Renesas ISL9238EVAL1Z User manual

USER’S MANUAL
UG074
Rev.2.00
Nov 14, 2018
ISL9238EVAL1Z
Evaluation Board User Guide
UG074 Rev.2.00 Page 1 of 17
Nov 14, 2018
Description
The ISL9238is a buck-boost Narrow Output Voltage DC (NVDC)
charger that uses the Renesas advanced R3™ Technology to
provide high light-load efficiency, fast transient response, and
seamless DCM/CCM transitions for a variety of mobile and
industrial applications.
In Charge mode, the ISL9238 takes input power from a wide
range (4V to 20V) of DC power sources (conventional AC/DC
charger adapters, USB PD ports, travel adapters, etc.) and
safely charges battery packs with up to four cells in a series
configuration.
The ISL9238 has an On-the-Go (OTG) function for 2- and 4-cell
battery applications. When the OTG function is enabled, the
ISL9238 operates in Reverse Buck mode to provide 5V at the
USB port.
The ISL9238 provides serial communication with SMBus/I2C
that allows programming of critical parameters to deliver a
customized solution. The programmable parameters include,
but are not limited to: adapter current limit, charger current
limit, system voltage setting, and trickle charging current limit.
The ISL9238EVAL1Z evaluation board demonstrates the
performance of the ISL9238. The default value numbers of the
battery in series, switching frequency, and the adapter current
limit charging function can be programmed by the resistor
from the PROG pin to GND. The values also can be set by
SMBus.
Related Literature
For a full list of related documents, refer to our website:
•ISL9238datasheet
Key Features
• Buck-boost NVDC charger for 1-, 2-, 3-, 4-cell Li-ion batteries
• End of Charge (EOC) option
• System power monitor PSYS output, IMVP-8 compliant
• PROCHOT# open-drain output, IMVP-8 compliant
• Allows trickle charging of depleted battery
• Optional ASGATE FET control
• Ideal diode control in Turbo mode
• Reverse buck, boost, and buck-boost operation from battery
• Two-level adapter current limit available
• Battery Ship mode option
• SMBus and auto-increment I2C compatible
Specifications
•V
IN = 3.8V to 24V (no dead zone)
•V
OUT = 2.5V to 12.6V
•MAXI
charge up to 6A
•f
SW = 1MHz maximum
Ordering Information
PART NUMBER DESCRIPTION
ISL9238EVAL1Z ISL9238 buck-boost charger evaluation board
FIGURE 1. BLOCK DIAGRAM
ISL9238
BOOT1
PHASE1
UGATE1
VDDP
LGATE1 LGATE2
UGATE2
PHASE2
BOOT2
SCL
SDA
VBAT
CSOP
CSON
DCIN
VDD
COMP
PSYS
BGATE
ASGATE
PROCHOT#
ACIN
ACOK
GND
CSIP
CSIN
AMON/BMON
BATGONE
VADP
VBAT
VSYS
PROG
VSYS
OTGPG/CMOUT
ADP
OTGEN/CMIN
Q1
Q2
Q4
Q3
Rs1
Rs2
L1
Optio nal

UG074 Rev.2.00 Page 2 of 17
Nov 14, 2018
ISL9238EVAL1Z
Recommended Equipment
• 0V to 25V power supply with at least 6A source current capability
• Electronic load capable of sinking current up to 6A
• Battery emulator capable of sinking and sourcing current up to
6A
• Digital Multimeters (DMMs)
• 100MHz quad-trace oscilloscope
NOTE: You can use a power supply (that can source current but cannot
sink current) in parallel with an e-load Constant Current (CC) mode to
emulate the battery. For example, to charge, set the charging current
command lower than the CC mode e-load. If the e-load CC mode current
is set to 3A, the charge current command is 2A, and the e-load takes 2A
from the charger and takes another 1A from the power supply in parallel
with it. To discharge, the power supply acts like the battery to discharge
current. You can also use the e-load Constant Voltage (CV) mode to
emulate the battery to take the charging current from the charger and set
the e-load CV voltage below the MaxSysV register setting; however, this
e-load CV mode cannot source current like a battery.
