MAX1972EEE+ Maxim Integrated Products, MAX1972EEE+ Datasheet - Page 12

• Manufacturer Part Number: MAX1972EEE+
• Description: IC REG STP DWN 750MA 16-QSOP
• Manufacturer: Maxim Integrated Products
• Type: Step-Down (Buck)r

Specifications of MAX1972EEE+

• Internal Switch(s): Yes
• Synchronous Rectifier: Yes
• Number Of Outputs: 2
• Voltage - Output: 1.5V, 1.8V, 2.5V, 3.3V, Adj
• Current - Output: 750mA
• Frequency - Switching: 1.4MHz
• Voltage - Input: 2.6 ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 16-QSOP
• Power - Output: 667mW
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

turns off and the internal low-side n-channel MOSFET
turns on. Now the inductor releases the stored energy
as its current ramps down while still providing current to
the output. The output capacitor stores charge when
the inductor current exceeds the load current and dis-
charges when the inductor current is lower, smoothing
the voltage across the load. Under overload conditions,
when the inductor current exceeds the current limit (see
the Current Limit section), the high-side MOSFET is not
Dual, 180° Out-of-Phase, 1.4MHz, 750mA Step-
Down Regulator with POR and RSI/PFO
Figure 1. Functional Diagram
12
FBSEL1
COMP1
COMP2
FBSEL2
______________________________________________________________________________________
FB1
REF
FB2
EN
IN
V
GND
CC
THERMAL SHUTDOWN
SOFT-START
SELECT
VOK
FB
REFERENCE
VOLTAGE
1.2V
REGULATOR 2
CLAMP
CURRENT SENSE
ERROR SIGNAL
SLOPE COMP
turned on at the rising edge of the clock and the low-
side MOSFET remains on to let the inductor current
ramp down.
The current-sense circuit amplifies the current-sense
voltage generated by the high-side MOSFET’s on-resis-
tance and the inductor current (R
This amplified current-sense signal and the internal
slope compensation signal are summed together into
REGULATOR 1
÷2(MAX1970/
÷4(MAX1971)
MAX1972)/
PWM CONTROL
MAX1970/MAX1972 ONLY
OSCILLATOR
MAX1970
MAX1971
MAX1972
2.8MHz
POR
PFO
DS(ON)
Current Sense
MAX1971 ONLY

I
RSI
INDUCTOR
LX1
PGND
POR
PFO
).