General Description
The MAX17094 evaluation kit (EV kit) is a fully assem-
bled and tested surface-mount PCB that provides the
voltages and features required for active-matrix, thin-
film transistor (TFT), liquid-crystal displays (LCDs). The
EV kit contains a high-performance step-up switching
regulator, a 250mA low-dropout (LDO) linear regulator,
a high-speed op amp, a digitally adjustable VCOM cali-
brator, and seven high-voltage level-shifting buffers for
scan-driver applications.
The EV kit operates from a DC supply voltage from
+1.8V to +5.5V. The step-up switching regulator is con-
figured for a +8V output providing at least 300mA from
a +2.5V input. The positive charge pump is configured
for a +21.5V output providing up to 30mA. The negative
charge pump is configured for a -6.5V output providing
up to 30mA. The op amp is capable of providing up to
±150mA peak and features a programmable output
voltage initially configured for +3.2V. The low-voltage,
low-dropout linear regulator can provide at least
250mA. The high-voltage, level-shifting scan driver
buffers seven logic inputs and shifts them to a desired
level to drive TFT LCD row logic.
The MAX17094 EV kit demonstrates low quiescent cur-
rent and high efficiency (> 85%) for maximum battery
life. Operation at 1.2MHz allows the use of tiny surface-
mount components. The MAX17094 thin QFN package
(0.8mm max height), with low-profile external compo-
nents, allows this circuit to be less than 2mm high.
The MAX17094 EV kit provides an on-board I2C/
SMBus™ interface and connects to the computer through
the universal serial bus (USB) port. The EV kit includes
Windows®2000/XP®and Windows Vista®-compatible
software that provides a graphical user interface (GUI) for
control of the MAX17094’s programmable features.
Features
o+1.8V to +5.5V Input Range
oAdjustable 450kHz to 1.2MHz Step-Up Switching
Frequency
oOutput Voltages
+8V Output at 300mA (Step-Up Switching
Regulator)
+21.5V Output at 30mA (Positive Charge Pump)
-6.5V Output at 30mA (Negative Charge Pump)
+2.5V at 250mA (Linear Regulator)
±150mA High-Current Op-Amp Output
oResistor-Adjustable Switching Regulator and Op-
Amp Output Range
oDigitally Programmable Op-Amp Output Voltage
o+30V to -10V High-Voltage Level-Shifting Drivers
o> 85% Efficiency (Step-Up Switching Regulator)
oOn-Board I2C/SMBus Interface Control through
USB
oWindows 2000/XP- and Windows Vista (32-Bit)-
Compatible Software
o2mm Low-Profile Surface-Mount Components
oLead(Pb)-Free and RoHS Compliant
oFully Assembled and Tested
Evaluates: MAX17094
MAX17094 Evaluation Kit
________________________________________________________________
Maxim Integrated Products
1
19-4451; Rev 0; 2/09
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
SMBus is a trademark of Intel Corp.
Windows, Windows XP, and Windows Vista are registered
trademarks of Microsoft Corp.
Ordering Information
PART TYPE
MAX17094EVKIT+ EV Kit
+
Denotes lead(Pb)-free and RoHS compliant.
