SX1509BIULTRT Semtech, SX1509BIULTRT Datasheet - Page 13

• Manufacturer Part Number: SX1509BIULTRT
• Description: 16-chan GPIO W/ LED Driver & Keypad Engine (I2C)
• Manufacturer: Semtech

ADVANCED COMMUNICATIONS & SENSING
4.3
4.4
4.4.1
The SX1507, SX1508 and SX1509 generate their own power on reset signal after a power supply is connected
to the VDDM pin. The reset signal is made available for the user at the pin NRESET. The rising edge of the
NRESET indicates that the startup sequence of the SX1507, SX1508 or SX1509 has finished. NRESET must be
connected to VDDM (or greater) either directly, or via a resistor.
Rev 1 – 30
1. Device behavior is undefined until VDDM rises above VPOR, at which point NRESET is driven to GND
2. After t
SX1509 16-channel I
Reset
by the SX1507, SX1508 or SX1509.
Hardware (NRESET)
pulled high by an external resistor.
th
NRESET
Oct. 2009
VDDM
RESET
NRESET
ADDR1
ADDR0
VDROPH
VDROPL
VDDM
Figure 6 – 16-channel Low Voltage GPIO with LED Driver and Keypad Engine
VPOR
SDA
Undefined
SCL
, NRESET is released (high-impedance) by the SX1507, SX1508 or SX1509 to allow it to be
1
2
C GPIO with LED Driver and Keypad Engine
t
Sleep/Wakeup
RESET
64 Keys Max
Figure 7 – Power-On / Brown-out Reset Conditions
Keypad
Engine
Reset
Input
Filter
Auto
2
3
t
PULSE
SX1509
Clock Mgmt
I
Control
Oscillator
External
4
OSCIO
2
Internal
GND
Clock
C Bus
13
5
8-Bit
R/W
8-Bit
R/W
Undefined
World’s Lowest Voltage Level Shifting GPIO
Intensity (PWM)
LED Driver
Breath (Ramp)
I/O Bank A
A
I/O Bank B
A
Blink (Timer)
Interrupt
with LED Driver and Keypad Engine
6
Undefined
SX1507/SX1508/SX1509
1
t
RESET
VCC1
I/O[0]
I/O[1]
VCC2
NINT
I/O[2]
I/O[3]
I/O[4]
I/O[5]
I/O[6]
I/O[7]
I/O[8]
I/O[9]
I/O[10]
I/O[11]
I/O[12]
I/O[13]
I/O[14]
I/O[15]
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