TI BQ2028

bq2028
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SLUSB22B – OCTOBER 2012 – REVISED NOVEMBER 2012
4Kb EEPROM with Single-Wire HDQ Interface and Temperature Sensor
Check for Samples: bq2028
FEATURES
DESCRIPTION
•
The Texas Instruments bq2028 serial 4Kb nonvolatile
memory (EEPROM) with integrated temperature
sensor and LDO linear regulator provides pack-side
memory storage and temperature monitoring for a
single-cell system-side battery fuel gauge solution
such as the bq27505-E1.
1
•
•
•
•
Serial Non-Volatile Memory (NVM)
– 512 Byte (4Kb) EEPROM
– Provides Battery Pack NVM storage for
bq27505-E1 Fuel Gauge:
– Manufacturing Data
– Operational History
– Resistance Tables
– State of Health Information
Single Wire HDQ Communications Port
Integrated 2.5V LDO Linear Regulator
– Ultra-low power “shutdown” mode (1µA
Typical) via auto-timeout and/or host
command
– Wake up from shutdown via HDQ break
Internal Die-Temperature Sensor
– ±5°C Range = –40°C to 85°C
– Raw AD to Temperature Conversion
Performed by Host Firmware
Package
– 12-pin, 1490 × 2350 µm WCSP (YZG),
0.625mm Max Thickness, 0.5mm Pitch
The bq2028 communicates with the bq27505-E1
gauge over a single-wire HDQ interface with a
minimal overhead protocol yet ensures error free data
transfer.
REGIN
bq2028
2.5-V
LDO
HDQ
VDD
HDQ and control
512 x 8b
EEPROM
Internal
temperature
sensor
VSS
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2012, Texas Instruments Incorporated
bq2028
SLUSB22B – OCTOBER 2012 – REVISED NOVEMBER 2012
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These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
DEVICE INFORMATION
AVAILABLE OPTIONS
PRODUCTION PART #
bq2028YZGR
bq2028YZGT
PACKAGE
TA
TAPE and REEL QUANTITY
12-pin WCSP
–40°C to 85°C
3000
250
PIN ASSIGNMENT
CSP-12
(bottom view)
D3
C3
B3
A3
D2
C2
B2
A2
D1
C1
B1
A1
Figure 1. bq2028 Pin Assignment (Bottom View)
PIN DESCRIPTIONS
PIN NAME
CSP-12 PIN
I/O
DESCRIPTION
TEST3
C3
I/O
Reserved for factory test. Connect to VSS in application circuit.
REGIN
D3
P
Regulator input. Typically connected to battery CELL+.
VDD
D2
P
Regulator 2.5V output. Decouple with a 0.47µF cap to VSS.
VSS
A1, B1, D1, B2,
C2
P
Ground pin.
HDQ
A2
I/O
HDQ Data pin. Open-drain I/O. Requires external pull-up for proper operation.
TEST1
C1
I/O
Reserved for factory test. Connect to VSS in application circuit.
TEST0
B3
I/O
Reserved for factory test. Connect to VSS in application circuit.
TEST2
A3
I/O
Reserved for factory test. Connect to VSS in application circuit.
2
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ELECTRICAL SPECIFICATIONS
ABSOLUTE MAXIMUM RATINGS
over operating free-air temperature range (unless otherwise noted) (1)
VALUE
UNIT
MIN
MAX
VREGIN
Supply voltage range
–0.3
5.5
V
HDQ
Open-drain I/O pin
–0.3
5.5
V
VI
Input voltage range to all other pins (TEST0-3)
–0.3
VREG25 + 0.3
V
ESD
HBM for pins other than TEST1, TEST2, TEST3
2
kV
TA
Operating free-air temperature range
–40
85
°C
TF
Functional temperature
–40
100
°C
Tstg
Storage temperature range
–65
150
°C
(1)
Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratings
only, and functional operation of the device at these or any other conditions beyond those indicated under recommended operating
condition” is not implied. Exposure to absolute–maximum–rated conditions for extended periods may affect device reliability.
RECOMMENDED OPERATING CONDITIONS
TA = 25°C, CLDO25 = 0.47 µF, VREGIN = 3.6V (unless otherwise noted)
VREGIN
Supply Voltage
MIN
TYP MAX
2.45
4.5
UNIT
V
RPUEXT
HDQ external pull-up
To system-side 2.5V LDO output. Recommend using
10kΩ, 5% resistor.
CHDQ
HDQ capacitive loading
Total external bus capacitance
50
CREGIN
External input capacitor for internal LDO
between REGIN and VSS
0.1
µF
CLDO25
External output capacitor for internal
LDO between VDD and VSS
Nominal capacitor values specified. Recommend a 5%
ceramic X5R type capacitor located close to the
device.
0.47
µF
10
22
kΩ
250
pF
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DC ELECTRICAL CHARACTERISTICS
TA = –40°C to 85°C, CLDO25 = 0.47 µF, VREGIN = 3.6 V (unless otherwise noted)
PARAMETER
TEST CONDITION
MIN
TYP
MAX
UNIT
SUPPLY CURRENT
SHUTDOWN Mode (LDO = off)
SLEEP Mode (LFO = on; HFO = off)
ICC
Supply Current
(1)
IDLE Mode (LFO, HFO = on; CONV= 0)
TEMP Read (LFO, HFO = on; CONV = 1)
1
2
20
50
55
110
110
200
EEPROM Read (LFO, HFO = on)
300
600
EEPROM Write (LFO, HFO = on)
2300
5000
2.5
2.6
µA
2.5V LDO REGULATOR
VREG25
Regulator output voltage
2.7 V ≤ VREGIN ≤ 4.5 V, IOUT ≤ 10 mA
2.4
2.45 V ≤ VREGIN < 2.7 V (low battery), IOUT ≤ 3 mA
2.4
V
OTHER ANALOG: POWER ON RESET, TEMPERATURE SENSOR, INTERNAL VOLTAGE REFERENCE
VPOR+
POR Threshold
Positive-going input at VDD, TA = 25°C
2.05
2.20
2.31
V
VHYSPOR
POR Hysteresis
TA=25°C
45
115
185
mV
VWU+
HDQ Wakeup threshold
Positive-going input at HDQ, TA = 25°C
1.2
VHYSWU
HDQ Wakeup hysteresis
TA = 25°C
VASD
Auto shutdown threshold
VHYSASD
Auto shutdown hysteresis
V(TEMP)
Temperature sensor
1.4
V
505
mV
2.05
2.20
2.31
45
115
185
–1.986
V
V
mV/°C
HDQ INTERFACE
VIH
Input voltage high
VIL
Input voltage low
VOH
Output voltage high
Open drain, external pull up to VDD
VOL
Output voltage low
Open-drain IOL = 1mA
CI
Input capacitance
Iitot
HDQ input total current
Includes leakage plus internal pull-down
2
µA
IOL
Output low sink current
VOL = 0.4V
1
mA
RPDINT
HDQ internal pull-down
For auto-shutdown
5
MΩ
(1)
4
1.8
V
0.6
VDD–0.5
V
0.4
10
1.25
V
2.5
V
pF
An EEPROM write operation is required for proper device initialization following exit from SHUTDOWN, SLEEP, or POWER-ON RESET.