Component List
DESIGNATION
QTY
DESCRIPTION
C1 1
4.7µF ±10%, 6.3V X5R ceramic
capacitor (0603)
Murata GRM188R60J475K
TDK C1608X5R0J475K
C2, C3 2
1µF ±20%, 6.3V X5R ceramic
capacitors (0402)
Murata GRM155R60J105K
TDK C1005X5R0J105M
C5 1
10µF ±20%, 6.3V X5R ceramic
capacitor (0603)
Murata GRM188R60J106M
TDK C1608X5R0J106K
DESIGNATION
QTY
DESCRIPTION
C6–C9, C14,
C16–C19, C34
10
0.1µF ±10%, 50V X7R ceramic
capacitors (0603)
Murata GRM188R71H104K
TDK C1608X7R1H104K
C10 0 Not installed, ceramic capacitor
(0805)
C11, C12 2
4.7µF ±10%, 16V X5R ceramic
capacitors (0805)
Murata GRM21BR61C475K
Taiyo Yuden EMK212BJ475KG
Evaluates: MAX17094
MAX17094 Evaluation Kit
2 _______________________________________________________________________________________
Component List (continued)
DESIGNATION QTY DESCRIPTION
C13 1
1000pF ±10%, 50V X7R ceramic
capacitor (0402)
Murata GRM155R71H102K
TDK C1005X7R1H102K
C15 1
0.47μF ±10%, 25V X5R ceramic
capacitor (0603)
Murata GRM188R71E474K
TDK C1608X5R1E474K
C20–C27 8
100pF ±5%, 50V C0G ceramic
capacitors (0402)
Murata GRM1555C1H101J
TDK C1005C0G1H101J
C28, C29, C31,
C58–C65 0Not installed, ceramic capacitors
(0402)
C30 0
Not installed, through-hole
OS-CON capacitor
(OSCON-B)
C32 0
Not installed, ceramic capacitor
(0603)
C33 1
15pF ±5%, 50V C0G ceramic
capacitor (0402)
Murata GRM1555C1H150J
TDK C1005C0G1H150J
C35 1
0.22μF ±10%, 16V X7R ceramic
capacitor (0603)
Murata GRM188R71C224K
TDK C1608X7R1C224K
C36–C39, C42,
C44 6
1μF ±10%, 16V X7R ceramic
capacitors (0603)
Murata GRM188R71C105K
TDK C1608X5R1C105K
C40, C43, C45 3
10μF ±10%, 16V X5R ceramic
capacitors (0805)
KEMET C0805C106K4PACTU
C41, C48–C53,
C57 8
0.1μF ±10%, 16V X7R ceramic
capacitors (0603)
TDK C1608X7R1C104K
Murata GRM188R71C104K
C46, C47 2
22pF ±5%, 50V C0G ceramic
capacitors (0603)
Murata GRM1885C1H220J or
TDK C1608C0G1H220J
C54, C55 2
10pF ±5%, 50V C0G ceramic
capacitors (0603)
Murata GRM1885C1H100J
TDK C1608C0G1H100J
DESIGNATION
QTY
DESCRIPTION
C56 1
0.033µF ±10%, 16V X5R ceramic
capacitor (0603)
Taiyo Yuden EMK107BJ333KA
C66–C73 8
3900pF ±10%, 50V X7R ceramic
capacitors (0402)
Murata GMD155R71H392K
D1, D2, D3 3
30V , 200m A d ual d i od es ( 3 S OT23)
Zetex BAT54S
Fairchild BAT54S
D4 1 30V, 1A Schottky diode (S-Flat)
Toshiba CRS02
H1 0 Not installed, 2 x 5-pin JTAG
header
JU1, JU3–JU11,
JU14–JU21 18 3-pin headers
JU2 1 2-pin header
JU12, JU13 0 Not installed, 2-pin headers
L1 1
4.1µH, 1.95A, 57MΩ inductor (6mm
x 6mm x 2mm)
Sumida CDRH5D18NP-4R1NC
Coiltronics SD6020-4R1-R
L2 1
Ferrite bead (0603)
TDK MMZ1608R301A
Murata BLM18SG700 TN1
P1 1 USB type-B right-angle PC-mount
receptacle
R1 1 63.4kΩ ±1% resistor (0402)
R2, R16, R17
3 200kΩ ±1% resistors (0402)
R3 1 36.5kΩ ±1% resistor (0402)
R4 1 40.2kΩ ±1% resistor (0402)
R5 1 6.81kΩ ±1% resistor (0402)
R6 1 15kΩ ±1% resistor (0402)
R7, R9–R15,
R28, R29 10 100kΩ ±5% resistors (0402)
R8, R32, R33,
R34 0 Not installed, resistors (0603)
R18 1 21kΩ ±1% resistor (0402)
R19, R20 2 0Ω resistors (0402)
