MAX1531EVKIT Maxim Integrated Products, MAX1531EVKIT Datasheet - Page 9

• Manufacturer Part Number: MAX1531EVKIT
• Description: Power Management Modules & Development Tools MAX1531 EVAL KIT MAX1531 EVAL KIT
• Manufacturer: Maxim Integrated Products

Specifications of MAX1531EVKIT

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

The MAX1531 EV kit’s gate-on linear regulator output
(GON) is set to +25V by feedback resistors R25 and
R26. To generate output voltages other than +25V (from
+1.24V up to the linear regulator’s input, which is the
output of the positive charge pump), select different
external voltage-divider resistors (R25, R26). Take care
not to exceed either the pnp pass transistor’s V
ing (40V) or the output capacitor’s (C16) +50V rating.
Before GON is enabled, Q3 is off and the positive
charge pump’s full output voltage is present across Q3.
If the input voltage (PIN) exceeds 13.2V, do not power
the EV kit with the charge pump configured as a two-
stage charge pump powered from PIN, as Q3’s 40V
rating will be exceeded. Configure JU12 and JU13 for a
two-stage charge pump powered from VOUT or as a
one-stage charge pump powered from PIN, whichever
is appropriate. Alternatively, select a different transistor
for Q3 and possibly Q6, which must withstand the
same voltage, minus V
a one-stage charge pump will exceed +40V, so either
change Q3 or disable the charge pump entirely and
power the linear regulator directly from PIN, whichever
is appropriate.
Refer to the Linear-Regulator Controllers Output
Voltage Selection section in the MAX1531 data sheet
for instruction on selecting the voltage-divider resistors.
Also, refer to the Charge Pumps section for more infor-
mation about configuring the positive charge pump.
Gate-On Linear Regulator Output
_______________________________________________________________________________________
PIN
. If V
PIN
exceeds +20V, even
Voltage (GON)
CEO
rat-
MAX1531 Evaluation Kit
The MAX1531 EV kit’s source-supply linear regulator
output (VSRC) is set to +10V by feedback resistors R22
and R23. To generate output voltages other than +10V
(from +1.24V up to its input voltage) select different
external voltage-divider resistors (R22, R23). Output
capacitor C13 is rated to +16V. To set the output volt-
age greater than +16V, use a higher-voltage-rated
capacitor. Refer to the Linear-Regulator Controllers
Output Voltage Selection section in the MAX1531 data
sheet for instructions on selecting the resistors.
The MAX1531 EV kit’s negative linear regulator output
(GOFF) is set to -9V by feedback resistors R28 and
R29. To generate output voltages other than -9V (0V
down to its input voltage), select different external volt-
age-divider resistors (R28, R29). Output capacitor C19
is rated to -16V. To set the output voltage below -16V,
use a higher-voltage-rated capacitor. Refer to the
Linear-Regulator Controllers Output Voltage Selection
and Charge Pumps sections in the MAX1531 data
sheet for instructions on selecting the resistors.
The MAX1531 EV kit can also evaluate the MAX1530.
To evaluate the MAX1530, replace U1 with the
MAX1530. Refer to the MAX1530/MAX1531 data sheets
for additional information.
Source-Supply Linear Regulator Output
Gate-Off Linear Regulator Output
Evaluating the MAX1530
Voltage (VSRC)
Voltage (GOFF)
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