DS4432: Fix integer overflow for vcore values of 4900 mv and higher

Signed-off-by: Robin van der Gracht <[email protected]>
skot · Jul 5, 2024 · 1c5fa83 · 1c5fa83
1 parent dd2f094
commit 1c5fa83
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Showing 2 changed files with 4 additions and 4 deletions.
diff --git a/main/DS4432U.c b/main/DS4432U.c
@@ -49,13 +49,13 @@ bool DS4432U_test(void)
 
 uint8_t DS4432U_voltage_to_reg(uint32_t vout_mv, uint32_t vnom_mv,
                                uint32_t ra_ohm, uint32_t rb_ohm,
-                               int32_t ifs_na, uint32_t vfb_mv)
+                               uint32_t ifs_na, uint32_t vfb_mv)
 {
     uint8_t reg;
     // Calculate current flowing though bottom resistor (Rb) in nA
-    int32_t irb_na = (vfb_mv * 1000 * 1000) / rb_ohm;
+    int32_t irb_na = ((uint64_t)vfb_mv * 1000 * 1000) / rb_ohm;
     // Calculate current required through top resistor (Ra) to achieve vout in nA
-    int32_t ira_na = ((vout_mv - vfb_mv) * 1000 * 1000) / ra_ohm;
+    int32_t ira_na = ((uint64_t)(vout_mv - vfb_mv) * 1000 * 1000) / ra_ohm;
     // Calculate the delta current the DAC needs to sink/source in nA
     uint32_t dac_na = abs(irb_na - ira_na);
     // Calculate required DAC steps to get dac_na (rounded)

diff --git a/main/DS4432U.h b/main/DS4432U.h
@@ -11,5 +11,5 @@ esp_err_t DS4432U_set_current_code(uint8_t output, uint8_t code);
 esp_err_t DS4432U_get_current_code(uint8_t output, uint8_t *code);
 uint8_t DS4432U_voltage_to_reg(uint32_t vout_mv, uint32_t vnom_mv,
                                uint32_t ra_ohm, uint32_t rb_ohm,
-                               int32_t ifs_na, uint32_t vfb_mv);
+                               uint32_t ifs_na, uint32_t vfb_mv);
 #endif /* DS4432U_H_ */