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AC ELECTRICAL CHARACTERISTICS
TA = –40°C to 85°C, CLDO25 = 0.47 µF, VREGIN = 3.6V (unless otherwise noted)
PARAMETER
TEST CONDITION
MIN
TYP
MAX
UNIT
EEPROM
Array Size
128 words x 32 bits = 4Kbits
512
Write Cycle Endurance
Bytes
1000
K cycles
HDQ Data Access
Via 32 bit BUFFER
8
Program time
Per word (internal timing only)
6
20
Bits
mS
Read time
Per word (internal timing only)
300
2000
nS
HDQ INTERFACE AND MISCELLANEOUS (Refer to Figure 6 and Figure 7)
tB
Break time
tBR
Break recovery time
tSLWU
SLEEP wakeup
tSHWU
SHUTDOWN wakeup
Host drives HDQ Break. Timed from rising edge of first wakeup
break pulse to falling edge of next break pulse with first data.
tSHUTDN
SHUTDOWN time
Time delay after VASD threshold is met before SHUTDOWN mode is
entered.
tASHWU
AUTOSHUTDOWN wakeup
Time delay after VASD threshold is met or 2 second timeout is met
before Host can drive HDQ break for wakeup.
tPORWU
POR wakeup
Power on reset wakeup time before device is ready to receive first
HDQ message
st
190
µs
40
µs
200
µs
20
ms
2
10
S
2
10
S
35
ms
tREGINHDQ
REGIN to HDQ
REGIN valid to 1 rising edge of HDQ to POR device. (Figure 3)
tPOR
POR
VDD ramp to POR release.(Figure 3)
15
ms
tGRST
Global reset
POR release to GRST release. (Figure 3)
tHW1
Host Write 1 time
Host drives HDQ
5
50
µs
tHW0
Host Write 0 time
Host drives HDQ
86
145
µs
tCYCH
Host cycle time
Host drives HDQ
190
tDW1
Device Write 1 time
bq2028 drives HDQ
39
41
43
µs
tDW0
Device Write 0 time
bq2028 drives HDQ
106
111
116
µs
tCYCD
Device cycle time
bq2028 drives HDQ
197
207
217
µs
tRSPS
Device response time
bq2028 drives HDQ
211
222
233
µs
tHDQSTDET
HDQ Start detect
bq2028 filters out very short HDQ pulses
1.98
µs
11
4
ms
ms
µs
0
A/D CONVERTER
f(SAMPLE)
Sampling frequency
t(CONV)
Conversion time
V(ADC_IN)
Input voltage range
Delta Sigma modulator frequency
65.5
SPEED[1:0] = 00
125
SPEED[1:0] = 01
62.50
SPEED[1:0] = 10
31.25
SPEED[1:0] = 11
Internal Vref, TA = 25°C, VTEMP internal channel only
kHz
ms
7.8125
–0.2
1
V
HIGH FREQUENCY OSCILLATOR (HFO)
HFOSC
Operating frequency
HFERR
Frequency error
HFSTART
Start-up time
8.389
TA = –40°C to 85°C
–8.0%
MHz
8.0%
14
200
µs
LOW FREQUENCY OSCILLATOR (LFO)
LFOSC
Operating frequency
LFERR
Frequency error
LFSTART
Start-up time
32.768
TA = –40°C to 85°C
–8.0%
kHz
8.0%
100
500
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μs
5
bq2028
SLUSB22B – OCTOBER 2012 – REVISED NOVEMBER 2012
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BLOCK DIAGRAM
PACK+
VSYS
REGIN
2.5V
LDO
BAT
bq2028
VCC
HDQ
DATA
SDA
VDD
2.5V
LDO
LFO
Optional
TEST0
VCC
SCL
HDQ & Control
HFO
TEST1
bq27505-E1
Host Controller
HDQ
Wakeup /
POR
+
TEST2
BI/TOUT
TEST3
SOC_INT
BAT_LOW
128 x 32b
EEPROM
To System / Charger
TS
Internal
Temp.
Sensor
VSS
SRP
VSS
T
SRN
_
10-Bit
ADC
VCC
VM
Low-Side
Protector
CHG
VSS
DSG
PACK-
10mΩ
Figure 2. bq2028 Block Diagram
Power Modes
The bq2028 has multiple operational modes for reduced power consumption. defines which circuits are enabled
in each of these operational modes.
Table 1. Power Mode Table (1)
(1)
6
CIRCUIT
SHUT-DOWN
SLEEP
IDLE
HDQ
READ/WRITE
TEMP
READ
EEPROM
READ
EEPROM
WRITE
Wakeup/POR
√
√
√
√
√
√
√
LDO Regulator
–
√
√
√
√
√
√
32kHz LFO
–
√
√
√
√
√
√
8MHz HFO
–
–
√
√
√
√
√
HDQ Interface
–
–
–
√
√
√
√
ADC
–
–
–
–
√
–
–
EEPROM Read
–
–
–
–
–
√
–
EEPROM Write
–
–
–
–
–
–
√
√: Active spacer –: Not in use
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SLUSB22B – OCTOBER 2012 – REVISED NOVEMBER 2012
tPORWU
tREGINHDQ
tGRST
tPOR
REGIN
HDQ
VDD
POR
1
GRST
(1)
Internal digital core reset, held for 4 ms after analog POR deasserted
Figure 3. Power Up Sequence
tSHWU
tGRST
tPOR
REGIN
HDQ
VDD
POR
1
GRST
(1)
Internal digital core reset, held for 4 ms after analog POR deasserted
Figure 4. Shutdown Wake Up Sequence
HDQ Interface
The bq2028 supports a single-wire, open-drain communication interface that supports the HDQ protocol as
shown in Figure 5. The HDQ protocol is based on the Texas Instruments HDQ standard as discussed in the TI
application report (SLUA408A) (http://focus.ti.com.cn/cn/lit/an/slua408a/slua408a.pdf ).
