19-2499; Rev 0; 7/02
MAX1999 Evaluation Kit
General Description
The MAX1999 evaluation kit (EV kit) demonstrates the
MAX1999’s standard application circuit. This DC-DC con-
verter steps down high-voltage batteries and/or AC
adapters, generating system supplies for notebook com-
puters. The MAX1999 EV kit provides dual 5V and 3.3V
output voltages from a 7V to 24V battery input range. It
delivers up to 5A output current for the 5V output and 5A
for the 3.3V output with greater than 90% efficiency. The
EV kit operates at 200kHz/300kHz switching frequency
(5V/3.3V, respectively) and has superior line-and-load-
transient response.
This EV kit is a fully assembled and tested circuit board. It
allows the evaluation of other output voltages in the 2V to
5.5V range by changing feedback resistors R1–R4.
This EV kit can also be used to evaluate the MAX1777
(200kHz/5.0V SMPS and 300kHz/3.3V SMPS) and the
MAX1977 (400kHz/5.0V SMPS and 500kHz/3.3V SMPS).
o
7V to 24V Input Voltage Range
o
3.3V and 5V Output Voltages
o
2V to 5.5V Adjustable Outputs (External Resistors)
o
5A Output Current (3.3V Output)
o
5A Output Current (5V Output)
o
No Current-Sense Resistor Needed (MAX1999)
o
Accurate Current Sense with Current-Sense
Resistor (MAX1777/MAX1977)
o
200kHz/300kHz Switching Frequency (5V/3.3V,
Respectively)
o
Power-Good (PGOOD) Output
o
Fault Protection Enable/Disable
o
28-Pin QSOP Package
o
Low-Profile Components
o
Fully Assembled and Tested
Features
Evaluates: MAX1777/MAX1977/MAX1999
Ordering Information
PART
MAX1999EVKIT
TEMP RANGE
0
o
C to +70
o
C
IC PACKAGE
28 QSOP
Note:
To evaluate the MAX1777/MAX1977, request a
MAX1777EEI/MAX1977EEI free sample with the MAX1999EVKIT.
Component List
DESIGNATION QTY
C1, C2, C3
C4
C5, C7
C6
3
0
0
1
DESCRIPTION
10µF, 25V ceramic capacitors (1812)
Taiyo Yuden TMK432BJ106KM or
TDK C4532X5R1E106M
Not installed (1812)
Not installed, D case
470µF, 4V, 40mΩ, low-ESR capacitor,
D case
Sanyo 4TPB470M
330µF, 6.3V, 40mΩ, low-ESR
capacitor, D case
Sanyo 6TPB330M
0.1µF ceramic capacitors (0805)
1µF, 10V X5R ceramic capacitors
(0805)
Taiyo Yuden LMK212BJ105KG or
TDK C2012X5R105M
C17
1
DESIGNATION QTY
C13, C14
C16
0
1
DESCRIPTION
Not installed
0.22µF, 16V X5R ceramic capacitor
(0805)
Taiyo Yuden EMK212BJ224KG
4.7µF, 35V tantalum capacitor, C case
Sprague 595D475X0035C2B
4.7µF, 16V tantalum capacitors,
A case
Sprague 595D475X0016A2B
100mA, 30V dual Schottky diode
Central Semiconductor CMPSH-3A
1A, 30V Schottky diodes
Nihon EP10QY03
Toshiba CRS02
3-pin headers
4-pin headers
C18, C19
2
C8
C9, C10, C12,
C15
1
D1
1
4
D2, D3
JU1, JU2
JU3, JU5
2
2
2
C11, C24
2
________________________________________________________________
Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
MAX1999 Evaluation Kit
Evaluates: MAX1777/MAX1977/MAX1999
Component List (continued)
DESIGNATION QTY
L1
L2
1
1
DESCRIPTION
7.6µH, 5.9A power inductor
Sumida CDRH127-7R6
4.7µH, 5.7A power inductor
Sumida CDRH124-4R7
N-channel MOSFET, 8-pin SO
International Rectifier IRF7807V or
Fairchild FDS6612A
N-channel MOSFET, 8-pin SO
International Rectifier IRF7811AV or
Fairchild FDS6670A
Not installed (0805)
Not installed, short PC trace (0805)
3.9Ω
±5%
resistor (1206)
DESIGNATION QTY
R6
R7, R9
R8, R18
R15, R16
R17
U1
None
None
None
None
None
1
2
2
0
1
1
4
4
1
1
1
DESCRIPTION
100kΩ
±5%
resistor (0805)
1MΩ
±5%
resistors (0805)
10Ω
±5%
resistors (0805)
Not installed, short PC trace (2010)
47Ω
±5%
resistor (0805)
MAX1999EEI, 28-pin QSOP
Shunts (JU1, JU2, JU3, JU5)
Rubber feet
MAX1999 PC board
MAX1999 data sheet
MAX1999 EV kit data sheet
N1, N3
2
N2, N4
R1, R3,
R10–R14
R2, R4
R5
2
0
0
1
Component Suppliers
SUPPLIER
Central Semiconductor
Fairchild
International Rectifier
Nihon
Sanyo
Sprague/Vishay
Sumida
Taiyo Yuden
TDK
PHONE
516-435-1110
408-721-2181
310-322-3331
847-843-7500
619-661-6835
270-324-4140
708-956-0666
408-573-4150
847-390-4373
FAX
516-435-1824
408-721-1635
310-322-3332
847-843-2798
619-661-1055
270-490-7222
708-956-0702
408-573-4159
847-390-4428
WEBSITE
www.centralsemi.com
www.fairchildsemi.com
www.irf.com
www.niec.co.jp
www.sumida.com
www.vishay.com
www.sumida.com
www.t-yuden.com
www.component.tdk.com
Note:
Please indicate that you are using the MAX1999 when contacting these component suppliers.
