Specifications
DATA SHEET QF4A512
Rev D4, Dec 07 7 www.quickfiltertech.com
V
OH
High-level Output Voltage, DV
DD18
= 1.6V, I
OH
= -100uA 1.4 V
V
OL
Low-level Output Voltage, DV
DD18
= 3.0V, I
OL
= 100uA 0.2 V
C
O
Output Capacitance 10 pF
C
L
Load Capacitance 20 pF
1. System calibration will reduce these errors to below the noise level.
2. System calibration at any temperature will eliminate this error.
3. Programmable Gain Amplifier set at a gain of x1, f
IN
= f
s
/ 25
4. Input resistance may vary as much as +/-26% without calibration. See gain and offset calibration.
5. Standby is with all channels inactive, and analog front end turned off. Power down is when the oscillator/PLL is turned off.
†
The digital input and output pins are 5V-tolerant. Inputs may be driven with 5V signals, outputs can be connected via pull-ups to 5V levels.
1.5 Timing Requirements
Parameter Min Max Units Note
Input Clock Frequency, f
0
5 200 MHz
Serial Port Clock Frequency, f
SCLK
(Run and Configure Modes) 40 MHz
Serial Port Clock Frequency, f
EE
(EEPROM Mode) 5 MHz
PLL Clock Frequency, PLL_CLK 20 200 MHz
Chip select low pulse width 2/SYS_CLK ns
SYS_CLK frequency (User filters, sampling rates)
(((N
TAPS
+ 1)/2)+1)*f
S
PLL_CLK 6, 9
SYS_CLK frequency (Fixed G and H filters)
103* f
S
PLL_CLK 7, 9
SYS_CLK frequency (relative to SCLK) - 16-bit output
- 24-bit output
3*SCLK/16
SCLK/(8*N)
PLL_CLK 8, 9
Setup time, Chip Select (/CS) low to SCLK↑
5 ns
Setup time, SDI before SCLK↑
5 ns
Hold time, SDI after SCLK↑
5 ns
6. f
S
is the sampling rate for any given channel and N
TAPS
is the number of taps used in the associated
FIR. The highest value of the expression for any active channel defines the minimum frequency for
SYS_CLK.
7. This parameter is derived in similar fashion to the previous one and is determined by the fixed number
of taps used in the G and H filters.
8. This limit is caused by the requirement for DRDY to be cleared before /CS returns to a high level after
a data transfer. Two SYS_CLKS are required to clear DRDY this must occur before the data transfer is
completed. N is the number of channels active in the output data.
9. All three of the minimum conditions must be satisfied for correct device operation.