Functional Description
The ISL9238EVAL1Z provides all circuits required to evaluate the
features of the ISL9238. A majority of the features of the
ISL9238, such as adjustable output voltage, On-the-Go (OTG)
mode, Trickle Charging mode for depleted battery, and system
power monitor at Buck, Boost, and Buck-Boost modes are
available on this evaluation board.
Quick Start Guide
The number of battery cell and adapter current limit default
values can be configured with a standard 1% 0603 resistor (R23)
from the PROG pin to GND. The “PROG PIN PROGRAMMING
OPTIONS” table in the ISL9238 datasheet shows the
programming options. After the default number of cells in series
is set, the default values for MaxSystemVoltage and
MinSystemVoltage are set accordingly. These values can also be
changed through the SMBus control registers in the Renesas GUI,
shown in Figure 2 on page 3.
The three LEDs indicate the ACOK, PROCHOT, and
OTGPG/CMOUT status, respectively. For more details about the
functions of these three pins, refer to the ISL9238 datasheet.
Complete the following steps to evaluate the ISL9238 key
functions,including system voltage regulation, input current limit
regulation, Charging mode, trickle Charging mode, and OTG
mode. Figure 3 shows the top view of the evaluation board and
highlights the key testing points and connection terminals. For
more information about the ISL9238, including other modes of
operation, refer to the ISL9238 datasheet.
System Voltage Regulation
1. Set the power supply to 5V. Disable the output and connect
the (+) end to J1 and the (-) end to J2.
2. Ensure jumpers JP3, JP4, and JP6 are shorted. SW1 and SW2
should switch to the low position.
3. Turn on the power supply and measure VSYS using the DMM
across (+) and (-) TP5. VSYS should read 8.38V. The current
meter on the supply should read <100mA.Slowly increase
VIN from 5V to 15V. Monitor PH1 and PH2 to observe
seamless switching from Boost mode to Buck-Boost mode
and finally into Buck mode.
Input Current Limit Regulation
1. Keep VIN as a constant value between 3.8V and 24V. Set the
battery emulator voltage to 7.8V and connect the battery
emulator output to battery leads J5 and J6. Turn on the
battery emulator; there is no charge and discharge current for
the battery, which is consistent with the BGATE signal of a
high voltage level.
2. Add an electrical load on VSYS and GND terminals J3 and J4.
Turn on the load and increase the electrical load slowly; the
input current increases correspondingly and VSYS keeps
stable at 8.38V. The output voltage (VSYS) starts dropping as
the input current reaches the 1.5A input current limit. Refer
to the ISL9238 datasheet for more information about the
input current limit. If the VSYS voltage is 150mV lower than
the battery voltage, the BGATE FET turns on at a low voltage
level so that the battery supplies the current to the load.

UG074 Rev.2.00 Page 3 of 17
Nov 14, 2018
ISL9238EVAL1Z
FIGURE 2. GUI SNAPSHOT
FIGURE 3. EVALUATION BOARD CONNECTION GUIDELINE
(+) SUPPLY
(-) SUPPLY
USB PORT
FOR SMBus
PH1 PH2 (+) DMM
(-) DMM
(+) BATTERY
(-) BATTERY
BGATE
LED 1, 2, 3
BATGONE
LEAD
LEAD
LEAD
LEAD
LEAD
LEAD

UG074 Rev.2.00 Page 4 of 17
Nov 14, 2018
ISL9238EVAL1Z
Charging Mode
1. Set the power supply to a constant value between 3.8V and
24V, then complete Steps 1 and 2 in “System Voltage
Regulation” on page 2. Make sure the input current does not
reach the limit.
2. Set the battery emulator voltage to 7.8V and connect the
battery emulator output to battery leads J5 and J6.
3. Connect the USB cable at the USB port for the SMBus. LED 1,
2, and 3 all turn on.
