AT43USB325E-AU Atmel, AT43USB325E-AU Datasheet - Page 4

• Manufacturer Part Number: AT43USB325E-AU
• Description: IC USB KEYBOARD CTRLR 64LQFP
• Manufacturer: Atmel
• Series: AVR®r

Specifications of AT43USB325E-AU

• Applications: Keyboard Controller
• Core Processor: AVR
• Program Memory Type: SRAM (16 kB)
• Controller Series: AT43USB
• Ram Size: 512 x 8
• Interface: SPI, 3-Wire Serial
• Number Of I /o: 42
• Voltage - Supply: 4.4 V ~ 5.25 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 64-LQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

1.3
4
Name
V
CEXT1, 2
V
XTAL1
XTAL2
LFT
DPO
DMO
DP[2:5]
DM[2:5]
PA[0:7]
PB[0:7]
PC[0:7]
PD[0,1,3:7]
PE[0:3]
PE[4:7]
CC1, 2
SS1
,
2
Signal Description
AT43USB325
Type
Power Supply/Ground
Output
Power Supply/Ground
Input
Output
Input
Bi-directional
Bi-directional
Bi-directional
Bi-directional
Bi-directional
Bi-directional
Bi-directional
Bi-directional
Bi-directional
Bi-directional
Function
5V Power Supply
External Capacitors for Internal Voltage Regulator – A high quality 2.2µF capacitor must
be connected to CEXT1 and 0.33 µF to CEXT2 for proper operation of the chip.
Oscillator Input – Input to the inverting oscillator amplifier.
Oscillator Output – Output of the inverting oscillator amplifier.
PLL Filter – For proper operation of the PLL, this pin should be connected through a 0.01 µF
capacitor in parallel with a 100 resistor in series with a 0.1 µF capacitor to ground (VSS).
Both capacitors must be high quality ceramic.
Upstream Plus USB I/O – This pin should be connected to CEXT1 through an external
1.5 k pull-up resistor. DP0 and DM0 form the differential signal pin pairs connected to the
Host Controller or an upstream Hub.
Upstream Minus USB I/O
Port Plus USB I/O – Each of these pins should be connected to VSS through an external
15 k resistor. DP[2:5] and DM[2:5] are the differential signal pin pairs to connect
downstream USB devices.
Port Minus USB I/O – Each of these pins should be connected to VSS through an external
15 k resistor.
Port A[0:7] – Bi-directional 8-bit I/O port with controlled slew rate. These pins are used as
eight of the keyboard matrix column output strobes. PA[0:7] = COL[0:7].
Port B[0:7] – Bi-directional 8-bit I/O port controlled slew rate. These pins are used
as the eight of the keyboard matrix column output strobes: PB[0:7] = COL[8:15].
PB0 has a dual function: the input to timer/counter0.
Port C[0:7] – Bi-directional 8-bit I/O port with internal pull-ups. These pins are used as
keyboard matrix row input signals. PC[0:7] = ROW [0:7].
Port D[0,1,3:7] – Bi-directional I/O ports. Port D[1,4:7] have dual functions as shown below:
Port E[0:3] – Bi-directional I/O port with controlled slew rate which can be used as four
additional keyboard column output strobes, COL[16:19].
PE[4:7] – Bi-directional I/O port. PE[4:7] have built-in series limiting resistors and can be
used to drive LEDs directly
Ground
Port Pin
PB0
Port Pin
PD1
PD3
PD4
PD5
PD6
PD7
Alternate Function
T0, Timer/Counter0 external input
Alternate Function
T1, Timer/Counter1 External Input
INT1, External Interrupt Input 1
INTA, External Interrupt Input A
INTB, External Interrupt Input B
INTC, External Interrupt Input C
INTD, External Interrupt Input D
3355C–USB–4/05