R21 1 24.9kΩ ±1% resistor (0402)
R22, R23, R26,
R27, R48–R59
16 604Ω ±1% resistors (1206)
R24 1 80.6kΩ ±1% resistor (0402)
Evaluates: MAX17094
MAX17094 Evaluation Kit
_______________________________________________________________________________________ 3
Component List (continued)
Component Suppliers
DESIGNATION
QTY
DESCRIPTION
R25 0 Not installed, resistor—shorted by
PCB trace (0603)
R30, R31 2 10kΩ ±5% resistors (0402)
R35 1 169kΩ ±1% resistor (0603)
R36 1 100kΩ ±1% resistor (0603)
R37, R38 2 27Ω ±5% resistors (0603)
R39 1 1.5kΩ ±5% resistor (0603)
R40 1 2.2kΩ ±5% resistor (0603)
R41 1 470Ω ±5% resistor (0603)
R42 1 10kΩ ±5% resistor (0603)
R43–R47 0 Not installed, resistors—shorted by
PCB trace (0402)
SW1 1 7-position low-profile surface-mount
DIP switch
SW2 1 2-position low-profile surface-mount
DIP switch
U1 1
Internal switch boost regulator
(48 TQFN-EP*)
Maxim MAX17094ETM+
DESIGNATION
QTY
DESCRIPTION
U2 1 Microcontroller (68 QFN-EP*)
Maxim MAXQ2000-RAX+
U3 1 2.5V LDO regulator (5 SO70)
Maxim MAX8511EXK25+
U4 1
Adjustable output LDO regulator
(5 SO70)
Maxim MAX8512EXK+
U5 1 U ART- to- U S B conver ter ( 32 TQFP )
FTD I FT232BL
U6 1
93C46 typ e ( 64k x 16) 3- w i re E EP ROM
(8 SO)
Atmel AT93C46EN-SH-B
U7, U8 2 Log i c- l evel tr ansl ator s ( 10 µM AX
®
)
M axi m M AX 1840E U B+
Y1 1 16MHz crystal
Y2 1 6MHz crystal
— 19 Shunts
—1
P C B: M AX 17094 E V ALU ATIO N KIT+
*
EP = Exposed pad.
Note: Indicate that you are using the MAX17094 when contacting these component suppliers.
µMAX is a registered trademark of Maxim Integrated Products, Inc.
SUPPLIER PHONE WEBSITE
Cooper Bussmann 916-941-1117 www.cooperet.com
Fairchild Semiconductor 888-522-5372 www.fairchildsemi.com
KEMET Corp. 864-963-6300 www.kemet.com
Murata Electronics North America, Inc. 770-436-1300 www.murata-northamerica.com
Sumida Corp. 847-545-6700 www.sumida.com
Taiyo Yuden 800-348-2496 www.t-yuden.com
TDK Corp. 847-803-6100 www.component.tdk.com
Toshiba America Electronic Components, Inc.
949-623-2900 www.toshiba.com/taec
Zetex Semiconductors 631-543-7100 www.zetex.com
MAX17094 EV Kit Files
FILE DESCRIPTION
INSTALL.EXE Installs the EV kit files on your computer
MAX17094.EXE Application program
FTD2XX.INF USB device driver file
UNINST.INI Uninstalls the EV kit software
TROUBLESHOOTING_USB.PDF USB driver installation help file
Evaluates: MAX17094
Quick Start
Recommended Equipment
• 1.8V to 5.5V, 2A DC power supply
• User-supplied Windows 2000/XP or Windows Vista
PC with a spare USB port
• Voltmeter
Note: In the following sections, software-related items
are identified by bolding. Text in bold refers to items
directly from the EV kit software. Text in bold and
underlined refers to items from the Windows operating
system.
Procedure
The MAX17094 EV kit is fully assembled and tested.
Follow the steps below to verify board operation.
Caution: Do not turn on the power supply until all
connections are completed.
1) Verify that a shunt is installed across jumper JU2.
