-Up DC-DC Converter with RESET
Table 1. Suggested Component Values
Table 2. Suggested Component Manufacturers
8
Sumida
Taiyo Yuden
TDK
MANUFACTURER
_______________________________________________________________________________________
APPLICATION
Output < 2.7V
Output > 2.7V
1-Cell Input,
1-Cell Input,
2-Cell Input
Applications Information
Output capacitors
Output capacitors
Input capacitors
Input capacitors
>50% full load
>50% full load
>50% full load
≤50% full load
≤50% full load
≤50% full load
Inductor
PART
LOAD
Inductor Selection
INPUT CAPACITOR (µF)
Shutdown
4.7µF JMK212BJ475MG,
4.7µF C2012X5R0J475K,
2.2µF C1608X5R03225M
2.2µF LMK107BJ225MA
10µF JMK212BJ106MG
10µF C2012X5R0J106K
CDRH3D16 series
PART NUMBER
2.2
2.2
2.2
2.2
2.2
2.2
cally offer a smaller physical size for a given series
resistance, allowing the smallest overall circuit dimen-
sions but with lower output-current capability. Circuits
using larger inductance values exhibit higher output-
current capability, but are larger for the same series
resistance and current rating.
The inductor’s incremental saturation current rating should
be greater than the peak switch-current limit. However, it
is generally acceptable to bias the inductor into saturation
by as much as 20%, although this slightly reduces
efficiency (see the Electrical Characteristics for the
MAX1947 NFET current limit). Table 1 lists the suggested
components for several typical applications. Also, the
inductor’s DC resistance significantly affects efficiency.
Table 2 lists suggested component manufacturers.
OUTPUT CAPACITOR (µF)
81-3-3667-3381
408-573-4150
888-835-6646
4.7
4.7
4.7
10
10
10
PHONE
www.sumida.com
www.t-yuden.com
www.TDK.com
INDUCTOR (µH)
WEBSITE
3.3
3.3
4.7
4.7
6.8
6.8