Texas Instruments bq2435 Series User manual

User's GuideSLUU365 – June 2009
bq2435x DSG EVM for Li-Ion Charger Front-End
Protection IC
This user's guide describes the features, setup, and operation of the bq2435xEVM evaluation module.Included are the bill of materials, board layout, and schematic.
Contents1 Introduction ................................................................................................................... 21.1 General Description ................................................................................................ 21.2 EVM Features ....................................................................................................... 21.3 I/O Description ...................................................................................................... 21.4 Controls and Key Parameters Setting............................................................................ 21.5 Recommended Operating Conditions ............................................................................ 32 Test Summary ................................................................................................................ 32.1 Definitions ............................................................................................................ 32.2 Equipment ........................................................................................................... 32.3 Equipment Setup.................................................................................................... 42.4 Procedure ............................................................................................................ 53 PCB Layout Guideline ....................................................................................................... 64 Bill of Materials, Board Layout, and Schematic .......................................................................... 64.1 Bill of Materials ...................................................................................................... 64.2 Board Layout ........................................................................................................ 74.3 Schematic .......................................................................................................... 10
List of Figures
1 Original Test Setup for HPA398 (bq2435x DSG EVM) ................................................................. 52 Top Layer ..................................................................................................................... 73 Bottom Layer ................................................................................................................. 84 Top Silk Screen .............................................................................................................. 85 Top Assembly ................................................................................................................ 96 bq243550 Schematic ...................................................................................................... 10
List of Tables
1 Bill of Materials ............................................................................................................... 6
SLUU365 – June 2009 bq2435x DSG EVM for Li-Ion Charger Front-End Protection IC 1Submit Documentation Feedback

1 Introduction
1.1 General Description
1.2 EVM Features
1.3 I/O Description
1.4 Controls and Key Parameters Setting
Introduction www.ti.com
The bq2435x evaluation module (EVM) is a complete charger module for evaluating a charger front-endprotection and charger solution using the bq2435x and bq2057C devices. It is designed to deliver up to560 mA of charge current to Li-ion or Li-polymer applications. The charger front-end protection current isdesigned to 1.2 A.
The bq2435x protects the charging system against three types of failures: input overvoltage when the acadapter fails to regulate its voltage, load overcurrent when failures such as a short circuit occur in thecharging system, and battery overcharge.
For details, see the bq2435x data sheet (SLUS943 ).
•Evaluation module for bq2435x DSG•Evaluation module for bq2057C charger integrated circuit (IC)•Input operating range for bq2435x 4.5 V–26 V•Input operating range for bq24080 4.5 V–6.5 V•Input overvoltage protection.•Input overcurrent protection.•Battery overvoltage protection.•LED Indication for status signals.•Test points for key signals available for testing purpose. Easy probe hook-up•Jumpers available. Easy to change connections
Jack Description
J1–DC+ AC adapter, positive outputJ1–DC– AC adapter, negative output, groundJ2–FAULT bq24355 FAULT pinJ2–VBAT bq2435x VBAT pinJ2–GATDRV bq2435x GATDRV pinJ2–CHGIN bq2435x CHGIN pinJ3–BATEN bq24355 BATEN pinJ3–OUT bq2435x OUT pinJ3–BAT+ Battery positive outputJ3–GND GroundJ4–BAT+ Connect to battery positive outputJ4–BAT– Connect to battery negative output, ground
Jack
(1)
Description Factory Setting
JP1 If on, high-side current sensing resistor is disabled Jumper onJP2 bq24355 BATEN pin logic input, pull low to enable Jumper ( BATEN, GND) onJP3 bq2435x GATDRV pin Jumper offJP4 bq2057C BAT pin connection to bq2435x Jumper on
(1)
Short JP1, JP4, JP5, and JP6, and disconnect JP7 to use on board bq2057C as charger; to use external charger to controlbq2435x, disconnect JP1, JP4, JP5, and JP6 and short JP7.
2bq2435x DSG EVM for Li-Ion Charger Front-End Protection IC SLUU365 – June 2009Submit Documentation Feedback

