MAX16050ETI+T Maxim Integrated Products, MAX16050ETI+T Datasheet - Page 16

• Manufacturer Part Number: MAX16050ETI+T
• Description: IC POWER MONITR/SEQUENCER 28TQFN
• Manufacturer: Maxim Integrated Products

Specifications of MAX16050ETI+T

• Applications: Power Supply Monitor, Sequencer
• Voltage - Supply: 2.7 V ~ 13.2 V
• Current - Supply: 700µA
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 28-TQFN Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Input: -

Voltage Monitors/Sequencer Circuits with
Reverse-Sequencing Capability
When EN_HOLD is low, a high-to-low transition on
SHDN or on EN is ignored. EN_HOLD must be high for
SHDN or EN to disable the device. This feature is used
when multiple MAX16050/MAX16051s are daisy-
chained (see Figure 7). Connect EN_HOLD to ABP if
not used.
Connect a capacitor (C
GND to adjust the sequencing delay period (t
that occurs between sequenced channels. Use the fol-
lowing formula to estimate the delay:
where t
Leave DELAY unconnected for the default 10µs (typ)
delay.
Connect a capacitor (C
GND to set the reset timeout period. After all SET_
inputs exceed their thresholds (V
low for the programmed timeout period, t
deasserting (see Figure 1). Use the following formula to
estimate the reset timeout period:
where t
Leave TIMEOUT unconnected for the default 10µs (typ)
timeout delay or connect TIMEOUT to ABP to enable a
fixed 128ms (typ) timeout.
The MAX16050/MAX16051 feature four and five SET_
inputs, respectively, and the threshold voltage (V
each SET_ input is 0.5V (typ). To monitor a voltage
V
as shown in Figure 6, and use the following equation to
calculate the monitored threshold voltage:
Balance accuracy and power dissipation when choos-
ing the external resistors. The input to the voltage moni-
tor is a high-impedance input with a small 100nA
leakage current. This leakage current contributes to the
overall error of the threshold voltage, and this error is
proportional to the value of the resistors used to set the
threshold. Small-valued resistors reduce the error but
increase the power consumption. Use the following
16
1TH
______________________________________________________________________________________
, connect a resistive divider network to the circuit
DELAY
RP
t
DELAY
t
is in seconds and C
RP
Reset Timeout Input (TIMEOUT)
= 10µs + (500kΩ x C
is in seconds and C
Applications Information
V
Enable Hold Input ( EN_HOLD )
= 10µs + (500kΩ x C
1TH
Delay Time Input (DELAY)
=
Resistor Value Selection
V
DELAY
TH
TIMEOUT
×
⎛
⎜
⎝
1
) between DELAY and
+
TIMEOUT
R2
R1
TH
) from TIMEOUT to
TIMEOUT
DELAY
), RESET remains
⎞
⎟
⎠
DELAY
is in Farads.
is in Farads.
)
)
RP
, before
DELAY
TH
) at
)
equation to estimate the value of the resistors based on
the amount of acceptable error:
where e
absolute resistive divider error attributable to the input
leakage current (use 0.01 for ±1%), V
good threshold for the power supply being monitored,
and I
(see the Electrical Characteristics table). Calculate R2
as follows:
The exact value of the pullup resistors for the open-
drain outputs is not critical, but some consideration
should be made to ensure the proper logic levels when
the device is sinking current. For example, if V
3.3V and the pullup voltage is 5V, keep the sink current
less than 3.2mA as shown in the Electrical
Characteristics table. As a result, the pullup resistor
should be greater than 1.6kΩ. For a 13.2V pullup, the
resistor should be larger than 4.1kΩ.
Extra care must be taken when using CP_OUT as the
pullup voltage. If multiple pullup resistors are connect-
ed to CP_OUT and one or more of the connected OUT_
outputs are asserted, the current drawn can drop the
CP_OUT voltage enough to prevent an enabled
MOSFET from turning on completely.
Figure 6. Setting the SET_ Input
SET
R1
R2
A
V
1TH
is the worst-case SET_ input leakage current
is the fraction of the maximum acceptable
R2
R1
SET_
=
=
V
e
1TH
V
Pullup Resistor Values
A
TH
MAX16050
MAX16051
I
SET
×
V
GND
−
V
V
×
BUS
CC
1TH
V
R
TH
1
RESET
1TH
is the power-
CC
=