MAX8688BLETG+ Maxim Integrated Products, MAX8688BLETG+ Datasheet - Page 27

• Manufacturer Part Number: MAX8688BLETG+
• Description: IC PWR SUPPLY CTRLR/MONTR 24TQFN
• Manufacturer: Maxim Integrated Products

Specifications of MAX8688BLETG+

• Applications: Power Supply Controller/Monitor
• Voltage - Supply: 3 V ~ 3.6 V
• Current - Supply: 6.7mA
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 24-TQFN Exposed Pad
• Supply Voltage (max): 3.6 V
• Supply Voltage (min): 3 V
• Operating Temperature Range: - 40 C to + 85 C
• Mounting Style: SMD/SMT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Input: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

The VOUT_COMMAND command loads the MAX8688
with the voltage to which the POL output is to be
changed when it is commanded to turn on using the
OPERATION command or A3/ONOFF transition when
enabled. Once the POL is turned on, changing the
VOUT_COMMAND has no effect on the POL output
voltage. The MAX8688 only adjusts the POL to the new
VOUT_COMMAND voltage after receiving a new turn-
on command.
The 2 data bytes are in DIRECT format. Valid values are
from 0 to 2.048V when the input range is 2.048V and 0
to 5.5V when the input range is 5.5V.
The default VOUT_COMMAND value is 00h.
The VOUT_MARGIN_HIGH command loads the
MAX8688 with the voltage to which the POL output is to
be changed when the OPERATION command is set to
margin high. If the POL is already operating at margin
high, changing VOUT_MARGIN_HIGH has no effect on
the output voltage. The MAX8688 only adjusts the POL
to the new VOUT_MARGIN_HIGH voltage after receiv-
ing a new margin high OPERATION command.
The 2 data bytes are in DIRECT format. Valid values are
the same as VOUT_COMMAND.
The default VOUT_MARGIN_HIGH value is 00h.
The VOUT_MARGIN_LOW command loads the
MAX8688 with the voltage to which the POL output is to
be changed when the OPERATION command is set to
margin low. If the POL is already operating at margin
low, changing VOUT_MARGIN_LOW has no effect on
the output voltage. The MAX8688 only adjusts the POL
to the new VOUT_MARGIN_LOW voltage after receiv-
ing a new margin low OPERATION command.
The 2 data bytes are in DIRECT format. Valid values are
the same as VOUT_COMMAND.
The default VOUT_MARGIN_LOW value is 00h.
The VOUT_TRANSITION_RATE command sets the rate in
mV/µs at which the POL output voltage should change
when the POL is commanded to change between the
margin high, margin low, and margin off (ON) OPERA-
TION mode. This commanded rate of change does not
apply when the POL is commanded to turn on or turn off.
In that case, t
The 2 data bytes are in DIRECT format. Valid values are
from 0 to 128mV/µs.
The default VOUT_TRANSITION_RATE value is 0mV/µs.
ON_RISE
VOUT_TRANSITION_RATE (27h)
______________________________________________________________________________________
Digital Power-Supply Controller/Monitor
VOUT_MARGIN_HIGH (25h)
and t
VOUT_MARGIN_LOW (26h)
VOUT_COMMAND (21h)
OFF_FALL
applies.
When VOUT_TRANSITION_RATE is cleared to 0,
VOUT_TRANSITION_RATE is ignored and the voltage out-
put is not changed even when commanded by the OPER-
ATION commands. When VOUT_TRANSITION_RATE is
set to 07FFFh, the voltage output is adjusted as quickly
as possible. If a VOUT_TRANSITION_RATE parameter
results in the DAC outputting an out of range value (valid
range 0 to 4090) during transition, the CML flag is set
and FLT is asserted to issue a warning.
The VOUT_TRANSITION_RATE command applies to
REFIN mode only and is ignored in feedback mode.
In a typical application, the output voltage of a power
converter is sensed through a resistive voltage-divider,
as illustrated in Figure 16. The resistive voltage-divider
reduces or scales the output voltage, V
The PMBus commands specify the actual POL output
voltages and not the input voltage to the control circuit.
To allow the MAX8688 to map between the command-
ed voltage (such as 3.3V) and the voltage at the control
circuit input (perhaps 3.3V divided down to match a
reference voltage of 2.0V), the VOUT_SCALE_LOOP
command is used.
The 2 data bytes are in DIRECT format. Valid values are
from 0 to 1.0. Note that due to m, b, R representation
restriction, the supplied value is rounded off to multi-
ples of 1/128. Therefore, to ensure optimum operation,
circuit design should choose a value as close to multi-
ples of 1/128 as possible to avoid rounding errors and
thus ensure the final accuracy of V
This value is dimensionless.
The default VOUT_SCALE_LOOP value is 00h.
The VOUT_SCALE_LOOP command is ignored in feed-
back mode.
Figure 16. VOUT_SCALE_LOOP
with PMBus Interface
MAX8688
VOUT SCALE LOOP
_
RS-
RS+
VOUT_SCALE_LOOP (29h)
_
R2
R1
OUT
=
R
1
.
OUT
R
+
2
VO+
R
2
.
LOAD
POL
VO-
27