1.5 Recommended Operating Conditions
2 Test Summary
2.1 Definitions
2.2 Equipment
2.2.1 Power Supplies
www.ti.com Test Summary
Jack
(1)
Description Factory Setting
JP5 bq2057C VCC pin connection to bq2435x Jumper onJP6 bq2057C CC pin connection to bq2435x Jumper onJP7 If on, low-side current sensing resistor is disabled Jumper off
Symbol Description Minim Typical Maxim Unitum um
Supply voltage, V
IN
Input voltage from ac adapter input 4.5 5 26 VBattery voltage, V
BAT
Voltage applied at VBAT terminal of J4 0 3–4.2 5 VSupply current, I
AC
Maximum input current from ac adapter input 0 1.5 ACharge current, I
chrg
Battery charge current 0.05 0.56 1 AOperating junction temperature 0 125 °Crange, T
J
This procedure details how to configure the evaluation board. On the test procedure, the following namingconventions are followed. See the schematic for details.
VXXX External voltage supply name (VIN, VBAT, VOUT)LOADW: External load name (LOADR, LOADI)V(TPyyy) : Voltage at internal test point TPyyy. For example, V(TP1) means the voltage atTP1.V(Jxx): Voltage at jack terminal Jxx.V(TP(XXXXX)): Voltage at test point “XXXXX”. For example, V(ACDET) means the voltage atthe test point which is marked as “ACDET”.V(XXX, YYY): Voltage across point XXX and YYY.I(JXX(YYY)): Current going out from the YYY terminal of jack XX.Jxx(BBB): Terminal or pin BBB of jack xxJxx ON : Internal jumper Jxx terminals are shortedJxx OFF: Internal jumper Jxx terminals are openJxx (-YY-) ON: Internal jumper Jxx adjacent terminals marked as “YY” are shortedMeasure: →A,B Check specified parameters A, B. If measured values are not within specifiedlimits the unit under test has failed.Observe →A,B Observe if A, B occur. If they do not occur, the unit under test has failed.
Assembly drawings have location for jumpers, test points and individual components
Power Supply 1 (PS 1): a power supply capable of supplying 10 V at 2 A is required.
SLUU365 – June 2009 bq2435x DSG EVM for Li-Ion Charger Front-End Protection IC 3Submit Documentation Feedback

2.2.2 Load 1
2.2.3 Load 2
2.2.4 Meters
2.2.5 Wire Gauge
2.3 Equipment Setup
Test Summary www.ti.com
A 10-V (or above), 2-A (or above) electronic load that can operate at constant current mode.
A 10-V (or above), 2-A (or above) electronic load that can operate at constant voltage mode.
Four Fluke 75 multimeters (equivalent or better)Or:
Three equivalent voltage meters and one equivalent current meterThe current meter must be capable of measuring 2-A+ current.
All wires connected to the EVM input power supply and output load must use at least AWG 22. Themaximum current is up to 1 A.
1. Set the PS 1 for 0 V ±100 mVdc, 2 ±0.1 A current limit, and then disable the output.2. Connect the output of PS 1 to J1 (DC+, DC–).3. Connect a voltage meter across J1 (DC+, DC–).4. Connect the output of the Load 1 in series with a current meter (multimeter) to J2 (CHGIN) and J3(GND). Turn on the power of the Load 1. Set the load current to 1.5 A ±50 mA but disable the output.5. Connect output of the Load 2 in series with a current meter (multimeter) to J4 (BAT+, BAT–).6. Connect a voltage meter across J4 (BAT+, BAT–).7. Set the voltage of Load 2 to 3.6 V ±0.1 V, and disable output of Load 2.8. JP1: ON, JP2 (BATEN, GND): ON, JP3: OFF, JP4: ON, JP5: ON, JP6: ON, JP7: OFF.
After the preceding steps have been taken, the test setup for HPA398 (bq2435x DSG EVM) appears as isshown in Figure 1 .
4bq2435x DSG EVM for Li-Ion Charger Front-End Protection IC SLUU365 – June 2009Submit Documentation Feedback

