The simplified block diagram of a 10-bit A/D converter of dual slope integrator type is shown in figure. The 10-bit counter at the output is clocked by a 1 Mhz clock. Assuming negligible timing overhead for the control logic, the maximum frequency of the analog signal that can be converted using this A/D converted is approximately .

• A.  500 Hz.
• B.  2 KHz.
• C.   1 KHz.
• D.  250 Hz.

Answer: (C)