PCA9665_2 © NXP B.V. 2006. All rights reserved.
Product data sheet Rev. 02 — 7 December 2006 5 of 91
NXP Semiconductors PCA9665
Fm+ parallel bus to I2C-bus controller
6.2 Pin description
[1] HVQFNpackage die supply ground is connected to both the VSS pin and the exposed center pad. The VSS
pinmust be connected to supply ground for proper device operation. For enhanced thermal, electrical, and
board-level performance, the exposed pad needs to be soldered to the board using a corresponding
thermal pad on the board, and for proper heat conduction through the board thermal vias need to be
incorporated in the PCB in the thermal pad region.
Table 2. Pin description
Symbol Pin Type Description
DIP20,
SO20,
TSSOP20
HVQFN20
D0 1 18 I/O Data bus: Bidirectional 3-state data bus used to
transfercommands, data and status between the bus
controller and the CPU. D0 is the least significant bit.
D1 2 19 I/O
D2 3 20 I/O
D3 4 1 I/O
D4 5 2 I/O
D5 6 3 I/O
D6 7 4 I/O
D7 8 5 I/O
i.c. 9 6 - internally connected: must be left floating (pulled
LOW internally)
VSS 10 7[1] power Supply ground
WR 11 8 I Write strobe: When LOW and CE is also LOW, the
content of the data bus is loaded into the addressed
register.Data are latched on the rising edge of either
WR or CE.
RD 12 9 I Read strobe: When LOW and CE is also LOW,
causes the contents of the addressed register to be
presentedon the data bus. The read cycle begins on
the falling edge ofRD.
CE 13 10 I Chip Enable: Active LOW input signal. When LOW,
data transfers between the CPU and the bus
controller are enabled on D0to D7 as controlled by
theWR, RD and A0 to A1 inputs. When HIGH,
places the D0 toD7 lines in the 3-state condition.
Dataare wr itten into the addressed register on rising
edge of eitherCE or WR.
A0 14 11 I Address inputs: Selects the bus controller’s internal
registers and ports for read/write operations.
A1 15 12 I
INT 16 13 O Interrupt request: ActiveLOW, open-drain, output.
This pin requires a pull-up device.
RESET 17 14 I Reset: Active LOW input. A LOW level clears internal
registers and resets the I2C-bus state machine.
SCL 18 15 I/O I2C-bus serial clock input/output (open-drain).
This pin requires a pull-up device.
SDA 19 16 I/O I2C-busserialdata input/output (open-drain). This pin
requires a pull-up device.
VDD 20 17 power Power supply: 2.3V to 3.6 V