MAX1778EVKIT Maxim Integrated Products, MAX1778EVKIT Datasheet - Page 4

• Manufacturer Part Number: MAX1778EVKIT
• Description: Power Management Modules & Development Tools MAX1778 EVAL KIT MAX1778 EVAL KIT
• Manufacturer: Maxim Integrated Products

Specifications of MAX1778EVKIT

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

age divider. Select different external voltage-divider resis-
tors (R10, R11) to generate output voltages other than +4V
(+1.2V to +(V
Selection section in the MAX1778/MAX1880–MAX1885
data sheet for instructions on selecting the resistors. The
V
next to the V
noise coupling.
The MAX1778 EV kit features a built-in transient load
tester for the step-up switching regulator. Connect a
square-wave function generator (50Ω output) to the
TRANS_LOAD and GND pads. Set the frequency and
duty cycle as required. Note that varying the function
generator output voltage (2.0V typ to 10V max) will vary
the gate drive and thus will vary the amount of load
connected to V1. Set the low and high voltage of the
square-wave output according to the desired low- and
high-load currents. Load currents can be calculated by
measuring the voltage at the CSEN pad (across R18,
1Ω) and GND. Divide the measured voltage by 1Ω to
obtain the actual load current.
The MAX1778 EV kit’s fault-trip level for the step-up
switching regulator and the positive charge pump is con-
figured for a +1.1V (0.67
level. To reconfigure the EV kit for other fault-trip levels
(+0.84V to +1.09V), select different external voltage-
divider resistors (R12, R13). Refer to the Fault-Trip Level
(FLTSET) section in the MAX1778/MAX1880–MAX1885
data sheet for instructions on selecting the resistors.
MAX1778 Evaluation Kit
Table 2. Component List for Evaluating Other Linear Regulators
4
COM
_______________________________________________________________________________________
LDO Output Voltage
LDO Output Current
Q1 (external NPN)
buffer has a separate analog ground pad (GND)
DESIGNATOR
(LDOOUT)
(LDOOUT)
C14
C27
C29
R14
R15
R16
R19
COM
C3
SUPB
buffer output (BUFOUT) to reduce any
Transient Performance
- 1.2V)). Refer to the Output Voltage
Faults and Maximizing
✕
V
Transient Load Tester
REF
to 0.87
(V1 set to 8V)
Not installed
Not installed
Not installed
Not installed
Fault-Trip Level
CASE 1
51.1kΩ
+7.6V
40mA
3.3µF
10kΩ
13kΩ
0Ω
✕
V
REF
) fault-trip
(V1 set to 13V)
+9V to +12.4V
60kΩ to 89kΩ
Not installed
Not installed
Not installed
Not installed
CASE 2
40mA
2.2µF
10kΩ
13kΩ
0Ω
Maximizing Transient Performance
The MAX1778 EV kit features several surface-mount,
unpopulated PC board pads for installing feedback
compensation components (R7, C19, C20). To maxi-
mize the transient load performance, remove capacitor
C8, connect the INTG pin (pin 2) to the REF pin (pin 9)
of IC U1, and remove resistor R7 and capacitor C19.
Refer to the Feedback Compensation section in the
MAX1778/MAX1880–MAX1885 data sheet for instruc-
tions on selecting other resistors and capacitors.
The MAX1778 EV kit can be reconfigured for evaluating
the MAX1880, MAX1881, and MAX1882 ICs. U1
(MAX1778) must be removed and replaced with the
new IC (24-pin TSSOP package). The linear regulator
will not function when evaluating a MAX1880 or
MAX1882. Refer to the MAX1778/MAX1880–MAX1885
IC data sheet for information on the various step-up
switching frequency and LDO features.
The MAX1778 EV kit can be reconfigured for evaluating
other linear regulator voltages and currents. Several
components must be replaced to obtain higher volt-
ages or currents. Table 2 lists the components to
replace.
Different Linear Regulator
300mA to 500mA
Evaluating Other ICs and
D-PAK (MJD31)
Not installed
CASE 3
16.5kΩ
4.02kΩ
0.01µF
0.01µF
+3.3V
1.0µF
1.0µF
10kΩ
Linear Regulator Voltages
Evaluating a MAX1880,
MAX1881, or MAX1882
Configurations
SOT23 (2N2222A)
Not installed
CASE 4
3.01kΩ
200mA
0.01µF
0.01µF
+2.5V
1.0µF
1.0µF
10kΩ
10kΩ