MAX8794ETB+T Maxim Integrated Products, MAX8794ETB+T Datasheet - Page 10

• Manufacturer Part Number: MAX8794ETB+T
• Description: IC DDR LINEAR REG 10-TDFN
• Manufacturer: Maxim Integrated Products

Specifications of MAX8794ETB+T

• Applications: Converter, DDR
• Voltage - Input: 1.1 ~ 3.6 V
• Number Of Outputs: 1
• Voltage - Output: 0.5 ~ 1.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 10-TDFN Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Low-Voltage DDR Linear Regulator
The MAX8794 provides an open-drain PGOOD output
that goes high 2ms (typ) after the output initially reach-
es regulation during startup. PGOOD transitions to low
after a 10µs delay when either the output goes out of
regulation by ±150mV, or when the device enters shut-
down. Connect a pullup resistor from PGOOD to V
for a logic-level output. Use a 100kΩ resistor to mini-
mize current consumption.
By changing the voltage at REFIN, the MAX8794 can
be used in applications that require dynamic output-
voltage changes between two set points (graphics
processors). Figure 4 shows a dynamically adjustable
resistive voltage-divider network at REFIN. Using an
external signal MOSFET, a resistor can be switched in
and out of the REFIN resistor-divider, changing the volt-
age at REFIN. The two output voltages are determined
by the following equations:
Figure 3. MAX8794 PGOOD and Soft-Start Waveforms
10
______________________________________________________________________________________
V
CURRENT LIMIT
Dynamic Output-Voltage Transitions
POWER-GOOD
OUT HIGH
V
WINDOW
OUT LOW
PGOOD
(
SHDN
OUT
Applications Information
(
)
=
)
V
=
REF
V
200μs
Power-Good (PGOOD)
REF
⎡
⎢
⎢
⎣
R
2ms STARTUP
1
⎛
⎜
⎝
DELAY
(
R
+
R
1
2
(
R
+
R
+
2
2
R
R
3
+
2
)
R
⎞
⎟
⎠
3
)
⎤
⎥
⎥
⎦
PROPAGATION
CC
DELAY
10μs
Figure 4. Dynamic Output-Voltage Change
OUTPUT OVERLOAD
CONDITION
V
V
OUT(LOW)
OUT(HIGH)
V
OUT(HIGH)
= V
=
V
REF
REF
10μs
PROPAGATION
DELAY
( )
V
R1 + (R2 + R3)
R1 + R2
OUT(LOW)
R2
(R2 + R3)
C
REFIN
REFERENCE
R1
R2
R3
VOLTAGE
(V
REF
)
REFIN
MAX8794