MAX8848Z Evaluation Kit
Evaluates: MAX8847Y/MAX8847Z/
MAX8848Y/MAX8848Z
General Description
The MAX8848Z evaluation kit (EV kit) is a fully assembled
and tested PCB that demonstrates the MAX8848Z high-
performance negative charge pump. The MAX8848Z
integrates an inverting charge pump and 7 current regu-
lators capable of 24mA each to drive up to 7 white LEDs
(WLEDs). The EV kit operates from a 2.7V to 5.5V input
supply range and includes two pulse generators that
are used for testing the MAX8847Y/MAX8848Y single-
wire, serial-pulse dimming feature. The EV kit can also
evaluate the MAX8847Y, MAX8847Z, and MAX8848Y.
To evaluate the MAX8847Y, MAX8847Z, or MAX8848Y,
request a free sample when ordering the EV kit.
S
Negative 1x/1.5x Charge Pump
S
Adaptive Current Regulators
S
Independent Voltage Supply for Each LED
S
24mA to 0.1mA Serial-Pulse Dimming (MAX8847Y/
Features
MAX8848Y)
S
24mA to 0mA PWM Dimming (MAX8847Z/
MAX8848Z)
S
2% (max) LED Current Accuracy, 1% (typ)
Matching
S
Low 120µA Quiescent Current
S
Low 0.4µA Shutdown Current
S
Inrush Current Limit
S
Temperature Derating Function
S
16-Pin, 3mm x 3mm Thin QFN Package
S
Tiny External Components
S
Fully Assembled and Tested
Ordering Information
PART
MAX8848ZEVKIT+
TYPE
EV Kit
+Denotes
lead(Pb)-free and RoHS compliant.
Component List
DESIGNATION
C1–C4
QTY
4
DESCRIPTION
1FF
Q20%,
10V X5R ceramic
capacitors (0603)
TDK C1608X5R1A105K
0.22FF
Q10%,
10V X5R ceramic
capacitor (0402)
Murata GRM155R61A224KE19
2.2FF
Q10%,
6.3V X5R ceramic
capacitors (0603)
TDK C1608X5R0J225K
1000pF
Q10%,
50V X7R ceramic
capacitors (0402)
TDK C1005X7R1H102K
White LEDs
Nichia NSCW215T
OSRAM LW Y1SG
DESIGNATION
D8, D9
QTY
2
DESCRIPTION
100mA, 30V Schottky diodes
(SOD523)
Central Semi CMOSH-3
2-pin headers, 0.1in centers
Sullins PEC36SAAN
Digi-Key S1012E-36-ND
3-pin headers, 0.1in centers
Sullins PEC36SAAN
Digi-Key S1012E-36-ND
2.2kI
Q5%
resistors (0402)
Momentary pushbutton switches
Panasonic EVQ-PHP03T
Digi-Key P8002STR-ND
Negative charge pump
(16 TQFN-EP*)
Maxim MAX8848ZETE+
C5
1
JU1, JU2, JU4,
JU5
JU3, JU6, JU7,
JU8
R1, R2
S1, S2
4
C6, C8
2
4
2
2
C7, C9
2
D1–D7
7
U1
*EP = Exposed pad.
1
For pricing, delivery, and ordering information, please contact Maxim Direct
at 1-888-629-4642, or visit Maxim’s website at www.maximintegrated.com.
19-5604; Rev 0; 11/10
MAX8848Z Evaluation Kit
Evaluates: MAX8847Y/MAX8847Z/
MAX8848Y/MAX8848Z
Component List (continued)
DESIGNATION
QTY
DESCRIPTION
Single-switch debouncer
(4 SOT143)
Maxim MAX6816EUS+T
(Top Mark: KABA)
DESIGNATION
—
QTY
8
DESCRIPTION
Shunts (JU1–JU8)
Sullins STC02SYAN
Digi-Key S9000-ND or equivalent
PCB: MAX8848Z EVALUATION
KIT+
U2, U3
2
—
1
Component Suppliers
SUPPLIER
Central Semiconductor Corp.
Digi-Key Corp.
Murata Electronics North America, Inc.
Nichia Corp.
OSRAM Opto Semiconductor
Sullins Electronics Corp.
TDK Corp.
PHONE
631-435-1110
800-344-4539
770-436-1300
248-352-6575
888-446-7726
760-744-0125
847-803-6100
www.digikey.com
www.murata-northamerica.com
www.nichia.com
www.osram-os.com
www.sullinselectronics.com
www.component.tdk.com
WEBSITE
www.centralsemi.com
Note:
Indicate that you are using the MAX8848Z when contacting these component suppliers.
Quick Start
•
•
MAX8848Z EV kit
Detailed Description
The MAX8848Z EV kit default jumper settings are shown
in Table 1.
Recommended Equipment
Variable 6V power supply or a Li+ battery capable
of supplying 1A of output current
The EV kit is a fully assembled and tested surface-mount
board. Follow the steps below to verify board operation.
Caution: Do not turn on the power supply until all
connections are made.
1)
2)
3)
Verify that the jumpers on the EV kit are configured
in their default positions, as shown in Table 1.