The communication protocol is asynchronous return-to-one referenced to Vss. A passive pullup resistance is
required to pull the HDQ line to a high state when neither the host nor the slave is pulling the line low during twoway communication over the single wire interface. The interface uses a command-based protocol, where the
host sends a command byte to the HDQ slave device. The command directs the slave to either receive or
transmit the next byte of data. The last transmitted bit of the command byte determines the direction of the data
(read or write) as shown in Figure 7.
bq275XX
(HDQ master)
bq27528
(HDQ slave)
VDD
HDQ
Figure 5. HDQ Interface Connections (single wire configuration)
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SLUSB22B – OCTOBER 2012 – REVISED NOVEMBER 2012
tB
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tBR
tDW0
tHW0
tDW1
tHW1
tCYCD
tCYCH
tB
tSLWU, tSHWU
tB
tBR
Figure 6. HDQ Detailed Timing Waveform
tRSPS
HDQ 8-bit data from HDQ slave
Command byte from HDQ master
7-bit address
BREAK
D0
D1
D3
D2
8-bit data
R/W bit
D4
D5
D6
D0
D7
D1
D3
D2
D5
D4
D6
D7
D7=1, Write
D7=1, Read
Figure 7. HDQ 8-bit Mode Read Cycle
Device Control
Using a register address access method, the HDQ command byte limits addressing to 7 bits so a mapping
scheme is necessary to differentiate device control and status registers from EEPROM data. This register and
paged EEPROM access scheme is shown in Figure 8.
0x0B
ADLOW
~3.5-ms HDQ transfer
(LSBs shifted first)
CRCT
(Target)
READ
C[1:0]
R[3:0]
M
W/R
HDQ8
host
0x0A
0x03
Buffer[3]
0x04
CRCR
(Result)
0x21
D[7:0]
WRITE
Buffer[2]
0x01
Buffer[1]
0x09
Status
0x08
ADCTL2
ADCTL1
HDQ registers
0x20
0x02
Control
ADHI
0x00
Buffer[0]
0X0D
Row
[3:0]
0x07
Page
[2:0]
0X31
PageEn
[7:0]
C[1:0]
R[
3:
0
BUFFER
‘RRRR11 ‘RRRR10
]
Note:
If M = 1 and W/R = 1, set MEM_WR mode.
.
Note: 8 pages @
64 bytes pre page =
512 bytes total
Rows 0 to 15, R[3:0]
M
1 = Write
0 = Read
0x0C
Previous result,
Read-only
Write to CRCT triggers
MEM_WR or BUF_CRC action.
350 µs
TRSPS max
A[6:0]
CRCH
(previous HDQ)
Current
HDQ CRC
0x05
D[7]
...
D[0]
A[6]
...
W/R
A[0]
230 µs
Break pulse
TB+TBR min
CRC-8
logic
‘RRRR01 ‘RRRR00
0
0x03
0x02
0x01
0x00
1
0x07
0x06
0x05
0x04
2
0x0B
0x0A
0x09
0x08
0X34
...
...
...
...
...
...
...
...
...
...
D
0X37
0X36
0X35
E
0X3B
0X3A
0X39
0X38
F
0X3F
0X3E
0X3D
0X3C
Pages
0–7,
P[2:0]
128 x 32-bit EEPROM
Figure 8. Register and EEPROM Access Scheme
8
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Access to device control and data registers use the “Un-Mapped” address space with the “M” (Map bit) set to ‘0’.
Access to the EEPROM space uses a Memory Mapped scheme with the “M” bit set to ‘1’. Refer to Figure 9 for
details.
Memory Mapped Registers
R[3:0]
C[1:0]
W/R
1
R3
R2
R1
R0
C1
C0
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 7
Bit 6
Bits 5:2
Bits 1:0
= W/R: Read/Write command (1 = Write, 0 = Read)
= Map Bit, M = 1
= Row index: R[3:0]
= Column/Buffer index: C[1:0]
Unmapped Registers
A[5:0]
W/R
Bit 7
0
A5
A4
A3
A2
A1
A0
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 7 = W/R: Read/Write command (1 = Write, 0 = Read)
Bits 6:5 = Map Bit, M = 0
Bits 4:0 = HDQ register: A[5:0] Range = 0x00 to 0x3F
Figure 9. HDQ Command Byte Decode
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7 HDQ Access Method
HDQ Command Format
Bit #
W/R
M =0
M =1
7
6
POR
A[5:0]
R[3:0]
5
4
3
C[1:0]
2
0
1
(Wait for)
HDQ command
Read: 0
Map: 0
Command
M bit?
Write: 1
Command
W/R bit?
Map: 1
Map: 0
Yes
Clear
MEM_WR bit,
Save R[3:0]
Set HDQ data =
BUFFER[C]
No
Yes
No
Set
MEM_WR bit,
Save R[3:0]
Is MEM_W
bit set?
Set Register A[5:0]
= HDQ data
Is
PageEn[Page]
= 1?
Yes
Set Status:
CRCB_ERR bit
Yes
Set BUFFER[C]
= HDQ data
No
Set Status:
PGEN_ERR bit
Yes
Set CRCR =
CRC(BUFFER[C])
No
Map: 1
Prefetch
EEPROM[P:R]
to BUFFER
Yes
Is CRCT =
CRCR?
Set CRCR = 0xFF
Is A[5:0] =
BUFFER
Is A[5:0] =
CRCT?
Command
M bit?
Set CRCT
= HDQ data
Fetch
EEPROM[P:R]
to BUFFER
Set HDQ data =
Register A[5:0]
Receive HDQ
data from host
Is CRCT =
CRCR?
No
Set Status:
CRCB_ERR bit
Set CRCR = 0XFF
Yes
Return HDQ
Data to host
Is MEM_WR
bit set?
No
Is A[5:0] =
BUFFER?