U1
U2
CFET APPLICATION
CIRCUIT
JP1
JP2JP3
JP4
JP5JP6
JP7
J4
BAT-
BAT+
DC-
DC+
FAULT
VBAT
GND
OUT
CHGIN
J3J2
J1
HPA398 bq243 EVM5x
BAT+
GATDRV
BATEN
V
Power
Supply 1
Load
2
V
I
Ibat
Load
1
I
I
2.4 Procedure
2.4.1 Charger Current and Voltage Regulation
2.4.2 CFET Input Overvoltage Protection
2.4.3 CFET Load Overcurrent Protection
www.ti.com Test Summary
Figure 1. Original Test Setup for HPA398 (bq2435x DSG EVM)
1. Ensure that steps in Section 2.3 are followed.2. Enable output of PS 1.3. Increase the output voltage of PS 1 to 5 V ±0.1 V.4. Enable output of Load 2.Measure →V(J2(OUT)) = 3.6 V ±200 mVMeasure →Ibat = 560 mA ±70 mAObserve →D2 on, D3 on, D6 off, D7 on.
1. Increase the voltage of PS 1 to 8 V ±0.1 V.Observe →D2 on, D3 off, D6 off, D7 off.2. Decrease the voltage of PS 1 to 5 V ±0.1 V.Observe →D2 on, D3 on, D6off, D7 on.
1. Enable the output of the Load 1.Observe →D2 on, D3 off, D6 off, D7 off.2. Disable the output of the Load 1.Observe →D2 on, D3 on, D6 off, D7 on.3. Decrease the voltage of PS 1 to 0 V ±0.1 V.
SLUU365 – June 2009 bq2435x DSG EVM for Li-Ion Charger Front-End Protection IC 5Submit Documentation Feedback

3 PCB Layout Guideline
4 Bill of Materials, Board Layout, and Schematic
4.1 Bill of Materials
PCB Layout Guideline www.ti.com
1. It is critical that the exposed power pad on the backside of the bq2435x package be soldered to theprinted-circuit board (PCB) ground. Ensure that sufficient thermal vias are located underneath the IC,connecting to the ground plane on the other layers.2. The high-current charge paths into ACIN and from CHGIN, OUT pins must be sized appropriately forthe maximum charge current in order to avoid voltage drops in these traces.3. Decoupling capacitors for ACIN, CHGIN must be placed and make the interconnections to the IC asshort as possible.4. Resistors for VBAT pin must be placed close to the corresponding IC pins and make theinterconnections to the IC as short as possible.
Table 1. Bill of Materialsbq24350 bq24352 - bq24355 - RefDes Value Description Size Part Number MFR-001 002 003
1 1 1 C1 1uF Capacitor, Ceramic, 35V, 603 Std StdX5R, 10%
3 3 3 C2, C3, C5 1uF Capacitor, Ceramic, 10V, 603 Std StdX7R, 10%
1 1 1 C4 0.1uF Capacitor, Ceramic, 16V, 805 Std StdX7R, 10%
1 1 1 C6 0.1uF Capacitor, Ceramic, 10V, 603 Std StdX7R, 10%
1 1 1 C7 220uF Capacitor, Electrolytic, 25V, 0.327 X 0.327 UUD1E221MNL1GS Nichicon20% inch
1 1 1 D1 BZT52C6V8S Diode, Zener, 200mW, 6.8V SOD-323 BZT52C6V8S General
3 3 3 D2, D3, D6 Green Diode, LED, Green, 2.1-V, 603 LTST-C190GKT Lite On20-mA, 6-mcd
2 2 2 D4, D7 Red Diode, LED, Red, 2.1-V, 603 LTST-C190CKT Lite On20-mA, 6-mcd
1 1 1 D5 BAT54C Diode, Dual Schottky, SOT23 BAT54C Vishay-200-mA, 30-V Liteon
2 2 2 J1, J4 ED1514/2DS Terminal Block, 2-pin, 6-A, 0.27 x 0.25 ED1514/2DS OST3.5mm inch
2 2 2 J2, J3 ED1516/4DS Terminal Block, 4-pin, 6-A, 0.55 x 0.25 ED1516/4DS OST3.5mm inch
5 5 5 JP1, JP4, PEC02SAAN Header, 2-pin, 100mil 0.100 inch x 2 PEC02SAAN SullinsJP5, JP6, spacingJP7
2 2 2 JP2, JP3 PTC03SAAN Header, Male 3-pin, 100mil 0.100 inch x 3 PTC03SAAN Sullinsspacing, (36-pin strip)
5 5 5 JP1, JP2, 929950-00 Shorting jumpers, 2-pin, 929950-00 3M/ESDJP4, JP5, 100mil spacing,JP6
2 2 0 R1, R2 0 Resistor, Chip, 1/16W, 1% 402 Std Std
0 0 2 R3, R4 0 Resistor, Chip, 1/16W, 1% 402 Std Std
2 2 2 R5, R6 200k Resistor, Chip, 1/16W, 5% 402 Std Std
2 2 2 R7, R8 200k Resistor, Chip, 1/16-W, 5% 603 Std Std
2 2 2 R9, R10 0.2 Resistor, Metal Film, 1/4 watt, 1206 Std Std1%
1 1 1 R11 20k Resistor, Chip, 1/16-W, 5% 603 Std Std
1 1 1 R12 1k Resistor, Chip, 1/16-W, 5% 603 Std Std
1 1 1 R13 100 Resistor, Chip, 1/16-W, 5% 603 Std Std
1 1 1 R14 6.2k Resistor, Chip, 1/16-W, 5% 603 Std Std
4 4 4 R15, R16, 1.5k Resistor, Chip, 1/16-W, 5% 603 Std StdR17, R18
6bq2435x DSG EVM for Li-Ion Charger Front-End Protection IC SLUU365 – June 2009Submit Documentation Feedback

