MAX1760EUB+T Maxim Integrated Products, MAX1760EUB+T Datasheet - Page 7

• Manufacturer Part Number: MAX1760EUB+T
• Description: IC DC-DC CONV STP UP 10-UMAX
• Manufacturer: Maxim Integrated Products
• Type: Step-Up (Boost)r

Specifications of MAX1760EUB+T

• Internal Switch(s): Yes
• Synchronous Rectifier: Yes
• Number Of Outputs: 1
• Voltage - Output: 3.3V, 2.5 ~ 5.5 V
• Current - Output: 800mA
• Frequency - Switching: 1MHz
• Voltage - Input: 0.7 ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 10-MSOP, Micro10™, 10-uMAX, 10-uSOP
• Power - Output: 444mW
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

The MAX1760 is a highly efficient, low-noise power sup-
ply for portable RF and hand-held instruments. It com-
bines a boost switching regulator, N-channel power
MOSFET, P-channel synchronous rectifier, precision
reference, and shutdown control (Figure 1).
The DC-DC converter boosts a 1-cell to 3-cell battery
voltage input to a fixed 3.3V or adjustable voltage
between 2.5V and 5.5V. An external Schottky diode is
required for output voltages greater than 4V. The
MAX1760 guarantees startup with an input voltage as
low as 1.1V and remains operational down to an input
of just 0.7V. It is optimized for use in cellular phones
and other applications requiring low noise and low qui-
escent current for maximum battery life. It features
fixed-frequency operation at medium and heavy loads,
but at light loads, switches only as needed for optimum
efficiency. This device is also capable of constant-fre-
quency (1MHz), low-noise PWM operation at all load
currents, or frequency-synchronized PWM operation
when connected to an external clock. Table 1 lists
some typical outputs. Shutdown reduces quiescent cur-
rent to just 1µA. Figure 2 shows the standard applica-
tion circuit for the MAX1760.
Figure 1. Functional Diagram
(MAX1760H)
(MAX1760)
CLK/SEL
OUT
GND
ISET
REF
FB
ON
ON
_______________________________________________________________________________________
2.15V
IC POWER
Detailed Description
MAX1760
1.25V
ON
REF
REFERENCE
UNDERVOLTAGE LOCKOUT
GND
RDY
Step-Up DC-DC Converter
CLK/SEL
EN
0.8A, Low-Noise, 1MHz,
EN
During DC-DC converter operation, the internal N-chan-
nel MOSFET switch turns on for the first part of each
cycle, allowing current to ramp up in the inductor and
store energy in a magnetic field. During the second
part of each cycle, the MOSFET turns off and inductor
current flows through the synchronous rectifier to the
Figure 2. Standard Application Circuit
OSCILLATOR
V
1MHz
IN
OSCILLATOR
= 2.4V
STARTUP
MODE
OSC
0.22 F
Q
33 F
CLK/SEL
REF
ON
ISET
D
EN
OSC
MODE
FB
FB
CONTROLLER
MAX1760
3.3 H
GND
ISET
PGND
POUT
OUT
LX
Step-Up Converter
PCH
NCH
4.7
0.68 F
POUT
LX
PGND
100 F
V
800mA
OUT
= 3.3V,
7