No
Copy BUFFER
to EEPROM[P:R]
Yes
Set CRCR =
CRC(BUFFER[C])
Read back
EEPROM[P:R]
Yes
Is BUFFER =
EEPROM?
No
Set Status:
MEM_ERR bit
Clear MR_WR bit
Figure 10. HDQ Access Flow Chart
10
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EEPROM Access
The bq2028 provides 512 bytes of EEPROM non-volatile memory storage organized as 128 words x 32 bits. Due
to the address limitations of the HDQ interface protocol, the EEPROM is accessed in 8 pages, with 16 rows of 4
bytes each. For IC manufacturing and analog trim data, 16 bytes or 4 words are reserved in last page of data.
The access model terminology is listed below:
EEPROM
=
128x32-bit (512 bytes) non-volatile memory with paged access
BUFFER
=
32-bit long word in 4x8b volatile Buffer
C
=
2-bit byte Column index for Buffer: C[1:0]
Buffer[C]
=
8-bit access to BUFFER at index C. MSB is at byte indexed by C='11‘.
P
=
3-bit Page index for EEPROM: P[2:0] (8 pages/EEPROM)
PAGE[P]
=
16x32-bit rows (64 bytes) from EEPROM indexed by [P]
R
=
4-bit Row index for EEPROM: R[3:0] (16 rows/page)
ROW[P,R]
=
32-bit long word from EEPROM indexed by [P,R]
Pre-Fetch
=
Automatic copy of an ROW[P,R] to BUFFER before read/write operation
M
=
Mapping operations to access BUFFER and EEPROM: M[1:0]
Buffer3
Buffer2
Buffer1
Buffer0
Page_Reg
BUFFER
Rows 0 to 15, R[3:0]
P[2:0]
Pages
0–7,
P[2:0]
128 x 32-bit EEPROM
Figure 11. Memory Map
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HDQ Registers
A summary of the Un-Mapped HDQ Registers is provided by Table 2.
Table 2. HDQ Un-Mapped Register Summary (1) (2)
A[5:0]
R/W
Register
B
A[5:0]
R/W
Register
B
A[5:0]
R/W
Register
B
A[5:0]
R/W
Register
0x00
R/W
Buffer0
–
0x10
–
(Reserved)
–
0x20
R
CRCR
–
0x30
R/W
(Reserved)
0x01
R/W
Buffer1
–
0x11
–
(Reserved)
–
0x21
R/W
CRCT
–
0x31
R/W
PageEn
0x02
R/W
Buffer2
–
0x12
–
(Reserved)
–
0x22
–
(spare)
–
0x32
R/W
(Trim)
0x03
R/W
Buffer3
–
0x13
–
(Reserved)
–
0x23
–
(spare)
–
0x33
R/W
(Trim)
0x04
R
Status
–
0x14
–
(Reserved)
–
0x24
–
(Reserved)
–
0x34
R/W
(Trim)
0x05
R/W
Control
–
0x15
–
(Reserved)
–
0x25
–
(Reserved)
–
0x35
R/W
(Trim)
0x06
-
(spare)
–
0x16
–
(Reserved)
–
0x26
–
(Reserved)
–
0x36
R/W
(Trim)
0x07
R/W
Page
–
0x17
–
(Reserved)
–
0x27
–
(Reserved)
–
0x37
–
(Reserved)
0x08
R/W
ADCTL1
–
0x18
–
(spare)
–
0x28
–
(Reserved)
–
0x38
–
(Reserved)
0x09
R/W
ADCTL2
–
0x19
–
(spare)
–
0x29
–
(spare)
–
0x39
–
(Reserved)
0x0A
R
ADHI
–
0x1A
–
(spare)
–
0x2A
–
(spare)
–
0x3A
–
(Reserved)
0x0B
R
ADLOW
–
0x1B
–
(spare)
–
0x2B
–
(spare)
–
0x3B
–
(Reserved)
0x0C
R
CRCH
–
0x1C
–
(spare)
–
0x2C
–
(Reserved)
–
0x3C
–
(Reserved)
0x0D
R
Row
–
0x1D
–
(spare)
–
0x2D
–
(Reserved)
–
0x3D
–
(Reserved)
0x0E
R
DeviceRev
–
0x1E
–
(spare)
–
0x2E
–
(spare)
–
0x3E
–
(Reserved)
0x0F
R
DeviceID
–
0x1F
–
(spare)
–
0x2F
–
(spare)
–
0x3F
–
(Reserved)
(1)
(2)
B = Defaults "Backed Up" in EEPROM Page[0] and auto-loaded at Power On Reset
Page[0] EEPROM Addresses 0x38 to 0x3F contain the TI Die ID but these are not mapped to HDQ registers.
32-bit BUFFER Access (addresses 0x00 through 0x03)
Access to the 32-bit words in the EEPROM is provided by a 32-bit BUFFER that is available as 8-bit HDQ
registers: Buffer0 [LSB], Buffer1, Buffer2, Buffer[MSB].
32-BIT BUFFER
MS-Byte
Buffer3
Name
Name
Name
Name
Access
Reset
7(MSB)
6
R/W
R/W
LS-Byte
Buffer2
Buffer1
Buffer0
5
4
3
2
Buffer0[7:0] (address 0x00) – Least Significant Byte
Buffer1[7:0] (address 0x01)
Buffer2[7:0] (address 0x02)
Buffer3[7:0] (address 0x03) – Most Significant Byte
R/W
R/W
R/W
R/W
Undefined
1
0
R/W
R/W
1
MEM_ERR
R
0
0
CRCB_ERR
R
0
Status Register (address 0x04):
Name
Access
Reset
7(MSB)
BUSY
R
0
6
ADC_DRDY
R
0
5
PGEN_ERR
R
0
4
MEM_WR
R
0
3
RSVD
R
0
2
RSTBIT
R
0
BUSY (bit 7): Busy flag. This bit is normally ‘0’ and is set to ‘1’ when the device is performing an extended
duration function such as device initialization, an ADC measurement or EEPROM write. Upon completion of
the function, the BUSY bit will automatically clear to ‘0’.
ADC_DRDY (bit 6): ADC Data ready flag. This bit indicates that conversion data is ready in the ADC Data
Registers (ADHI and ADLOW). This bit is cleared by setting the CONV bit in the Control register.