Recommended Equipment
•
•
•
•
7V to 24V power supply, battery, or notebook AC
adapter
Dummy loads capable of sinking 5A
Digital multimeters (DMMs)
100MHz dual-trace oscilloscope
2) Verify that the shunts are across JU1 pins 1 and 2,
JU2 pins 1 and 2, JU3 pins 1 and 4, and JU5 pins 1
and 4.
3) Turn on the power supply.
4) Verify that the output voltages are 3.3V and 5V.
Evaluating Other Output Voltages
Quick Start
1) Ensure that the circuit is connected correctly to the
supplies and dummy load before applying any
power.
The EV kit outputs are preset to 3.3V and 5V. However,
the output voltages can also be adjusted between 2V
and 5.5V by selecting R1/R2 and R3/R4 values. Select
feedback resistors R2 and R4.
R1 and R3 are then given by:
R1 (or R3) = R2 (or R4) x [(V
OUT
/V
FB
) - 1]
where V
FB
= 2V.
2
_______________________________________________________________________________________
MAX1999 Evaluation Kit
Evaluates: MAX1777/MAX1977/MAX1999
VCC
VIN
7V TO 24V
VCC REF
R5
3.9Ω
GND
R12
OPEN
JU8
R13
OPEN
VCC
JU7
R11
OPEN
R14
OPEN
V+
LD05
+5V
C1
10µF
25V
C2
10µF
25V
8
7
N1
3
2
5
6
4
1
BST5
C17
4.7µF
35V
C15
0.1µF
20
8
V+
5
ILIM3
11
ILIM5
18
LDO5
V
CC
17
R17 VCC
47Ω
3
D1
C11
1µF
10V
L
C18
4.7µF
16V
16
14
C9
0.1µF
R8
10Ω
C13*
OPEN
DH5
BST5
C24
1µF
10V
U1
VOUT2
+5V, 5A
L1
7.6µH
15
LX5
MAX1999
(MAX1777)
(MAX1977)
BST3
DH3
LX3
28
26
27
R18
10Ω
2
R
1
BST5
5
6
4
8
7
N3
3
2
C3
10µF
25V
C4
OPEN
C10
0.1µF
C14*
OPEN
1
L2
4.7µH
VOUT1
3.3V, 5A
C8
330µF
6.3V
C7
OPEN
D3
8
7
N2
3
2
1
5
6
4
19
13
DL5
TON
(CS5)
DL3
N.C.
(CS3)
24
1
4
5
6
7
8
D2
C5
OPEN
C6
470µF
4V
R3
OPEN
VCC
R16
SHORT
(PC TRACE)
4
REF
3
2
R10
OPEN
JU6
R7
1MΩ
N4
3
1
2
R15
SHORT
(PC TRACE)
R1
OPEN
JU5
1
5V ON/OFF
4
ON5
OUT3
FB3
22
7
VCC
21
9
OUT5
FB5
R6
100kΩ
VCC
PGOOD
2
12
23
VCC
PGOOD
1
2 JU2
3
R2
SHORT
(PC TRACE)
R4
SHORT
(PC TRACE)
VCC
3.3V ON/OFF
4
REF
3
2
V+
SHDN
1
2
3
JU3
1
3
ON3
SKIP
GND
JU4
JU1
6
10
R9
1MΩ
LD03
3.3V
C16
0.22µF
C12
0.1µF
C19
4.7µF
16V
*OPTIONAL C13 AND C14
REQUIRED FOR ULTRASONIC
MODE OPERATION (MAX1999 ONLY).
SEE TABLE 2.