2) Set an external power supply to ≈+3.3V. Connect
the positive terminal of the power supply to the VIN
pad. Connect the negative terminal of the power
supply to the PGND pads closest to VIN.
3) Turn on the power supply and verify that the step-
up switching regulator output (MAIN) is +8V.
4) Verify that the positive charge-pump supply (VP) is
approximately +24V.
5) Verify that the negative charge-pump supply (VN) is
approximately -8.8V.
6) Verify that the linear regulator output (VLOGIC) is
approximately 2.5V.
7) Visit www.maxim-ic.com/evkitsoftware to down-
load the latest version of the MAX17094 EV kit soft-
ware, MAX17094Rxx.ZIP. Save the EV kit software
to a temporary folder and uncompress the ZIP file.
8) Install the EV kit software on your computer by run-
ning the INSTALL.EXE program inside the tempo-
rary folder. The program files are copied and icons
are created in the Windows Start | Programs menu.
9) Connect the USB cable from the PC to the EV kit
board. A Building Driver Database window pops
up in addition to a New Hardware Found message
when installing the USB driver for the first time. If
you do not see a window that is similar to the one
described above after 30 seconds, remove the
USB cable from the board and reconnect it.
Administrator privileges are required to install the
USB device driver on Windows 2000/XP/Vista.
10) Follow the directions of the Add New Hardware
Wizard to install the USB device driver. Choose the
Search for the best driver for your device option.
Specify the location of the device driver to be
C:\Program Files\MAX17094 (default installation
directory) using the Browse button. During device
driver installation, Windows may show a warning
message indicating that the device driver Maxim
uses does not contain a digital signature. This is not
an error condition and it is safe to proceed with instal-
lation. Refer to the TROUBLESHOOTING_USB.PDF
document included with the software for additional
information.
11) Start the MAX17094 EV kit software by opening its
icon in the Start | Programs menu.
12) Normal device operation is verified when
MAX17094 device connected appears in the
status bar on the MAX17094 EV kit main window
(Figure 1).
13) Verify that the output of the high-speed op amp
(VCOM) is approximately +3.2V.
MAX17094 Evaluation Kit
4 _______________________________________________________________________________________
Figure 1. MAX17094 EV Kit Software Main Window
Detailed Description of Hardware
The MAX17094 EV kit contains a high-performance
step-up switching regulator, a 250mA LDO, a positive
two-stage charge pump, a negative single-stage
charge pump, a high-speed op amp, and seven high-
voltage level-shifting buffers for scan-driver applica-
tions. The EV kit operates from a DC power supply
between +1.8V and +5.5V that provides at least 2A.
As configured, the step-up switching regulator (VMAIN)
generates a +8V output and provides at least 300mA.
The step-up switching-regulator output voltage can be
adjusted up to +14V with different feedback resistors
(see the
Output-Voltage Selection
section).
The GON consists of two positive charge-pump stages
to generate approximately +21.5V and provides
up to 30mA. The GOFF consists of a single negative
charge-pump stage to generate approximately -6.5V
and provides up to 30mA. Loading GON and GOFF
reduces the available VMAIN current proportionally.
The op-amp output (VCOM) is SMBus programmable
and is configured for a +2.4V to +4V output-voltage
range. VCOM can source or sink peak current up to
150mA. The output-voltage range can be reconfigured
to other voltages with voltage-divider resistors R16 and
R17. Refer to the
Setting the VCOM Adjustment Range
section in the MAX17094 IC data sheet for more details.
The seven logic-level to high-voltage level-shifting
buffers can buffer seven logic inputs (A2–A8) and shift
them to a desired level (Y2–Y8) to drive TFT LCD row
logic. Each buffer outputs the voltage on the GOFF pin
(set through JU1) when its respective input is logic-low.
Each buffer (Y2–Y6) outputs the voltage-on GON1 (set
through JU3) when its respective input is logic-high.
Similarly, Y7 and Y8 output the voltage on GON2 (set
through JU4).