12
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1 – ADC data is ready
0 – ADC data is not ready.
PGEN_ERR (bit 5): Page Enable Error flag. This indicates that an EEPROM write was attempted to a page
that was not enabled for write-access.
MEM_WR (bit 4): Memory Write flag. This bit is set during the EEPROM memory access scheme when the
Map bit is set with an HDQ write command. This bit is cleared if the Map bit is set with an HDQ read
command or upon completion of an EEPROM program cycle. Refer to Figure 10.
RSTBIT (bit 2): This bit is set to ‘1’ when the device has reset due to a Power On Reset (POR) event or a
soft reset initiated by the Control:Reset bit. The RSTBIT will remain set to ‘1’ until the Control:RSTCLR bit is
set to ‘1’.
MEM_ERR (bit 1): This bit is set to ‘1’ when the device detects an EEPROM memory error. Refer to
Figure 10. This bit, along with CRCB_ERR, is cleared using the Control:ERRCLR bit.
CRCB_ERR (bit 0): This bit is set to ‘1’ when the device detects a BUFFER memory error after computing a
CRC check. Refer to Figure 10. This bit, along with MEM_ERR, is cleared using the Control:ERRCLR bit.
Control Register (address 0x05):
Name
Access
Reset
7(MSB)
CONV
R/W
0
6
RSVD
R
0
5
RSVD
R
0
4
ERRCLR
R/W
0
3
SLEEP
R/W
0
2
RSTCLR
R/W
0
1
RESET
R/W
0
0
SHUTDOWN
R/W
0
CONV (bit 7): Convert command bit. This bit is used to start an ADC conversion when set to ‘1’ and is
automatically cleared at the end of data conversion cycle in order to minimize HDQ traffic. At the start of
data conversion, the device sets the Status:BUSY flag and automatically clears the Status:ADC_DRDY flag
to indicate data conversion is in progress. When data conversion is complete, both the CONV bit and BUSY
flag are cleared and the ADC_DRDY flag is set. To abort an ADC conversion in process, the host can clear
the CONV bit to ‘0’.
ERRCLR (bit 4): A ‘1’ written to this bit will clear both the Status:MEM_ERR and CRCB_ERR bits. This bit
auto-clears itself so a readback always reads ‘0’.
SLEEP (bit 3): A ‘1’ written to this bit enables a lower-power mode with the HFO disabled. This bit is
automatically cleared upon detection of HDQ communication activity. Therefore a readback of this bit over
HDQ will always be ‘0’.
Note: If SLEEP mode is commanded, the host should wake up the bq2028 by issuing an HDQ break pulse
with no associated data, followed by a wait period of at least 200 us (tSLWU), then send a second HDQ
break pulse with the first command.
RSTCLR (bit 2): A ‘1’ written to this bit will clear the Status:RSTBIT flag and auto-clear itself so a readback
always reads ‘0’.
RESET (bit 1): A ‘1’ written to this bit will initiate a full device initialization. The device will auto-clear the
RESET bit and set the Status:RSTBIT and Status:BUSY flags at the start of initialization. After initialization
is complete the device will clear the BUSY flag.
SHUTDOWN (bit 0): A ‘1’ written to this bit will initiate a full device Shutdown. This bit is automatically
cleared upon a POR and must be cleared for correct HDQ activity. Therefore a readback of this bit over
HDQ will always be ‘0’.
Note: If SHUTDOWN mode is commanded, the host should wake up the bq2028 by issuing an HDQ break
pulse with no associated data, followed by a wait period of at least 15ms (tSHWU), then send a second HDQ
break pulse with the first command.
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Page Register (address 0x07): EEPROM Page Register
7(MSB)
RSVD
R
0
Name
Access
Reset
6
RSVD
R
0
5
RSVD
R
0
4
RSVD
R
0
3
RSVD
R
0
2
R/W
0
1
Page[2:0]
R/W
0
0
R/W
0
1
CHAN[1]
R/W
0
0
CHAN[0]
R/W
0
Page[2:0]: This contains the current 3-bit Page pointer for EEPROM access.
ADCTL1 (address 0x08): ADC Control Register 1
Final Product
Access
Reset
7(MSB)
RSVD
R/W
0
6
VRVDD
R/W
0
5
SPEED[1]
R/W
0
4
SPEED[0]
R/W
0
3
RSVD
R/W
0
2
CHAN[2]
R/W
0
RSVD (bit 7) Do not use.
VRVDD (bit 6): Voltage reference selection bit. This bit selects which voltage reference (either VDD or
internal VREF) is used by the ADC.
1 – Selects VDD as the ADC reference voltage for ratio metric conversions
0 – Selects the internal VREF as the ADC reference voltage
SPEED[1:0] (bits 5-4):
Conversion speed selection bits.
SPEED[1:0]
FILTER LENGTH
CONVERSION TIME
00
8192
125ms
01
4096
62.5ms
10
2048
31.25ms
11
512
7.8125ms
RSVD (bit 3) Do not use.
CHAN[2:0] (bits 2–0): ADC Channel selection bits. Set to VTEMP (‘101’) to measure the internal die
temperature sensor or set to VSS (‘111’) for measuring ADC offset.
14
CHAN[2:0]
ADC INPUT CHANNEL
(Product Datasheet)
000
RSVD
001
RSVD
010
RSVD
011
RSVD
100
RSVD
101
VTEMP
110
RSVD
111
VSS
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ADCTL2 (address 0x09): ADC Control Register 2
Final Product
Access
Reset
7(MSB)
RSVD
R
0
6
RSVD
R
0
5
RSVD
R
0
4
RSVD
R
0
3
RSVD
R
0
2
RSVD
R
0
1
RSVD
R
0
0
RSVD
R
0
RSVD (bits 7:0): Do not use.
ADHI (address 0x0A): ADC High Byte Data Register
This register provides the high byte ADC conversion data in 2’s complement format. A full scale (max value) for
this register is 7FFFh. A zero scale (min value) for this register is 8000h.
7(MSB)
Name
Access
Reset
6
5
4
3
2
1
0
R
0
R
0
R
0
R
0
3
2
1
0
R
0
R
0
R
0
R
0
ADC[15:8]
R
1
R
0
R
0
R
0
ADC[15:8] (bits 7:0): ADC high byte conversion data.