4. Turn on the power supply; LED 3 turns off. Turn on the battery
emulator and open the ISL9238 GUI (shown in Figure 2 on
page 3).
Note: A green check mark in the USB Interface section of
the GUI indicates the GUI is ready to communicate with the
evaluation board. A red X in the USB Interface section
indicates the GUI is not ready to communicate with the
evaluation board. Click the Reset USB button until a green
check mark shows in the USB Interface. If a green check mark
does not appear, check the USB connection.
5. Select 2 Cell in the Battery Cell Configuration section and
click the Write All button. All controller register values are set
to the default values correspondingly. The system voltage is
8.4V, which is the value of MaxSysVoltage in the GUI. There is
no charge and discharge current for the battery.
6. Change the ChargeCurrentLimit from 0A to 2A and click the
Write button. The battery is now in a 2A current charge
configuration. The charge current value can be monitored in
the GUI by clicking the Read button in the ChargeCurrentLimit
section.Monitor the BGATE signal status to confirm the
battery is in Charging mode.
Note: Make sure the input current does not reach the input
current limit value, especially for a small VIN input.
Trickle Charging Mode
1. Complete Steps 1 through 6 in “Charging Mode”without any
changes.
2. Decrease the battery emulator voltage and monitor the
battery charging current. As long as the battery emulator
voltage is less than 5.2V (lower than SystemMinVoltage), the
battery enters trickle Charging mode and the charge current
decreases to 0.26A. The trickle charge current value can be
changed through the SMBus control registers. Refer to the
ISL9238 datasheet for more information.
Note: Make sure the input current does not reach the input
current limit value, especially for small VIN input.
OTG Mode
1. Set the battery emulator voltage to a constant value between
5.8V and 15V. Connect battery leads J5 and J6 with the output
disabled.
2. Connect the electric load on supply leads J1 and J2 with the
output disabled.
3. Connect the USB cable at the USB port for SMBus. Only the
LED 1 light is on. Turn on the battery emulator and electrical
load without adding any load.
4. Open the ISL9238 GUI. The OTGVoltage is the voltage value
for the load side, as shown in Figure 4 on page 5. The
OTGCurrent is the OTG output current limit at the load side.
These values can be set as needed within the output limit
range. Refer to the ISL9238 datasheet for the OTGVoltage
and OTGCurrent value ranges.
5. Select the Control0 & 1 Registers tab, enable the OTG
function in Control1 Register, and click the Write button, as
shown in Figure 5 on page 5.
6. Switch SW2 on the evaluation board to the HI position. The
load voltage is regulated as an OTGVoltage value, set in
Figure 4 on page 5, and the LED 3 light is on, indicating the
OTG function is enabled.
7. Increase the electrical load slowly and monitor the load
voltage. As long as the load current is less than the
OTGCurrent limit value, the load voltage is regulated at the set
value.