The seven switches within SW1 are used to select logic
levels on A2–A8 for testing purposes. Set each switch
open when driving A2–A8 with external logic. Use
jumpers JU14–JU18 to select between capacitive loads
on outputs Y2–Y8 and YDCHG for testing purposes.
GOFF Power Supply (JU1)
The MAX17094 EV kit incorporates jumper JU1 to pro-
vide an option to supply the gate-off (GOFF) supply.
GOFF can be supplied either through the on-board
negative charge pump (VN) or with an externally
applied voltage at the GOFF pad. See Table 1 for
jumper JU1 configuration.
Enable (JU2)
The MAX17094 EV kit incorporates jumper JU2 to
enable/disable the IC outputs. When EN is pulled low,
the DC-DC converter and op amp are disabled. The
high-voltage drivers and LDO will remain active if suffi-
cient voltage is available for operation. See Table 2 for
jumper JU2 configuration.
GON1, GON2 Power Supply (JU3, JU4)
The MAX17094 EV kit incorporates jumpers JU3 and
JU4 to provide an option to supply the gate-on (GON1,
GON2) supplies. GON1 and GON2 can be supplied
either through the on-board positive charge pump (VP)
or with an externally applied voltage at the respective
GON_ pad. See Table 3 for jumpers JU3 and JU4 con-
figuration.
Evaluates: MAX17094
MAX17094 Evaluation Kit
_______________________________________________________________________________________ 5
Table 1. Jumper JU1 Functions
SHUNT
POSITION GOFF PIN
1-2* Supplied on board through negative charge
pump (VN)
2-3 E xter nal user - sup p l i ed vol tag e ap p l i ed at GOFF p ad
*
Default position.
Table 2. Jumper JU2 Functions
SHUNT
POSITION EN PIN EV KIT OUTPUTS
Installed* Connected to VIN Outputs enabled
(MAIN = +8V)
Not installed Pulled to AGND
through R7
Outputs disabled
(MAIN ≈ VIN)
*
Default position.
Table 3. Jumper JU3, JU4 Functions
SHUNT
POSITION GON_ PIN
1-2* Supplied on board through positive charge
pump (VP)
2-3 External user-supplied voltage applied at GON_
pad
*
Default position.
Evaluates: MAX17094
Level-Shifter Logic-Level Inputs
(JU5–JU11)
The MAX17094 level-shifter inputs can be supplied
either using the on-board logic or from an externally
applied signal through configuration of jumpers
JU5–JU11. Additionally, when using on-board logic,
SW1 controls the logic levels based on its own settings.
When SW1 is on, the logic input is high. When SW1 is
off, the logic input is pulled low through a 100kΩpull-
down resistor. See Table 4 for jumpers JU5–JU11 con-
figuration.
Level-Shifter Output Loading (JU14–JU21)
The MAX17094 EV kit incorporates jumpers JU14–JU21
to provide loading options at the level-shifter outputs,
YDCHG and Y2–Y8. See Table 5 for jumpers JU14–JU21
configuration.
Output-Voltage Selection
The MAX17094 EV kit’s step-up switching-regulator out-
put (VMAIN) is set to +8V by feedback resistors R2 and
R3. To generate output voltages other than +8V (up to
+14V), select different external voltage-divider resis-
tors, R2 and R3. Note that changing the VMAIN voltage
setting changes the VN and VP charge-pump output
voltages. Refer to the
Main Step-Up Regulator
and
Output-Voltage Selection
sections in the MAX17094 IC
data sheet for more information.
Detailed Description of Software
The MAX17094 device includes a calibrator used for
adjusting an LCD’s backplane voltage (VCOM) in TFT
LCD displays. The VCOM voltage is adjusted by con-
trolling the amount of sink current from a current source
connected to the POS terminal of the op amp. This is
accomplished by programming the desired setting into
the device’s 7-bit internal DAC. The MAX17094 sup-
ports four different I2C slave addresses; configure SW2
to select between different addresses. Refer to the
MAX17094 IC data sheet for further details.
