English
Language : 

BQ20Z75_14 Datasheet, PDF (10/23 Pages) Texas Instruments – SBS 1.1-COMPLIANT GAS GAUGE AND PROTECTION-ENABLED IC
bq20z75
Not Recommended for New Designs
SLUS723C – JULY 2007 – REVISED JULY 2008
www.ti.com
SMBus Timing Characteristics (continued)
TA = –40°C to 85°C Typical Values at TA = 25°C and V(REG25) = 2.5 V (Unless Otherwise Noted)
PARAMETER
TEST CONDITIONS
MIN
t(TIMEOUT) Error signal/detect (see Figure 1)
See (1)
25
t(LOW)
Clock low period (see Figure 1)
4.7
t(HIGH)
Clock high period (see Figure 1)
See (2)
4.0
t(LOW:SEXT) Cumulative clock low slave extend time
See (3)
t(LOW:MEXT) Cumulative clock low master extend time (see
Figure 1)
See (4)
tf
Clock/data fall time
tr
Clock/data rise time
See (5)
See (6)
TYP MAX
35
50
25
10
300
1000
UNIT
µs
µs
µs
µs
µs
ns
ns
(1) The bq20z75 times out when any clock low exceeds t(TIMEOUT).
(2) t(HIGH), Max, is the minimum bus idle time. SMBC = SMBD = 1 for t > 50 ms causes reset of any transaction involving bq20z75 that is in
progress. This specification is valid when the NC_SMB control bit remains in the default cleared state (CLK[0]=0).
(3) t(LOW:SEXT) is the cumulative time a slave device is allowed to extend the clock cycles in one message from initial start to the stop.
(4) t(LOW:MEXT) is the cumulative time a master device is allowed to extend the clock cycles in one message from initial start to the stop.
(5) Rise time tr = VILMAX – 0.15) to (VIHMIN + 0.15)
(6) Fall time tf = 0.9VDD to (VILMAX – 0.15)
t(LOW)
tr
tf
t(HD:STA)
SCLK
SDATA
P
t(HD:STA)
t(HD:DAT)
t(HIGH)
t(SU:DAT)
t(SU:STA)
t(SU:STO)
t(BUF)
S
S
P
Start
t(LOW:SEXT)
SCLKACK(1)
t(LOW:MEXT)
t(LOW:MEXT)
Stop
SCLKACK(1)
t(LOW:MEXT)
SCLK
SDATA
(1) SCLKACK is the acknowledge-related clock pulse generated by the master.
Figure 1. SMBus Timing Diagram
10
Submit Documentation Feedback
Product Folder Link(s): bq20z75
Copyright © 2007–2008, Texas Instruments Incorporated