ADLOW (address 0x0B): ADC Low Byte Data Register
7(MSB)
Name
Access
Reset
6
5
4
ADC[7:0]
R
1
R
0
R
0
R
0
ADC[7:0] (bits 7:0): ADC low byte conversion data.
CRCH Register (address 0x0C): HDQ CRC Register
The register contains the CRC-8 result of the previous HDQ command + data sequence and is useful for data
integrity checks for single HDQ packet transfers.
7(MSB)
Name
Access
Reset
6
5
4
3
2
1
0
R
0
R
0
R
0
R
0
CHRH[7:0]
R
0
R
0
R
0
R
0
CHCH[7:0]: CRC-8 data from the previous HDQ packet. Data is computed using the full 16-bit HDQ
package sequence included W/R bit, 7-bit command and 8-bit data.
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Row Register (address 0x0D): EEPROM Row Register
Name
Access
Reset
7(MSB)
RSVD
R
0
6
RSVD
R
0
5
RSVD
R
0
4
RSVD
R
0
3
2
1
0
R
0
R
0
Row[3:0]
R
0
R
0
Row[3:0]: This contains the current 4-bit Row pointer for a particular page. The value is automatically
updated by Mapped access to the EEPROM.
DeviceRev Register (address 0x0E): Device Revision Register
Name
Access
Reset
7(MSB)
6
5
R
R
R
4
3
DeviceRev[7:0]
R
R
DeviceRev[7:0]
2
1
0
R
R
R
DeviceRev[7:0]: The read-only register returns the hardware device revision value The initial revision is
0x01 and increments by 1 for each design revision.
DeviceID Register (address 0x0F): Device ID Register
7(MSB)
Name
Access
Reset
6
5
4
3
2
1
0
R
R
R
DeviceID[7:0]
R
R
R
R
R
DeviceID[7:0] = 0x28
DeviceRev[7:0]: This read-only register returns the unique device identification value which provides a
method for the host to distinguish the bq2028 from other HDQ devices. The DeviceID for the bq2028 =
0x28.
CRCR Register (address 0x20): BUFFER CRC Result Register
7(MSB)
Name
Access
Reset
6
5
4
3
2
1
0
R
R
R
R
CRCR[7:0]
R
R
R
R
Undefined
CRCR[7:0]: This register contains the last BUFFER CRC computation result.
CRCT Register (address 0x21): BUFFER CRC Target Register
7(MSB)
Name
Access
Reset
6
5
4
3
2
1
0
R/W
0
R/W
0
R/W
0
R/W
0
CRCT[7:0]
R/W
0
R/W
0
R/W
0
R/W
0
CRCT[7:0]: This register contains the CRC computation target for verifying the BUFFER contents prior to
writing the data to EEPROM. This method is used to prevent EEPROM data corruption due to interrupted
HDQ transfers or communication errors. An HDQ write to this register triggers the comparison of the CRC
previously calculated as BUFFER data is loaded from the HDQ interface. If the MEM_WR flag is set and
the CRCT target register matches the CRCR result register, the device will write the BUFFER to the
EEPROM using the current ROW and PAGE register values. Then a read-back of the EEPROM will be rechecked to confirm the integrity of the memory write. Refer to flow chart in Figure 10 for CRC initialization
and computations. An HDQ read of this register returns the previously written target value.
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CONTROL2 (address 0x25): CONTROL2 Register
Name
Access
Reset
7(MSB)
RSVD
R/W
0
6
RSVD
R/W
0
5
RSVD
R/W
0
4
RSVD
R/W
0
3
RSVD
R/W
0
2
RSVD
R/W
0
1
RSVD
R/W
0
0
MANWREN
R/W
0
RSVD (bits 7:1): Do not use.
MANWREN (Bit 0): A ‘1’ enables write access to the Page 0 Manufacturer’s area registers and associated
EEPROM locations 0x30 through 0x3F. Users of the bq2028 may only change the PageEn register (0x031)
without adversely changing manufacturing trim data.
PageEn Register (address 0x31): Page Enable Register
Name
Access
Reset
7(MSB)
6
5
4
R/W
R/W
R/W
3
PageEn[7:0]
R/W
R/W
EEPROM Page[0], Address 0x31
2
1
0
R/W
R/W
R/W
PageEn[X]: Each bit maps to the associated EEPROM page and enables write access. An attempt to write
to Page[X] with PageEn[X]=0 will cause the PGEN_ERR bit to be set in the Status Register. This register
has a hardware write protection feature. To write to this register, the MANWREN bit must be set in the
Control 2 Register. This register is automatically loaded at reset with data stored in the EEPROM memory
(page 0, byte address 0x31)
1 – Page[X] is writable
0 – Page[X] is read-only
CRC FUNCTIONS FOR DATA INTEGRITY
For data integrity checks, the bq2028 provides a CRC-8 computation block with the polynomial function of
(X8+X5+X4+ 1). The following Python code indicates the parallel computation method where the 8-bit variable ‘c’
is the new data for calculating the CRC and the 8-bit variable ‘prev’ is the previous result if calculating the CRC
on multiple data items. To start a new sequence, the ‘prev’ variable is initialized with the value 0xFF. Note: The
initialization value of 0xFF is new in spec version 1.5. Previous versions used an initialization value of 0x00.
spacer
c ^= prev
for I in range(8):
if (c & 0x80):
c = ((c << 1 & 0xff)) ^ 0x31
else:
c = (c << 1) & 0xff
return c
Refer to the table below for example data sequences and the expected CRC:
EXAMPLE DATA SEQUENCE
(Byte order left to right)
CRC
0x00
0xAC
0xAA
0x8B
0xFF
0x00
0x00 0xAA
0xA6
0xAA 0x55
0x1B
0xFF 0x01 0x55
0x7F
0x00 0x01 0x55 0xAA
0xF1
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The CRC-8 function is typically used for verification of EEPROM data integrity via the BUFFER. To prevent
EEPROM memory corruption, BUFFER data will not be written to EEPROM without passing a CRC verification
check. Refer to the Figure 10 flow-char for the HDQ Access Method related to CRC computation and verification.
The additional complexity of this CRC-8 computation method is provided to minimize HDQ overhead traffic when
performing data integrity checks on variable length data elements.
