You have an integrator with a reset switch, when the switch is closed the output will be 0V When it opens you will get a linear ramp at a rate of \$ - { V1\over R_1.C_1 }{V/s}\$

Assuming 50% duty cycle is garanteed if you measure that on an average reading DC voltmeter and you'll see. \$-{ V1\over 4R_1.C_1.F_{SW} }{V}\$

You have an integrator with a reset switch, when the switch is closed the output will be 0V When it opens you will get a linear ramp at a rate of \$ - { V1\over R_1.C_1 }{V/s}\$

Assuming 50% duty cycle is garanteed if you measure that on an average reading DC voltmeter and you'll see. \$-{ V1\over 4R_1.C_1.F_{SW} }{V}\$

What op-amp - you want a slew rate significantly faster than the ramp and a gain-bandwidth well above the switching frequency output capability should include ground ans as far negative ( opposite of V1) as needed. input capability should include ground.

I would consider using a negative source for V1 and and a LM351 or similar with ground as the negative op-amp power, if the other numbers check out.