UG074 Rev.2.00 Page 5 of 17
Nov 14, 2018
ISL9238EVAL1Z
FIGURE 4. OTGVOLTAGE AND OTGCURRENT SETTINGS IN THE GUI
FIGURE 5. OTG FUNCTION ENABLE

UG074 Rev.2.00 Page 6 of 17 Nov 14, 2018
ISL9238EVAL1Z
ISL9238EVAL1Z Schematic
FIGURE 6. ISL9238EVAL1Z BOARD SCHEMATIC
FOR NO ASGATE OPTION
SDA, SCL, ACOK, PROCHOT#, BATGONE, OTGPG/CMOUT, OTGEN
all have 3V3 or VDD pull up options
For battery connector connection
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UG074 Rev.2.00 Page 7 of 17
Nov 14, 2018
ISL9238EVAL1Z
FIGURE 7. TOP OF BOARD
FIGURE 8. BOTTOM OF BOARD

UG074 Rev.2.00 Page 8 of 17
Nov 14, 2018
ISL9238EVAL1Z
Bill of Materials
QTY
REFERENCE
DESIGNATOR DESCRIPTION MANUFACTURER MANUFACTURER PART
1 SEE LABEL-RENAME BOARD PWB-PCB, ISL9237EVAL1Z, REVB, ROHS IMAGINEERING INC ISL9237EVAL1ZREVBPCB
4 C1, C2, C3, C4 CAP-POSCAP, SMD, 7.3x4.3x1.9, 47µF, 20V,
20%, 55mΩ, ROHS
SANYO 20TQC47MYF
1 C43 CAP, SMD, 0603, 10pF, 50V, 10%, NP0, ROHS VENKEL C0603COG500-100KDE
2 C45, C82 CAP, SMD, 0603, 1000pF, 16V, 10%, X7R, ROHS VENKEL C0603X7R160102KNE
4 C38, C84, C85, C86 CAP, SMD, 0603, 0.1µF, 25V, 10%, X7R, ROHS MURATA GRM188R71E104KA01D
9 C5, C6, C28, C29, C31, C34, C35, C81,
C83
CAP, SMD, 0603, 1µF, 25V, 10%, X5R, ROHS MURATA GRM188R61E105KA12D
1 C46 CAP, SMD, 0603, 0.022µF, 25V, 10%, X7R, ROHS MURATA GRM188R71E223KA01J
2 C30, C36 CAP, SMD, 0603, 0.22µF, 25V, 10%, X7R, ROHS TDK C1608X7R1E224K
1 C42 CAP, SMD, 0603, 4700pF, 16V, 10%, X7R, ROHS VENKEL C0603X7R160-472KNE
4 C26, C32, C33, C37 CAP, SMD, 0603, 4.7µF, 10V, 10%, X5R, ROHS VENKEL CR0603-16W-4701FT
0 C87 CAP, SMD, 0603, DNP-PLACE HOLDER, ROHS
17 C7-C16, C18, C21, C22, C23, C24, C40,
C41
CAP, SMD, 0805, 10µF, 25V, 10%, X5R, ROHS TDK C2012X5R1E106K
1 L1 PWR CHOKE COIL, SMD, 6.95x6.6, 2.2µH, 10A,
20%, ROHS
CYNTEC CO., LTD. PIMB063T-2R2MS-01
3 J1, J3, J5 CONN-GEN, BIND.POST, INSUL-RED, THMBNUT-
GND
JOHNSON
COMPONENTS
111-0702-001
3 J2, J4, J6 CONN-GEN, BIND.POST, INSUL-BLK,
THMBNUT-GND
JOHNSON
COMPONENTS
111-0703-001
2 TP13, TP14 CONN-SCOPE PROBE TEST PT, COMPACT, PCB
MNT, ROHS
TEKTRONIX 131-4353-00
51 TP1-TP12, TP15-TP37, TP43-TP58 CONN-MINI TEST POINT, VERTICAL, WHITE, ROHS KEYSTONE 5002
1 J10 CONN-USB MINI-B RECEPTACLE, TH, 5 CIRCUIT,
R/A, ROHS
MOLEX 54819-0519
1 JP6 CONN-HEADER, 1x3, BREAKAWY 1x36, 2.54mm,
ROHS
BERG/FCI 68000-236HLF
3 JP3, JP4, JP5 CONN-HEADER, 1x2, RETENTIVE, 2.54mm,
0.230x0.120, ROHS
BERG/FCI 69190-202HLF
3 JP3, JP4, JP6-Pins 1-2 CONN-JUMPER, SHORTING, 2PIN, BLACK, GOLD,
ROHS
SULLINS SPC02SYAN
1 D1 DIODE-RECTIFIER, SMD, SOT23, 30V, 200mA,
DUAL DIODE, ROHS
BAT54C-7-F-T
3 LED1, LED2, LED3 LED, SMD, 1206, GREEN, 75mW, 3mcd, 567nm,
ROHS
DIALIGHT 597-3311-407NF
1 U2 IC-USB MICROCONTROLLER, 32P, LQFP,
PROGRAMMED, ROHS
SILICON
LABORATORIES
C8051F320-GQ
1 U3 IC-ADJ.V, 1A LDO REGULATOR, 10P, DFN, 3x3,
ROHS
RENESAS ISL80101IRAJZ