SHDN
REF
8
LD03
25
PRO
REF
2V
Figure 1. MAX1999 EV Kit Schematic
Evaluating the MAX1777/MAX1977
This EV kit also can be used to evaluate the MAX1777/
MAX1977. The MAX1777 operates at 200kHz/300kHz
switching frequency and the MAX1977 operates at
400kHz/500kHz switching frequency (5V/3.3V). The
MAX1777 and the MAX1977 use accurate current-
sense resistors, R15 and R16:
1) Remove the MAX1999 and install a MAX1777 or
MAX1977.
2) Cut open the traces shorting sense resistors R15
and R16.
3) Install sense resistors R15 and R16.
4) Short resistor R10 (leave JU6 open).
_______________________________________________________________________________________________________
3
MAX1999 Evaluation Kit
Evaluates: MAX1777/MAX1977/MAX1999
Jumper Settings
Table 1. Jumper JU1 Functions (SHDN Mode Selection)
JU1
1 and 2
SHDN
PIN
Connected to V+
MAX1999 OUTPUT
MAX1999 enabled; REF, LDO3, and LDO5 active;
V
OUT1
(3.3V) depends on JU3; V
OUT2
(5.0V) depends on
JU5
Shutdown mode; REF, LDO3, and LDO5 off; V
OUT1
= 0V
and V
OUT2
= 0V
MAX1999 can be driven by an external signal
2 and 3
Not installed
Connected to GND
Connected to
SHDN
pad
Table 2. Jumper JU2 Functions (SKIP Mode Selection)
JU2
1 and 2
2 and 3
SKIP
PIN
Connected to VCC
Connected to GND
OPERATING MODE
Low-noise mode, forced fixed-frequency PWM operation.
Normal operation, allows automatic PWM/PFM switchover for
pulse-skipping at light load, resulting in highest efficiency.
Ultrasonic pulse-skipping mode (20kHz min). Install C13,
C14 (470pF) for MAX1999 ultrasonic mode operation to
ensure proper negative ultrasonic current sensing
(V
NEG(µs)
).
Not installed
Floating
Table 3. Jumper JU3 Functions (Output Voltage V
OUT1
Control)
JU3
1 and 2
1 and 3
1 and 4
ON3 PIN
Connected to GND
Connected to REF (ON5 = VCC)
Connected to VCC
OUTPUT VOLTAGE (V
OUT1
)
V
OUT1
= 0V, disabled
V
OUT1
(3.3V) starts after V
OUT2
(5V) reaches regulation
V
OUT1
= 3.3V, enabled
Table 4. Jumper JU4 Functions (Protection Selection)
JU4
Installed
PRO
PIN
Connected to VCC
Connected to GND through
resistor R9
PROTECTION
Undervoltage and overvoltage fault protection are
disabled.
Undervoltage and overvoltage fault protection are
enabled. Refer to the
Fault Protection
section in the
MAX1999 data sheet for more information.
Not installed
4
_______________________________________________________________________________________
MAX1999 Evaluation Kit
Jumper Settings (continued)
Table 5. Jumper JU5 Functions (Output Voltage V
OUT2
Control)
JU5
1 and 2
1 and 3
1 and 4
ON5 PIN
Connected to GND
Connected to REF (ON3 = VCC)
Connected to VCC
OUTPUT VOLTAGE (V
OUT2
)
V
OUT2
= 0V, disabled
V
OUT2
(5V) starts after V
OUT1
(3.3V) reaches regulation
V
OUT2
= 5V, enabled
Evaluates: MAX1777/MAX1977/MAX1999
Table 6. Jumper JU6 Functions (Switching-Frequency Selection)
JU6
Not installed
Installed
TON PIN
Connected to VCC through
resistor R7
Connected to GND
FREQUENCY (kHz)
200/300 (as shipped)
400/500
Important:
Do not change the operating frequency without first recalculating component values. The switching frequency has a sig-
nificant effect on the peak current-limit level, MOSFET heating, preferred inductor value, PFM/PWM switchover point, output noise,
efficiency, and other critical parameters.
Table 7. Jumper JU7 Functions (Fixed/Adjustable Current-Limit Selection for V
OUT2
)
JU7
SHORT
ILIM5 PIN
Connected to VCC through a PC
board trace.
Connected to REF through
resistor-divider R13/R14. Refer
to the
Current-Limit Circuit
section in the MAX1999 data
sheet for information on
selecting R13/R14.
CURRENT-LIMIT THRESHOLD (mV)
100 (default)
OPEN
Adjustable from 50 to 200
Table 8. Jumper JU8 Functions (Fixed/Adjustable Current-Limit Selection for V
OUT1
)
JU8
SHORT
ILIM3 PIN
Connected to VCC through a PC
board trace.
Connected to REF through
resistor-divider R11/R12.
Refer to the
Current-Limit Circuit
section in the MAX1999 data
sheet for information on
selecting R11/R12.
CURRENT-LIMIT THRESHOLD (mV)
100 (default)
OPEN
Adjustable from 50 to 200
_______________________________________________________________________________________
5
微控制器 MCU
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