4.2 Board Layout
www.ti.com Bill of Materials, Board Layout, and Schematic
Table 1. Bill of Materials (continued)bq24350 bq24352 - bq24355 - RefDes Value Description Size Part Number MFR-001 002 003
1 1 1 R19 51 Resistor, Chip, 1/16-W, 5% 603 Std Std
4 4 4 6-32 NYL nuts NY HN 632 H620-ND Building
Fasteners
4 4 4 ST1,ST2,S 4816 STANDOFF M/F HEX 6-32 sf_thvt_325_rn 4816 KeystoneT3,ST4 NYL .500" d
8 8 8 TP1, TP2, white Test Point, White, Thru Hole 0.100 x 0.100 5002 KeystoneTP3, TP4, Color Keyed inchTP5, TP6,TP7, TP8
1 1 1 TP9 white Test Point, White, Thru Hole 0.100 x 0.100 5001 KeystoneColor Keyed inch
1 0 0 U1 bq24350DSG IC, OVER-VOLTAGE AND SON-8 BQ24350DSG TIOVER-CURRENT
CHARGER FRONT-END
0 1 0 U1 bq24352DSG IC, OVER-VOLTAGE AND SON-8 BQ24352DSG TIOVER-CURRENT
CHARGER FRONT-END
0 0 1 U1 bq24355DSG IC, OVER-VOLTAGE AND SON-8 BQ24355DSG TIOVER-CURRENT
CHARGER FRONT-END
1 1 1 U2 BQ2057CSN IC, Charge Management, S0-8 BQ2057CSN TIOne or Two Cell Li-Ion orLi-Pol Charger
1 1 1 -- HPA398 PCB, 2.8 In x 2.8 In x 0.062 PCB AnyIn
Notes: 1. Number 0 in left side columns means do not use this component.
2. OPEN in value column means do not use this component.
3. Std in part number column means standard manufacturer’s part number.
4. Std in MFR column means standard manufacturer.
Figure 2. Top Layer
SLUU365 – June 2009 bq2435x DSG EVM for Li-Ion Charger Front-End Protection IC 7Submit Documentation Feedback

Bill of Materials, Board Layout, and Schematic www.ti.com
Figure 3. Bottom Layer
Figure 4. Top Silk Screen
8bq2435x DSG EVM for Li-Ion Charger Front-End Protection IC SLUU365 – June 2009Submit Documentation Feedback

www.ti.com Bill of Materials, Board Layout, and Schematic
Figure 5. Top Assembly
SLUU365 – June 2009 bq2435x DSG EVM for Li-Ion Charger Front-End Protection IC 9Submit Documentation Feedback

4.3 Schematic
+
Bill of Materials, Board Layout, and Schematic www.ti.com
Figure 6. bq243550 Schematic
10 bq2435x DSG EVM for Li-Ion Charger Front-End Protection IC SLUU365 – June 2009Submit Documentation Feedback