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SH3100 Datasheet, PDF (54/80 Pages) Semtech Corporation – Supervisory IC with I2C Interface and PWM
SH3100
POWER MANAGEMENT
Pad Specifications (continued)
I2C Communication: SCL & SDA
The I2C pads are designed to comply with the 400kHz (Fast) I2C specification. The pads are open drain outputs with
diode protection only to GND. This allows VDD to collapse without affecting the common bus. Input stages include
input hysteresis and glitch filtering to allow handling of noisy inputs. High levels and rise times are set by external
pull-up resistors on SCL and SDA.
Parameter
Maximum operating frequency
Vout Low (Iol = 3 mA, VDD > 2V)
Vout Low (Iol = 3 mA, VDD < 2V)
Vin High
Vin Low
Input hysteresis (VDD > 2 V)
Input hysteresis (VDD < 2 V)
Input glitch rejection
Input leakage
Input capacitance
Output fall time (Load Cb = 10 pF to 400 pF)
Symbol
FOP
VOL1
VOL2
VIH
VIL
VHYS1
VHYS2
TSP
IIN
CIN
TF
Min
1
0.7VDD
0.05VDD
0.1VDD
50
-10
20 + 0.1Cb
Max
0.4
0.2VDD
0.3VDD
100
10
10
300
Units
MHz
V
V
V
V
V
V
ns
μA
pF
ns
Multi-Function Output: PWM
Multi mode pad with function determine by operating mode selection. Includes diode protection to VDD and GND.
Mode 1 is a standard digital output powered from VDD. Used for general-purpose PWM drive, fan speed control, or
switching regulation using external switching transistors.
Mode 2 is for bootstrap boost regulation with internal switching. PWM is pulled Low to energize the inductor and then
set High Impedance to allow energy transfer to VDD through the protection diode. Mode 3 is the power output from
the LDO.
Parameter
Vout High (Mode 1, VDD > 3.3 V, Ioh = 4 mA)
Vout Low (Mode 1 or 2, VDD > 3.3 V, Iol = 4 mA)
Vout High (Mode 1, VDD > 1.7 V, Ioh = 1 mA)
Vout Low (Mode 1 or 2, VDD > 1.7 V, Iol = 1 mA)
Pad rise time (Mode 1, 10 pF load)
Pad fall time (Mode 1 or 2, 10 pF load)
LDO output voltage range (Mode 3)
Min
Voh1
Vol1
Voh2
Vol2
Tr
Tf
Vldo
Typ
VDD – 0.4
0
VDD – 0.25
0
3
Max
VDD
0.4
VDD
0.25
10
10
4.5
Units
V
V
V
V
ns
ns
V
© 2006 Semtech Corp.
54
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