The CRC-8 function is initiated on every HDQ data transfer with the result of the previous CRC-8 stored in the
CRCH register. The CRCH register is typically used for single HDQ data packet integrity checks. Since the HDQ
protocol shifts data with the LSB arriving first, the CRC is computed in this order:
A0:A6, R/W, D0-D7.
Note: This is the opposite bit ordering from the BUFFER CRC-8 computations.
Memory Access HDQ host pseudo-code examples
8-bit EEPROM Write (Example is <Byte1>):
Crc8 = FnCRC8(Byte1)
// Pre-Compute CRC-8 for 8-bit data
WRITE ’1RRRR01’, Byte1
// Pre-fetch EEPROM ROW ‘RRRR’, Poke Buffer[1], Set MEM_WR
WRITE ’0100001’, Crc8
// Poke Crc8 to CRCT trigger MEM write and re-check
READ ’0000100’, Status
// Peek Status Register.
IF (Status && 0x03) THEN CALL bq2028_Error
// B0 = CRCB_ERR, B1 = MEM_ERR
spacer
8-bit EEPROM Read (Example is <Byte2>):
READ ’1RRRR10’, Byte2
// Fetch ROW ‘RRRR’ to BUFFER, Peek Buffer[2], Clear MEM_WR
Crc8 = FnCRC8(Byte2)
// Compute CRC-8 on 1 byte read
WRITE ’0100001’, Crc8
// Poke Crc8 to CRCT trigger MEM write and re-check
READ ’0000100’, Status
// Peek Status Register.
IF (Status && 0x03) THEN CALL bq2028_Error
// B0 = CRCB_ERR, B1 = MEM_ERR
spacer
16-bit EEPROM Write (Lower 2-Bytes)
Crc8 = FnCRC8(Byte0, Byte1)
// Pre-Compute CRC-8 for 16-bit data
WRITE ’1RRRR00’, Byte0
// Pre-fetch EEPROM ROW ‘RRRR’, Poke Buffer[0], Set MEM_WR
WRITE ’0000001’, Byte1
// Poke Buffer[1]
WRITE ’0100001’, Crc8
// Poke Crc8 to CRCT trigger MEM write and re-check
READ ’0000100’, Status
// Peek Status Register.
IF (Status && 0x03) THEN CALL bq2028_Error
// B0 = CRCB_ERR, B1 = MEM_ERR
spacer
16-bit EEPROM Read (Lower 2-Bytes)
READ ’1RRRR00’, Byte0
// Fetch ROW ‘RRRR’ to BUFFER, Peek Buffer[0], Clear MEM_WR
READ ’0000001’, Byte1
// Peek Buffer[1]
Crc8 = FnCRC8(Byte0, Byte1)
// Compute CRC-8 on 2 bytes read
WRITE ’0100001’, Crc8
// Poke Crc8 to CRCT trigger MEM write and re-check
READ ’0000100’, Status
// Peek Status Register.
IF (Status && 0x03) THEN CALL bq2028_Error
// B0 = CRCB_ERR, B1 = MEM_ERR
18
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24-bit EEPROM Write (Lower 3-Bytes)
Crc8 = FnCRC8(Byte0, Byte2, Byte3)
// Pre-Compute CRC-8 for 24-bit data
WRITE ’1RRRR00’, Byte0
// Pre-fetch EEPROM ROW ‘RRRR’, Poke Buffer[0], Set MEM_WR
WRITE ’0000001’, Byte1
// Poke Buffer[1]
WRITE ’0000010’, Byte2
// Poke Buffer[2]
WRITE ’0100001’, Crc8
// Poke Crc8 to CRCT trigger MEM write and re-check
READ ’0000100’, Status
// Peek Status Register.
IF (Status && 0x03) THEN CALL bq2028_Error
// B0 = CRCB_ERR, B1 = MEM_ERR
spacer
24-bit EEPROM Read (Lower 3-Bytes)
READ ’1RRRR00’, Byte0
// Fetch ROW ‘RRRR’ to BUFFER, Peek Buffer[0], Clear MEM_WR
READ ’0000001’, Byte1
// Peek Buffer[1]
READ ’0000010’, Byte2
// Peek Buffer[2]
Crc8 = FnCRC8(Byte0, Byte2, Byte3)
// Compute CRC-8 on 3 bytes read
WRITE ’0100001’, Crc8
// Poke Crc8 to CRCT trigger MEM write and re-check
READ ’0000100’, Status
// Peek Status Register.
IF (Status && 0x03) THEN CALL bq2028_Error
// B0 = CRCB_ERR, B1 = MEM_ERR
spacer
32-bit EEPROM Write (Full 4-Bytes)
Crc8 = FnCRC8(Byte0, Byte1, Byte2, Byte3)
// Pre-Compute CRC-8 for 32-bit data
WRITE ’1RRRR00’, Byte0
// Pre-fetch EEPROM ROW ‘RRRR’, Poke Buffer[0], Set MEM_WR
WRITE ’0000001’, Byte1
// Poke Buffer[1]
WRITE ’0000010’, Byte2
// Poke Buffer[2]
WRITE ’0000011’, Byte3
// Poke Buffer[3]
WRITE ’0100001’, Crc8
// Poke Crc8 to CRCT trigger MEM write and re-check
READ ’0000100’, Status
// Peek Status Register.
IF (Status && 0x03) THEN CALL bq2028_Error
// B0 = CRCB_ERR, B1 = MEM_ERR
spacer
32-bit EEPROM Read (Full 4-Bytes)
READ ’1RRRR00’, Byte0
// Fetch ROW ‘RRRR’ to BUFFER, Peek Buffer[0], Clear MEM_WR
READ ’0000001’, Byte1
// Peek Buffer[1]
READ ’0000010’, Byte2
// Peek Buffer[2]
READ ’0000011’, Byte3
// Peek Buffer[3]
Crc8 = FnCRC8(Byte0, Byte1, Byte2, Byte3)
// Compute CRC-8 on 3 bytes read
WRITE ’0100001’, Crc8
// Poke Crc8 to CRCT trigger MEM write and re-check
READ ’0000100’, Status
// Peek Status Register.
IF (Status && 0x03) THEN CALL bq2028_Error
// B0 = CRCB_ERR, B1 = MEM_ERR
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INTERNAL TEMPERATURE SENSOR
An internal die temperature sensor is available on the bq2028 to reduce the cost, power, and size of the external
components necessary to measure temperature. Temperature sensing uses the VBE method to present a voltage
to a delta-sigma ADC converter. The host reads the ADC data over the HDQ interface and uses firmware to
convert the data to Kelvin temperature units.