1 U1 IC-NOTEBOOK BATTERY CHARGER, 32P, QFN,
4x4, ROHS
RENESAS ISL9238HRTZ
3 Q8, Q9, Q10 TRANSISTOR, N-CHANNEL, 3LD, SOT-23, 60V,
115mA, ROHS
DIODES, INC. 2N7002-7-F

UG074 Rev.2.00 Page 9 of 17
Nov 14, 2018
ISL9238EVAL1Z
3 Q5, Q6, Q7 (ALT: SISS27DN-T1-GE3-T) TRANSISTOR-MOS, P-CHANNEL, -30V, -35A, 8P,
PWRPAK, ROHS
VISHAY SI7625DN-T1-GE3
4 Q1, Q2, Q3, Q4 TRANSISTOR-MOS, N-CHANNEL, 8P, PWRPAK,
30V, 20A, ROHS
VISHAY SISA14DN-T1-GE3
5 R1, R2, R7, R10, R14 RES, SMD, 0603, 2Ω, 1/10W, 1%, TF, ROHS YAGEO 9C06031A2R00FGHFT
1 R8 RES, SMD, 0603, 4.7Ω, 1/10W, 1%, TF, ROHS VENKEL CR0603-10W-4R70FT
17 R4, R5, R6, R11, R12, R24, R40, R41,
R42, R43, R84, R85, R86, R89, R90,
R91, R92
RES, SMD, 0603, 0Ω, 1/10W, TF, ROHS VENKEL CR0603-10W-000T
4 R22, R83, R87, R88 RES, SMD, 0603, 1k, 1/10W, 1%, TF, ROHS PANASONIC ERJ-3EKF1001V
6 R15, R16, R36, R38, R39, R81 RES, SMD, 0603, 10k, 1/10W, 1%, TF, ROHS VENKEL CR0603-10W-1002FT
6 R13, R21, R28, R31, R44, R45 RES, SMD, 0603, 100k, 1/10W, 1%, TF, ROHS VENKEL CR0603-10W-1003FT
1 R23 RES, SMD, 0603, 133k, 1/10W, 1%, TF, ROHS VENKEL CR0603-10W-1333FT
3 R32, R33, R34 RES, SMD, 0603, 220Ω, 1/10W, 1%, TF, ROHS YAGEO RC0603FR-07220RL
1 R9 RES, SMD, 0603, 402k, 1/16W, 1%, TF, ROHS PANASONIC ERJ-3EKF4023V
1 R82 RES, SMD, 0603, 5.62k, 1/10W, 1%, TF, ROHS PANASONIC ERJ-3EKF5621V
1 R25 RES, SMD, 0603, 6.04k, 1/10W, 1%, TF, ROHS VENKEL CR0603-10W-6041FT
1 R27 RES, SMD, 0603, 698Ω, 1/10W, 1%, TF, ROHS PANASONIC ERJ-3EKF6980V
1 RS2 RES-CURR.SENSE, SMD, 1206, 0.01Ω, 1W, 1%,
75ppm, ROHS
VISHAY/DALE WSLP1206R0100FEA
1 RS1 RES-CURR.SENSE, SMD, 1206, 0.02Ω, 1W, 1%,
75ppm, ROHS
VISHAY/DALE WSLP1206R0200FEA
2 SW1, SW2 SWITCH-TOGGLE, SMD, 6PIN, SPDT, 2POS,
ON-NONE-ON, ROHS
ITT INDUSTRIES/
C&K DIVISION
GT11MSCBE
4 Four corners SCREW, 4-40x1/4in, PHILLIPS, PANHEAD,
STAINLESS, ROHS
BUILDING FASTENERS PMSSS 440 0025 PH
4 Four corners STANDOFF, 4-40x3/4in, F/F, HEX, ALUMINUM,
0.25 OD, ROHS
KEYSTONE 2204
1 Place assembly in bag BAG, STATIC, 5x8, ZIPLOC, ROHS RENESAS 212403-013
0 C19, C20, C25, C27, C39, C44,
C88-C97
DO NOT POPULATE OR PURCHASE
0 JP1, JP2 DO NOT POPULATE OR PURCHASE
0 L2 DO NOT POPULATE OR PURCHASE
0 R3, R35, R37 DO NOT POPULATE OR PURCHASE
0 TP38-TP42 DO NOT POPULATE OR PURCHASE
1 AFFIX TO BACK OF PCB LABEL-DATE CODE_LINE 1: YRWK/REV#, LINE 2:
BOM NAME
RENESAS LABEL-DATE CODE
1 RENAME PCB TO: ISL9238EVAL1Z. LABEL, TO RENAME BOARD RENESAS LABEL-RENAME BOARD
Bill of Materials
QTY
REFERENCE
DESIGNATOR DESCRIPTION MANUFACTURER MANUFACTURER PART

UG074 Rev.2.00 Page 10 of 17
Nov 14, 2018
ISL9238EVAL1Z
PCB Layout Guidelines
PIN NUMBER PIN NAME LAYOUT GUIDELINES
BOTTOM PAD
33
GND Connect the ground pad to the ground plane through a low impedance path. Use at least five vias to connect to the
ground planes in the PCB to ensure sufficient thermal dissipation directly under the IC.
