- Silicon Laboratories, Inc. Radio User Manual

Si4734/35-B20
Rev. 1.0 7
Table 5. 2-Wire Control Interface Characteristics
1,2,3
(V
DD
= 2.7 to 5.5 V, V
IO
= 1.5 to 3.6 V, T
A
= –20 to 85 °C)
Parameter Symbol Test Condition Min Typ Max Unit
SCLK Frequency f
SCL
0—400kHz
SCLK Low Time t
LOW
1.3 — — µs
SCLK High Time t
HIGH
0.6 — — µs
SCLK Input to SDIO
↓ Setup
(START)
t
SU:STA
0.6 — — µs
SCLK Input to SDIO
↓ Hold (START) t
HD:STA
0.6 — — µs
SDIO Input to SCLK
↑ Setup t
SU:DAT
100 — — ns
SDIO Input to SCLK
↓ Hold
4,5
t
HD:DAT
0—900ns
SCLK input to SDIO
↑ Setup (STOP) t
SU:STO
0.6 — — µs
STOP to START Time t
BUF
1.3 — — µs
SDIO Output Fall Time t
f:OUT
—250ns
SDIO Input, SCLK Rise/Fall Time t
f:IN
t
r:IN
—300ns
SCLK, SDIO Capacitive Loading C
b
— — 50 pF
Input Filter Pulse Suppression t
SP
— — 50 ns
Notes:
1. When V
IO
= 0 V, SCLK and SDIO are low impedance.
2. When selecting 2-wire mode, the user must ensure that a 2-wire start condition (falling edge of SDIO while SCLK is high)
does not occur within 300 ns before the rising edge of RST
.
3. When selecting 2-wire mode, the user must ensure that SCLK is high during the rising edge of RST
, and stays high until
after the first start condition.
4. The Si4734/35 delays SDIO by a minimum of 300 ns from the V
IH
threshold of SCLK to comply with the minimum
t
HD:DAT
specification.
5. The maximum t
HD:DAT
has only to be met when f
SCL
= 400 kHz. At frequencies below 400 KHz, t
HD:DAT
may be violated
as long as all other timing parameters are met.
20 0.1
C
b
1pF
-----------
+
20 0.1
C
b
1pF
-----------
+