ADC data is formatted to 16-bits even though the data conversion performance may be limited to 10 effective
bits. An ADC conversion starts when the Control:CONV bit is set to ‘1’ and is automatically cleared at the end of
the data conversion cycle . At the start of data conversion, the device sets the Status:BUSY flag and
automatically clears the Status:ADC_DRDY flag to indicate data conversion is in progress. When data
conversion is complete, both the CONV bit and BUSY flag are cleared and the ADC_DRDY flag is set. To abort
an ADC conversion in process, the host can clear the CONV bit to ‘0’.
The data in the ADC Data Registers is stored in 2s complement format. Full scale (7FFFh) is referred to the
reference voltage (Vref), typically 1.225 V. A hardware protection circuit will not allow the converter to rollover
from a full scale value (7FFFh) to a min scale value (8000h).
CLOCK GENERATOR CIRCUITS
The clock generator circuits are used to generate the internal clocks for the bq2028. The primary internal clocks
are derived from the low frequency oscillator (32.768kHz), and the high frequency oscillator (8.389 MHz). The
analog oscillator circuits are trimmed for accuracy, and then divided down for use throughout the device in both
the analog and digital circuits. The bq2028 makes extensive use of clock gating to dynamically shutdown clocks
to modules and interfaces not in use for low power operation. The low frequency oscillator (LFO) is required to
run continuously during operation of the device with exception to a shutdown condition. The high frequency
oscillator (HFO) is dynamically enabled and disabled as needed.
Low Frequency Oscillator Operation
The 32.768 kHz low frequency oscillator clock is generated from a fully integrated oscillator circuit with no
requirements for external components. This circuit is trimmed for accuracy during factory production. The LFO
trim value is stored in EEPROM memory Page 0. The LFO trim value is automatically read from EEPROM and
written to the LFO trim register shortly after the device comes out of reset. The LFO output is divided down for
various interfaces and modules in the device, as shown in Table 3.
Table 3. LFO Clocked Interfaces
INTERFACE OR MODULE
REQUIRED WHEN:
Frequency
DIVIDE
HFO Trim Circuit
HFO is enabled
32.768 kHz
LFO
Reset Timer
Power up of device (4ms)
32.768 kHz
LFO
HDQ low timeout
HDQ line is pulled low for 2sec
128 Hz
LFO/256
High Frequency Oscillator Operation
The 8.389 MHz high frequency oscillator clock is generated from a fully integrated oscillator circuit with no
requirements for external components. The bq2028 trims the 8.389MHz high frequency clock output internally by
using an automatic high frequency trim circuit. Using the more accurate 32.768kHz clock as a reference, the high
frequency clock is adjusted until it is determined to be within the desired operating frequency. The trim circuit
continues to monitor and adjust the 8.389MHz clock as needed. Due to the nature of the trim algorithm, some
small changes may be noticed in the 8.389MHz clock as it is adjusted based upon operating conditions and the
32.768kHz reference clock. The HFO output is divided down for various modules in the device.
Table 4. HFO Clocked Interfaces
INTERFACE OR MODULE
REQUIRED WHEN:
FREQUENCY
DIVIDE
HFO Trim Circuit
HFO is enabled
8.389 MHz
HFO
HDQ Communication
HDQ interface is enabled
1.049 MHz
HFO/8
HDQ Register Access
Writing or reading unmapped HDQ registers
1.049 MHz
HFO/8
EEPROM Access
Reading or programming EEPROM memory
1.049 MHz
HFO/8
ADC
ADC conversion enabled
65.536 kHz
HFO/128
20
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Copyright © 2012, Texas Instruments Incorporated
Product Folder Links :bq2028
bq2028
www.ti.com
SLUSB22B – OCTOBER 2012 – REVISED NOVEMBER 2012
REVISION HISTORY
Changes from Original (October 2012) to Revision A
Page
•
Changed from "Typ." to "Typical" in Features bullet ............................................................................................................. 1
•
Deleted footnote "Assured by design. Not production tested" from DC Electrical Characteristics table. ............................. 4
•
Deleted footnote "Assured by design. Not production tested" from AC Electrical Characteristics table. ............................. 5
Changes from Revision A (October 2012) to Revision B
•
Page
Added Note 1 to ICC Supply Current ..................................................................................................................................... 4
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Copyright © 2012, Texas Instruments Incorporated
Product Folder Links :bq2028
21
PACKAGE OPTION ADDENDUM
www.ti.com
24-Jan-2013
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package Qty
Drawing
Eco Plan
Lead/Ball Finish
(2)
MSL Peak Temp
Op Temp (°C)
Top-Side Markings
(3)
(4)
BQ2028YZGR
ACTIVE
DSBGA
YZG
12
3000
Green (RoHS
& no Sb/Br)
SNAGCU
Level-1-260C-UNLIM
-40 to 85
BQ2028
BQ2028YZGT
ACTIVE
DSBGA
YZG
12
250
Green (RoHS
& no Sb/Br)
SNAGCU
Level-1-260C-UNLIM
-40 to 85
BQ2028
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight
in homogeneous material)
(3)
MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4)
Only one of markings shown within the brackets will appear on the physical device.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
Addendum-Page 1
Samples
PACKAGE MATERIALS INFORMATION
www.ti.com
4-Mar-2013
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
A0
Diameter Width (mm)
(mm) W1 (mm)
BQ2028YZGR
DSBGA
YZG
12
3000
180.0
8.4
BQ2028YZGT
DSBGA
YZG
12
250
180.0
8.4
Pack Materials-Page 1
B0
(mm)
K0
(mm)
P1
(mm)
W
Pin1
(mm) Quadrant
1.59
2.45
0.69
4.0
8.0
Q1
1.59
2.45
0.69
4.0
8.0
Q1
PACKAGE MATERIALS INFORMATION
www.ti.com
4-Mar-2013
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
BQ2028YZGR
DSBGA
YZG
12
3000
210.0
185.0
35.0
BQ2028YZGT
DSBGA
YZG
12
250
210.0
185.0
35.0
Pack Materials-Page 2
X: Max = 2.4 mm, Min = 2.3 mm
Y: Max = 1.54 mm, Min = 1.44 mm
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