1 CSON Run two dedicated traces with sufficient width parallel to (close to each other to minimize the loop area) the two
terminals of the battery current-sensing resistor to the IC. Place the differential mode and common-mode RC filter
components in the general proximity of the controller.
Route the current-sensing traces through vias to connect the center of the pads, or route the traces into the pads
from the inside of the current-sensing resistor. The following drawings show the two preferred ways of routing
current-sensing traces.
2CSOP
3 VSYS Signal pin that provides feedback for the system bus voltage. Place the optional RC filter in the general proximity of
the controller. Run a dedicated trace from the system bus to the pin and do not route near the switching traces. Do
not share the same trace with the signal routing to the DCIN pin OR diodes.
4 BOOT2 Switching pin. Place the bootstrap capacitor in the general proximity of the controller. Use sufficiently wide trace. Do
not allow any sensitive analog signal traces to cross over or get close to this pin.
5 UGATE2 Run the UGATE2 and PHASE2 traces in parallel with sufficient width. Do not allow any sensitive analog signal traces
to cross over or get close to this pin. Renesas recommends routing the PHASE2 trace to the high-side MOSFET source
pin instead of general copper.
Place the IC close to the switching MOSFET’s gate terminals and keep the gate drive signal traces short for a clean
MOSFET drive. The IC can be placed on the opposite side of the switching MOSFETs.
Place the output capacitors as close as possible to the switching high-side MOSFET drain and the low-side MOSFET
source. Use the shortest PCB trace connection. Place the capacitors on the same PCB layer as the MOSFETs instead
of on different layers and using vias to make the connection.
Place the inductor terminal to the switching high-side MOSFET drain and low-side MOSFET source terminal as close
as possible. Minimize this phase node area to lower the electrical and magnetic field radiation, but make this phase
node area large enough to carry the current. Place the inductor and the switching MOSFETs on the same layer of the
PCB.
6PHASE2
7 LGATE2 Switching pin. Run the LGATE2 trace parallel to the UGATE2 and PHASE2 traces on the same PCB layer. Use sufficient
width. Do not allow any sensitive analog signal traces to cross over or get close to this pin.
8 VDDP Place the decoupling capacitor in the general proximity of the controller. Run the trace connecting to the VDD pin
with sufficient width.
9 LGATE1 Switching pin. Run the LGATE1 trace parallel to the UGATE1 and PHASE1 traces on the same PCB layer. Use sufficient
width. Do not allow any sensitive analog signal traces to cross over or get close to this pin.
CURRENT-SENSING TRACES
VIAS
CURRENT-SENSING TRACES