Preset the power supply to 3.6V. Turn off the power
supply.
Connect the positive lead of the 3.6V power supply
to the IN pad. Connect the negative lead of the 3.6V
power supply to the GND pad.
Turn on the power supply.
Verify that all the WLEDs (D1–D7) are lit.
Procedure
To evaluate the MAX8847Y, MAX8847Z, and MAX8848Y,
carefully remove the MAX8848Z (U1) and install the
MAX8847Y, MAX8847Z, or MAX8848Y. Capacitor C5
needs to be removed for the MAX8848Y evaluation.
All other components can remain the same. Jumper
settings need to be adjusted for different operations on
different ICs.
Evaluating the
MAX8847Y/MAX8847Z/MAX8848Y
4)
5)
Apply an external PWM signal to ENA to set the
corresponding LED current that is proportional to the
signal duty cycle (0% duty cycle corresponds to zero
LED current and 100% duty cycle corresponds to full
LED current). The allowed PWM frequency range is
between 200Hz and 200kHz. If PWM dimming control is
not required, ENA works as a simple on/off control.
PWM Dimming Control
(MAX8847Y/MAX8847Z/MAX8848Z)
2
Maxim Integrated
MAX8848Z Evaluation Kit
Evaluates: MAX8847Y/MAX8847Z/
MAX8848Y/MAX8848Z
On-board pulse generators are provided to evaluate
the serial-pulse dimming feature of the MAX8847Y/
MAX8848Y. When first enabled, the LEDs are at full
brightness. Repeatedly pressing the S1 or S2 switch
generates pulses to reduce the LED current from 24mA
to 0.1mA in 31 steps, as shown in Table 2. After the
current reaches 0.1mA, the next button press restores
the LED current to 24mA. Refer to the MAX8847Y/
MAX8847Z and MAX8848Y/MAX8848Z IC data sheets
for timing diagrams.
To use the ENA on-board pulse generator, remove the
JU3 shunt and install shunts on JU1 and JU2. To use the
ENB on-board pulse generator, remove the JU6 shunt
and install shunts on JU5 and JU4, or across pins 1-2
of JU7.
To use external pulse generators, remove the shunts
on jumper JU1, JU4, or JU7 to disconnect the on-board
pulse generators. Connect the external pulse generator
to the ENA and ENB pads-
Serial Pulse-Dimming Control
(MAX8847Y/MAX8848Y)
Table 2. ENA/ENB Serial-Pulse-Dimming
Count and Programmed LED_ Currents
ENA/ENB
PULSE
COUNT
Startup
or EN_
high
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
PROGRAMMED
LED CURRENT
(mA)
24.0
22.4
20.8
19.2
17.6
16.0
14.4
12.8
11.2
9.6
8.0
6.4
5.6
4.8
4.0
3.2
ENA/ENB PROGRAMMED
PULSE
LED CURRENT
COUNT
(mA)
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
2.8
2.4
2.0
1.6
1.4
1.2
1.0
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
24.0
Table 1. Default Jumper Settings
JUMPER
JU1
JU2
JU3
JU4
JU5
JU6
JU7
JU8
SHUNT POSITION
Open
Open
Pins 1-2
Open
Open
Open
Pins 2-3
Open
Maxim Integrated
3
MAX8848Z Evaluation Kit
Evaluates: MAX8847Y/MAX8847Z/
MAX8848Y/MAX8848Z
C2
1µF
IN
VIN
1
C1
1µF
2
3
C1P
IN
TP1
GND
LED1
8
TP2
ENA
16
LED2
ENA
LED3
10
9
D2
TP3
D3
TP4
LED4
NEG
11
TP5
7
NEG
EP
LED6
CPWM (ENB)
15
C5
0.22µF
13
LED5
12
D5
TP6
D6
D4
U1
D1
6
C1N
4
C2P
C3
1µF
5
C2N
IN
JU3
IN
1
2
3
GND
JU2
C6
2.2µF
V
CC
R1
2.2kI
D8
JU1
IN
S1
U2
MAX6816
MAX8848Z
OUT
C7
1000pF
IN
JU6
1
2
3
C4
1µF
GND
IN
CPWM
JU5
C8
2.2µF
V
CC
R2
2.2kI
D9
JU4
TP7
LED7
14
D7
IN
S2
U3
MAX6816
1
OUT
C9
1000pF
NOTE:
REMOVE C5 FOR MAX8848Y EVALUATION.
< > FOR MAX8847Y/MAX8847Z, ( ) FOR MAX8848Y
2 3
JU7
JU8
IN
1
2
3
LED7 <ENB>
GND
Figure 1. MAX8848Z EV Kit Schematic
4
Maxim Integrated
MAX8848Z Evaluation Kit
Evaluates: MAX8847Y/MAX8847Z/
MAX8848Y/MAX8848Z
1933Mils
1933Mils
1888Mils
1888Mils
Figure 2. MAX8848Z EV Kit Component Placement Guide—
Top Layer
Figure 3. MAX8848Z EV Kit PCB Layout—Top Layer
1933Mils
1888Mils
Figure 4. MAX8848Z EV Kit PCB Layout—Bottom Layer
Maxim Integrated
5
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