Loading 7-Bit DAC Setting
The DAC setting corresponds to a certain sink-current
level, which in turn corresponds to a specific VCOM
voltage. With the MAX17094 EV kit software, the
device’s 7-bit internal DAC is configured by entering an
appropriate DAC setting into the Load DAC edit box.
The DAC setting can be set from 0x00 (VCOMMIM) to
0x7F (VCOMMAX). The DAC setting is written to the
device by pressing the Load DAC button (Figure 1).
Reading 7-Bit DAC
The MAX17094 7-bit DAC is read by either pressing the
Read DAC button or by checking the DAC polling
checkbox. When checked, the software continuously
reads and displays the DAC’s current setting.
Access Control Register
The Write To group box is used to select whether
volatile (WR) or nonvolatile (IVR) memory is accessed
during read and write cycles involving the data register.
When the WR/IVR radio button is selected, data on the
data register is written to both the WR and IVR. When
the WR Only radio button is selected, data on the data
register is written to the WR only.
Simple SMBus Commands
There are two methods for communicating with the
MAX17094: through the MAX17094 EV kit software
main window (Figure 1), or through the interface win-
dow available by selecting the Action | Interface
Diagnostic Window menu item from the menu bar. The
Maxim command module interface window (Figure 2)
includes a 2-wire interface tab that allows for execu-
tion of the SMBusSendByte(), SMBusReceiveByte(),
and SMBusQuick() commands. See Table 6 for details
regarding SMBus commands.
The Command byte and Data Out combo boxes
accept numeric data in binary, decimal, or hexadeci-
mal. Hexadecimal numbers should be prefixed by $ or
0x. Binary numbers must be exactly eight digits. See
Figure 2 for an illustration of this tool.
MAX17094 Evaluation Kit
6 _______________________________________________________________________________________
Table 4. Jumper JU5–JU11 Functions
SHUNT
POSITION A2–A8 INPUT PINS
1-2 Supplied through external signal applied at
A2–A8 pad
2-3* Supplied on board based on SW1 states
*
Default position.
Table 5. Jumper JU14–JU21 Functions
SHUNT
POSITION YDCHG, Y2–Y8 PINS
1-2* Minimum loading
2-3 Maximum loading
*
Default position.
Evaluates: MAX17094
MAX17094 Evaluation Kit
_______________________________________________________________________________________ 7
Figure 2. Command Module Interface Window
Table 6. SMBus Commands
CONTROL SMBus
COMMAND FORMAT
Load DAC SMBusWriteByte Input the desired 7-bit DAC setting into the Data Out combo box. The 7-bit DAC value should
be stored in the lower 7 bits (b6–b0) of the byte; the MSB is ignored.
Read DAC SMBusReadByte Receives 8 bits from the device. The lower 7 bits correspond to the current DAC setting and
the MSB is ignored.
Device
search SMBusQuick Search for device address shown in the Target Device Address combo box. The MAX17094
device address can be 50, 52, 54, or 56.
Evaluates: MAX17094
MAX17094 Evaluation Kit
8 _______________________________________________________________________________________
Figure 3a. MAX17094 EV Kit Schematic (Sheet 1 of 3)
Evaluates: MAX17094
MAX17094 Evaluation Kit
_______________________________________________________________________________________ 9
Figure 3b. MAX17094 EV Kit Schematic (Sheet 2 of 3)
Evaluates: MAX17094
MAX17094 Evaluation Kit
10 ______________________________________________________________________________________
Figure 3c. MAX17094 EV Kit Schematic (Sheet 3 of 3)
Evaluates: MAX17094
MAX17094 Evaluation Kit
______________________________________________________________________________________ 11
Figure 4. MAX17094 EV Kit Component Placement Guide—Component Side
Evaluates: MAX17094
MAX17094 Evaluation Kit
12 ______________________________________________________________________________________
Figure 5. MAX17094 EV Kit PCB Layout—Component Side
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________
13
© 2009 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc.
Evaluates: MAX17094
MAX17094 Evaluation Kit
Figure 6. MAX17094 EV Kit PCB Layout—Solder Side
