MAX1703 Maxim, MAX1703 Datasheet - Page 7

• Manufacturer Part Number: MAX1703
• Description: 1-Cell to 3-Cell / High-Power 1.5A / Low-Noise / Step-Up DC-DC Converter
• Manufacturer: Maxim

Dual Mode is a trademark of Maxim Integrated Products.
(V
_________________________________Typical Operating Characteristics (continued)
10, 12
13, 15
IN
PIN
11
14
16
1
2
3
4
5
6
7
8
9
= +3.6V, V
V
PULSE WIDTH = 577 s, LOAD CURRENT = 100mA TO 1A
IN
CLK/SEL
= 3.6V, V
NAME
POKIN
PGND
POUT
GND
OUT
POK
REF
LXN
LXP
AIN
AO
ON
FB
GSM LOAD-TRANSIENT RESPONSE
OUT
OUT
= 5V, T
= 5V, C
_______________________________________________________________________________________
Reference Output. Bypass with a 0.22µF bypass capacitor to GND.
Dual-Mode™ Feedback Input. Connect FB to ground to set a fixed output voltage of +5V. Connect a
divider between the output voltage and GND to set the output voltage from 2.5V to 5.5V.
Power-Good Comparator Input. Threshold is 1.250V, with 1% hysteresis on the threshold’s rising edge.
DC-DC Converter Output. Power source for the IC.
Ground
Gain-Block Input. When AIN is low, AO sinks current. The nominal transconductance from AIN to AO is
10mmhos.
Gain-Block Output. This open-drain output sinks current when V
Power-Good Comparator Output. This open-drain N-channel output is low when V
Switch-Mode Selection and External-Clock Synchronization Input:
Turning on with CLK/SEL = 0V also serves as a soft-start function, since peak inductor current is limited to
25% of that allowed in PWM mode.
Source of N-Channel Power MOSFET Switch
Drain of N-Channel Power Switch. Connect LXP to LXN.
Source of P-Channel Synchronous Rectifier MOSFET Switch. Connect an external Schottky diode from LXN
and LXP to POUT.
Drain of P-Channel Synchronous Rectifier. Connect LXP to LXN.
On/Off Input. When ON is low, the IC turns on.
OUT
CLK/SEL = Low: Low-power, low-quiescent-current PFM mode. Delivers up to 10% of full load current.
CLK/SEL = High: High-power PWM mode. Full output power available. Operates in low-noise, constant-
CLK/SEL = External Clock: High-power PWM mode with the internal oscillator synchronized to the exter-
A
1ms/div
= 470 F,
= +25°C, unless otherwise noted.)
Low-Noise, Step-Up DC-DC Converter
1-Cell to 3-Cell, High-Power (1.5A),
frequency mode.
nal CLK
MAX1703-12
V
(100mV/div)
I
(0.5A/div)
LOAD
OUT
FUNCTION
V
PULSE WIDTH = 416 s, LOAD CURRENT = 50mA TO 400mA
IN
= 1.2V, V
DECT LOAD-TRANSIENT RESPONSE
OUT
AIN
= 3.3V, C
< V
OUT
REF
2ms/div
= 470 F,
.
Pin Description
POKIN
< 1.250V.
MAX1703-13
V
(100mV/div)
I
(0.2A/div)
LOAD
OUT
7