MAX1549 Datasheet, PDF (3/11 Pages) Maxim Integrated Products – MAX1549 Evaluation Kit

MAX1549 Evaluation Kit
Procedure
1) Ensure that the circuit is connected correctly to the
supplies and dummy loads prior to applying any
power.
2) Verify that the shunts are installed across pins 1
and 2 of jumper JU1 (ON1 high), pins 1 and 2 of
jumper JU2 (ON2 high), and pins 1 and 2 of JU6
(SKIP high, forced PWM).
3) Turn on battery power prior to +5V bias power; oth-
erwise, the output UVLO timer times out and the
FAULT latch is set, disabling the regulator outputs
until +5V power is cycled or ON1/ON2 is toggled.
4) Verify that the output voltages are V_OUT1 = 1.5V,
V_OUT2 = 2.5V.
Detailed Description
Jumper Settings
Table 1. Jumper JU1 Functions
(Output Voltage OUT1 Control)
JU1
ON1 PIN
OUT1
1 and 2
(Default) ^{Connected to VCC.}
OUT1 enabled, V_OUT1 =
1.5V. OUT1 depends on
gate inputs G0 and G1.
See Table 4.
2 and 3 Connected to GND. OUT1 shutdown mode
Not
Installed
ON1 must be driven by
an external signal
connected to ON1 pad.
OUT1 operation depends
on the external ON1 signal
levels.
Table 3. Jumpers JU3 Functions
(Switching-Frequency Selection)
JU3
1 and 2
1 and 3
1 and 4
TON PIN
Connected to VCC
Connected to REF
Connected to GND
FREQUENCY (kHz)
400
200
100
Not
Installed
(Default)
Floating
300
(As Shipped)
Note: Do not change the operating frequency without first
recalculating component values. The frequency has a signifi-
cant effect on preferred inductor value, peak current-limit level,
MOSFET heating, PFM/PWM switchover point, output noise,
efficiency, and other critical parameters.
Table 4. Jumpers JU4 and JU5 Functions
(Gate Inputs G0 and G1)
JU4
JU5
OUT1
Not Installed
G0 = GND
Not Installed
G1 = GND
1.50V
(Default)
Installed
G0 = VCC
Not Installed
G1 = GND
1.30V
Not Installed
G0 = GND
Installed
G1 = VCC
1.00V
Installed
G0 = VCC
Installed
G1 = VCC
0.70V
Table 2. Jumper JU2 Functions
(Output Voltage OUT2 Control)
JU2
ON2 PIN
OUT2
1 and 2 _{Connected to VCC.}
(Default)
OUT2 enabled, V_OUT2 =
2.5V
2 and 3 Connected to GND. OUT2 shutdown mode
Not
ON2 must be driven by OUT2 operation depends
an external signal
on the external ON2 signal
Installed _{connected to ON2 pad. levels.}
Table 5. Jumper JU6 Functions
(Low-Noise Mode)
JU6
SKIP PIN
OPERATIONAL
MODE
1 and 2
(Default)
Connected to VCC.
Low-noise mode,
OUT1 and OUT2 are in
forced PWM mode.
2 and 3
Connected to GND. ^{OUT1 and OUT2 are in}
pulse-skipping mode.
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